applications for all sectors of industry and trade · logo! applications for all sec-tors of...

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Applications for all sectorsof industry and trade

August 2000

© Siemens AG 2000 LOGO! Application collectionAll rights reserved. August 2000

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Contents

LOGO! applications for all sec-tors of industry and trade

LOGO! is universally applicable. Withits high functionality and simple op-eration, LOGO! offers you a high de-gree of economy in almost every ap-plication and sector.

This collection of LOGO! applicationscontains information on practical ex-amples from industry and trade. Apartfrom the descriptions of the require-ments, you will find the comparisonbetween the previous solution and theLOGO! solution, the componentsused, the advantages and specialfeatures, and the corresponding con-trol program diagrams.

The individual functions to be com-bined are represented by easily un-derstood symbols in the LOGO! con-trol program. In practice, you simplylink these ready-made functions toyour control program, either directly atthe equipment or at the PC by meansof the convenient programming soft-ware LOGO!Soft Comfort.

LOGO!Soft Comfort provides you witha clearly arranged viewing area, onwhich you can display and modifyyour control program in the overallview. Free demonstration software andthe ready-made control programs canbe found quickly and conveniently onthe Internet or on a CD-ROM whichyou can request via your local LOGO!partner (see reverse).

Lighting control PageGuest rooms in luxury hotel 2Rows of luminaires 3Shop window lighting 5Exterior and interior lighting of a house 6Lighting in a sports hall 8Outdoor lighting 10

Monitoring systemsIntelligent door monitor systems 11First alarm 12Monitoring of parking lots 14

Door and gate controlGate control in a fire station 15Automatic door 16Industrial gate 18

Building installation examples under machine controlEconomical room automation 21Service water pump 22Watering of greenhouse plants 24Controlling roll-down shutters 25Bell system in a school 26

Heating, ventilation and air-conditioningLarge-scale refrigeration plants 27Ventilation system 28Continuous capacity utilization of three loads 30Boiler sequence control 32Ventilation control 34Step switch for ventilators 36Monitoring utilization time (solar energy system) 38

Transport systemsConveyor belt controller 41Controlling conveyor belts 42Control of an elevating platform 44Controlling strip heaters and conveyor belts 46

Machine controlReversible flow filters 49Control of a winder 50Controlling a bending machine 52Controlling a cream stirrer 53Sequence control of machines for welding cables 54Control of several pumps/pump pairs 55Cutting tool for fuses 58Changeover circuit (compressors) 60Intelligent pedal control 63Pump control 64Switching off and activation of pumps/fans 66Up/down movement with one momentary switch 68Sequence timer 70Cam timer 72Controlling a silo-filling system 74

Special solutionsWarning boards on french motorways 75Control of automatic feeders, for example for trout 76Killing Germs with Gas 78

LOGO! Application collection SiemensAugust 2000

2

Lighting controlLOGO! takes over Guest Rooms in Hongkong Luxury Hotel

The former “Hong Kong Renais-sance Hotel” is not only thebearer of a new name. Manyrooms of this establishmentknown today as the “Great Ea-gle Hotel” now featureLOGO! 24RL-a future-orientedcontrol system for enhancingthe comfort and convenience ofguests and technical personnel.

“Come in and feel at home", is themotto of the five star hotel in HongKong’s city. As soon as a guest opensthe door to the continually air-condi-tioned room, the light in the corridorautomatically turns on for half a min-ute. Ample time for switching on theadjacent main switch for lighting andtelevision. The energy relay, whichduring the guest’s absence takes careof temperature control and

ventilator regulation, switches offautomatically on activation of this mainswitch, allowing the hotel guest toadjust the temperature at will. The nextstep also does not require the guest tomove about, even though the roomand passageway lighting switches arelocated at three different points.

A visitor wishing just to rest simplypresses the “Do not disturb” switch,thereby causing LOGO! to disable theroom wake up alarm and door bell.Once the guest leaves the room afterrelaxation and activating the mainswitch, LOGO! switches the maincurrent supply completely off again-except that the passageway lightingstill stays on for thirty seconds and theenergy relay for automatic tempera-ture control is activated again.

Time to change

The new LOGO! room control facilitypays off of course not only for thehotel guest. With this logic module thehotel has acquired state of the arttechnology combined with cost sav-ings of almost two thirds. Unlike theprevious solution with its dedicatedelectronics, LOGO! is a standardproduct with open and user-friendlyprogramming: Considering the varietyof rooms, this greatly facilitates theindividual presettings for the technicalpersonnel.

No wonder therefore that LOGO! wonthe tender in competition with sevenother bidders. After the first fewmonths of operation, the “Great Eagle”was clearly convinced of the Siemensquality and LOGO!, and appreciatedthe technical support as well as thelocal supply service: The chief engi-neer of the hotel gave a credit ratingof 90 out of a 100 for LOGO! And thehotel has a further 400 rooms waitingto be fitted with this control system.

Modern times: LOGO! checks into hotelbuildings of the Hong Kong metropolis

Siemens LOGO! Application collectionAugust 2000

3

Lighting controlRows of luminaires

Requirements

In planning the lighting installations forcommercial rooms, the type and num-ber of luminaires are specified ac-cording to the desired illuminance.The fluorescent lamps are often ar-ranged in the form of rows of lumi-naires. Subdivision into individualcircuit groups takes place accordingto room utilization. The objective is toimplement control of the individualcircuit groups with LOGO!. It must bepossible to switch the individual rowsof luminaires directly and locally.When there is sufficient daylight, therows should be switched off automati-cally on the window side by a light-dependent switch. At 8 p.m. the lightsare switched off automatically, but itmust be possible to operate the light-ing manually at all times.

Previous solution

The luminaires are switched by cur-rent-pulse relays, operated by thepushbuttons at the door.

Independently of this, they are resetby the time switch or by the light-dependent switch, via the main-Offinput. The Off-commands must beshortened by interval time-delay re-lays, so that local operation is stillpossible after switching off.

LOGO! solution

The circuit can be considerably sim-plified with LOGO!. It is merely neces-sary to connect the pushbuttons andthe photoelectric switch to the inputterminals, and connect the luminairesto the output terminals. Contactorsshould be provided for higher powerswitching. The rows (Q1 to Q4) canbe switched on and off as required,via the pushbuttons at I1 to I4. If thephotoelectric switch at I5 responds,the rows at the window side (Q1 andQ2) are switched off. At 8 p.m. an Off-pulse is also generated via the integraltime switch, turning off all the rows.However, the lighting can still be op-erated manually.

Components used

- LOGO! 230RC

I1 pushbutton, luminaire 1(normally open)




I5 photoelectric switch(normally open)

Q1 luminaire 1, window sideQ2 luminaire 2, window sideQ3 luminaire 3, hall sideQ4 luminaire 4, hall side

Advantages and Specialties

Fewer components are required thanfor the conventional solution.Thanks to the reduced number ofswitching devices, a space-savingand smaller sub-distribution boardcan be used.The lighting installation can be easilymodified. For example, additionalswitching times can be set (se-quenced Off-pulses at the end of theday).

Previous solution

B1

L1

N

E1

E1

lx> K6

E5

K5

E4

K4

E3

K3

E2K3 K4 K5 K6

S1 S2 S3 S4

K1 K2

K2K2K1

B1

L1

N

E1

E1

lx> K6

E5

K5

E4

K4

E3

K3

E2K3 K4 K5 K6

S1 S2 S3 S4

K1 K2

K2K2K1


4

Lighting controlRows of luminaires (continued)

LOGO! wiring

Rows of luminaires controlled with LOGO!

L1 N I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

L1

NE2 E3 E4

B1

lx<

Row 1

E5

Row 2 Row 3 Row 4

S1 S2 S3 S4

LOGO! 230RC

A detailed description is includedin the LOGO! manual, chapter 7


5

Lighting controlShop Window Lighting

Requirements

A shop window display is to be auto-matically lit using LOGO!. There are 4different groups of lights. One forlighting during the day, one for addi-tional lighting in the evening, one forminimum lighting during the night andone for spotlights, to light particulararticles.

LOGO! Solution

The shop window is to be lit fromMonday to Friday from 8:00 in themorning until 10:00 in the evening, onSaturday from 8:00 to midnight and onSunday from midday until 8:00 in theevening. Within these times lightgroup 1 at Q1 is switched on via atime switch.

Additionally in the evening light group2 is switched on if the photo-sensitiveswitch at I1 responds. Outside of theabove-mentioned times, light group 3at Q3 takes over minimum lightingafter the photo-sensitive switch hasgiven the go-ahead. Via the motiondetector at I4 the spotlights areswitched on and off during the wholetime (light group 4 at Q4).Via the test switch at I3 all the lightgroups can be switched on for 1 min-ute, for example to test their functionor to set them up.

Components used

- LOGO! 230RI1 Photo-sensitive switch

(NO contact)I2 ON switch (NO contact)I3 Test switch (NO contact)I4 Motion detector (NO contact)

Q1 Light group 1Q2 Light group 2Q3 Light group 3 (minimum lighting)Q4 Light group 4 (spotlights)


The set time ranges can be changedat any time as desired.Other combinations of light groupscan easily be selected.Fewer components are necessarythan for conventional solutions.

Shop window lighting with LOGO!


6

Lighting controlExterior and Interior Lighting of a House

Requirements

The exterior and interior lighting of ahouse is controlled using LOGO!. Inthe absence of the occupants andwhen it is dark, persons approachingare to be detected and the exteriorand interior lighting switched on viamotion detectors and the alarm con-tact of an alarm system.

LOGO! Solution

The exterior lighting is divided intothree areas (at Q1, Q2, Q3). Eacharea has its own motion detector (atI2, I3, I4). If one of these motion de-tectors is activated during a certainperiod the corresponding exteriorlighting is switched on for 90 seconds.The time period is set via a time switchintegrated in LOGO! (5:00 in the eve-ning to 7:00 in the morning).

The photo-sensitive switch at I1 guar-antees that the lighting is onlyswitched on when it is dark. A fourthmotion detector is connected at I5,which independent of time and dark-ness switches on all exterior lightingfor 90 seconds. The exterior lighting isalso switched on via the alarm contactof the alarm system at I6 for 90 sec-onds.In addition, after switching off theexterior lighting, the interior lighting isswitched on for 90 seconds. Via themotion detector at I5 and the alarmcontact the internal lighting is immedi-ately switched on for 90 seconds.

Components used

I1 Photo-sensitive switch(NO contact)

I2 Motion detector 1 (NO contact)I3 Motion detector 2 (NO contact)I4 Motion detector 3 (NO contact)I5 Motion detector 4 (NO contact)I6 Alarm contact of the alarm system

(NO contact)

Q1 Exterior lighting 1Q2 Exterior lighting 2Q3 Exterior lighting 3Q4 Interior lighting


Energy savings due to the coupling oftime switch, photo-sensitive switchand motion detector.The set times can easily be changed;for example, other time ranges for thetime switch or other time periods forthe lighting.Fewer components used than forconventional solutions.

Exterior and interior lighting of a house with LOGO! (1)


7

Lighting controlExterior and Interior Lighting of a House (continued)

Exterior and interior lighting of a house with LOGO! (2)


8

Lighting controlLighting in a Sports Hall

Requirements

The lighting in the sports hall andchanging rooms of a school is con-trolled using LOGO!. As various sportsclubs have also rented the sports hallin the evenings, LOGO! has beenprogrammed to switch the lighting offat a set time so that the clubs cannotuse the hall for longer than permitted.Via a central switch, the lighting canbe switched on and off completelyindependently.

LOGO! Solution

The lighting in the sports hall (at Q1and Q2) can be switched on and offvia the button at I1. The lighting in thechanging rooms can be switched onand off via the button at I2.

The lighting is switched off in the eve-ning via the integrated time switch. At9:45 in the evening a horn sounds for5 seconds to warn that the time is up.There is time to leave the sports halland switch off the light. At 10 o’clockthe first light group in the sports hall(Q1) is switched off and at 10:15 thesecond light group (Q2). The lightingin the changing rooms is switched offat 10:25. The light cannot be switchedon again after that. Via a centralswitch, the lighting can be switchedon and off completely independently(for example, by the caretaker).The holiday periods can be manuallyexcluded via the locking switch at I4.Fewer components necessary than forconventional solutions.

Components used

- LOGO! 230RCI1 Sports hall lighting button

(NO contact)I2 Changing room lighting button

(NO contact)I3 Central switch (NO contact)I4 Locking switch for holidays

(NO contact)

Q1 Sports hall lighting group 1Q2 Sports hall lighting group 2Q3 Changing room lightsQ4 Horn


The system can easily be adapted forother times that the hall is in use.Fewer components necessary than forconventional solutions.

Lighting in a sports hall with LOGO! (1)


9

Lighting controlLighting in a Sports Hall (continued)

Lighting in a sports hall with LOGO! (2)


10

Lighting controlOutdoor Lighting

Requirements

The exterior lighting of a building is tobe controlled using LOGO!. There aretwo kinds of lighting: main and secon-dary lighting with manual or automaticoperation. The main lighting isswitched on for the whole of the settime, the secondary lighting only atcertain times when a motion detectoris activated. The lighting is generallyonly switched on when it is dark.

LOGO! Solution

The main lighting (at Q1) is only auto-matically switched on during the pe-riod from 6:00 in the morning to 12:00at night if the photo-sensitive switch atI1 also responds.

The secondary lighting (at Q2) isswitched on via the motion detector atI2 for 90 seconds (during the periodsfrom 6:00 to 8:00 in the morning andfrom 5:00 to 12:00 in the evening).Via I4 (manual setting) the main andsecondary lighting are switched onindependent of the time switch andphoto-sensitive switch; for example,for test purposes

Components used

- LOGO! 230RCI1 Photo-sensitive switch

(NO contact)I2 Motion detector (NO contact)I3 "Automatic" setting (NO contact)I4 "Manual" setting (NO contact)Q1 Main lightingQ2 Secondary lighting


Energy savings due to the coupling oftime switch, motion detector andphoto-sensitive switch.The times can be set individually; forexample, different times on workdaysand weekends or other time periods.The lighting system can easily beexpanded; for example, additionalmotion detectors or other lightinggroups to differentiate more clearlybetween the various areas.

Outdoor lighting, controlled by LOGO!


11

Monitoring systemsIntelligent Door Monitor Systems

Entry checks and security ap-proaches, usual for example inbanks, are implemented by theAtech company in France (Bor-deaux) with LOGO!

Atech, a company specializing inalarm systems and entry checks, isvery impressed by the connectionpossibilities and the integrated func-tions of LOGO!. Entry checks can nowbe combined quite easily with alarmsystems.

The counter function active at accesscontrol entrance and exit providesinformation at any time on whetherand how many persons are in thesupervised area. If, for example, thecounter state indicates at closing timethat too many persons remain on thepremises, an alarm is activated.

“Door opened” signal

Even at premises with security ap-proaches, the door monitor used byAtech is the LOGO! system. Simplesecurity approaches are frequentlyused in small branches of banks. Theyconsist of at least two doors whichenclose the bank forefront area. Assoon as the barrier of a door is deacti-vated, LOGO! blocks the other doorand permits only opening of “its” door.Simultaneously the “Door opened”status light is activated.In larger premises all LOGO! systemsare connected with each other via theAS interface, which also allows indica-tion statuses to the security center andthe control of different approaches bymeans of an OP7 operator panel. Forthis, the logic modules check theapproaches of two or three doors. TheLOGO! systems communicating witheach other allow the opening of onlyone portal at a prescribed time instant.

Easily installed, easily changed

The demand for more flexibility in suchapplications is fulfilled by LOGO!. Forif the lines to the sensors and actua-tors of the different approaches, por-tals, and the alarm center to theLOGO! switch cabinets are alreadyinstalled, Atech need only assign theintegrated functions to the differentsensors and to actuators. A modifica-tion for the access administration isdone simply through a change in theswitch program, without any need tohandle cabling lines once again.


12

Monitoring systemsFirst Alarm

Requirements

LOGO! is to be used on a machine orprocess where the occurrence of onealarm usually brings on severalalarms. The user then finds it difficultto see which alarm state came on firstand actually caused the problem. TheLOGO! is to be used to monitor thealarm states and indicate which alarmcame first.

LOGO! Solution

Inputs 1-4 are NO (NO-normally open,NC-normally closed) )alarm connec-tions. Inputs 5-7 are NC alarm con-nections. Input 8 is an additional NOcommon alarm from any other ‘FirstAlarm’ LOGO!s (if required). Outputs1-7 indicate which alarm came firstand Output 8 comes on when anyinput (including) I8 goes into an alarmstate.

When all inputs are in their normalstate and I9 (Reset) has been pressedand released, B07 output is high andall input AND gates are ‘active’. If anyalarm appears, the correspondinglatch is set. If any latch is set B07output is low, thus preventing anyother alarm registering.

If any alarm is set, Q8 also energisesto signal a general alarm state. As wellas providing indication, this outputcan be fed to the I8 input of additionalLOGO!s fitted with a similar ‘FirstAlarm’ program in order to preventany alarms on that LOGO! from reg-istering. Any number of alarm statescan then be monitored by using sev-eral LOGO!s each with their I8 and Q8connected to one common point.

Note:All alarms are retentive. This preventsthe loss of information about the firstalarm should a condition occur wherethere is a loss of control power. Theinformation about the first alarm is stillavailable when power is restored.

Components used

- e.g. LOGO! 24RCL (...0BA1)

I1 Alarm input 1 (NO Contact)I2 Alarm input 2 (NO Contact)I3 Alarm input 3 (NO Contact)I4 Alarm input 4 (NO Contact)I5 Alarm input 5 (NC Contact)I6 Alarm input 6 (NC Contact)I7 Alarm input 7 (NC Contact)I8 External Common Alarm input

(NO Contact)I9 Alarm Reset Push Button

Q1 Indicator alarm 1Q2 Indicator alarm 2Q3 Indicator alarm 3Q4 Indicator alarm 4Q5 Indicator alarm 5Q6 Indicator alarm 6Q7 Indicator alarm 7Q8 Indicator alarm 8


This system is very easy to use.It can be modified to suit any configu-ration.Several LOGO!s can be cascaded toalarm any number of alarm signals tobe monitored.Timers could be added to protectagainst false alarm indications.


13

Monitoring systemsFirst Alarm (continued)

First alarm detection with LOGO!


14

Monitoring systemsMonitoring of Parking Lots

Requirements

In a carpark there are a certain num-ber of parking lots available. The traf-fic lights at the entrance are to changeautomatically from green to red whenall the parking spaces are taken. Assoon as parking spaces become free,the lights change to green again toallow admittance to the carpark.

LOGO! Solution

Vehicles driving in and out of the car-park are counted via light barriers (atI1 and I2) with the counter integratedin LOGO!. When a vehicle enters thecarpark (I1) the counter adds 1 to thetotal and when a vehicle leaves thecarpark (I2) the counter subtracts 1from the total.

The counting direction (forwards/backwards) on the counter is definedvia I2 and the current impulse func-tion.When the set parameter has beenreached the traffic lights are switchedover at Q1.Via the button at I3 the count valueand output Q1 can be reset.

Components used

- LOGO! 230RI1 Light barrier "entrance"

(NO contact)I2 Light barrier "exit" (NO contact)I3 Reset button (NO contact)

Q1 Traffic light relay(changeover contact)


The current count value can be easilyindicated on the display.The maximum count value can bechanged as desired.The system can easily be expanded;for example, to close off the entrancewhen all the parking places are takenor to switch over between two countvalues (parking lots reserved for com-pany employees).

Monitoring of parking lots with LOGO!


15

Door and gate controlGate Control in a Fire Station optimized with LOGO!Bus andAS-Interface

In the course of the relocationand modernization of the controlcenter of the Bamberg volunteerfire brigade, remote control ofthe 24 vehicle hall folding doorshave been improved and opera-tions fully automated: By usinga centralized programmablelogic controller and LOGO!24RLB11 at the AS-interface.

In order to protect the city and itscitizens against fire, the Bambergvolunteer fire brigade station at theMargaretendamm is manned continu-ally around the clock with at least oneteam including two persons in the firebrigade control center. Twelve de-ployment vehicles are on standby forany emergency. Powered foldinggates at the front and rear of theparking areas can be remotely con-trolled from the control center, or lo-cally opened and closed from theactive vehicle using manual control.

Decentralized solution with ma-jor saving potential

The previous 88 relays in the switch-ing center as well as the contactorsand solonoids of the gate controls arereplaced by a central PLC, a SIMATICS7-300 with 315-2DP processor andLOGO! 24RLB11 logic modules fordecentralized gate controls. In placeof discrete wiring with 10 installationcables per gate, an AS interface busis used. PLC and logic modules ex-change control signals and statusmessages via this single two-wire line.

Action in the station

If an alarm is issued by the controlcenter, the PLC activates the alarmsignal and loudspeaker announce-ment. The lighting in the station andvehicle hall is switched on.

As soon as the compressed air supplyand charger holder of the vehicleshave been detached and the cableroller is activated, a switching pulse istransmitted to the gate control LOGO!.The hydraulic gate opening system isactivated. LOGO! sends the com-mands to the exhaust extraction sys-tem and switches on the exit trafficsignal light automatically. After depar-ture of the vehicles the gates areclosed and light and exhaust gas fanturned off again.

(Energy) saving program inclu-sive

The station manager and electricalengineer, Mr. Sehrig, who is responsi-ble for designing the system, consid-ers that the main benefits of theLOGO!Bus solution are the fewerneeds for switching units and cablesand the reduced installation expendi-ture. The system can be set up step-by-step under self-management. Theconvenient parameterization of thelogic modules allows testing and op-timization of different action variableswithout having to implement changesin the hardware. The controller canalso be subsequently adapted easilyto changing conditions. In future,lighting for the vehicle parking spacesand hall heating are to be optimizedfor energy economy using the LOGO!of the gate controller.

LOGO! controls 24 vehicle hall foldinggates of the Bamberg voluntary fire bri-gade


16

Door and gate controlControl of an Automatic Door

Requirements

Automatic door controllers are oftenencountered at the entrance doors ofsupermarkets, public buildings,banks, hospitals etc.The objective is to implement thecontrol of an automatic door withLOGO!. When someone approaches,the door must open automatically andremain opened until there is no longeranyone in the doorway region. Whenthat is the case, the door is to beclosed automatically after a shortdelay.

Previous solution

As soon as one of the two motiondetectors B1 or B2 senses a person,opening of the door is initiated via K3.When the detection area of the twomotion detectors is free for a minimumtime, K4 enables the closing opera-tion.

LOGO! solution

The circuit can be considerably sim-plified with LOGO!. It is merely neces-sary to connect the motion detectorsand limit switches to the input termi-nals, and connect the contactors tothe output terminals of LOGO!.The motion detectors at inputs I1 andI2 detect whether there is someone inthe doorway region. If one of the twomotion detectors responds, the door isopened via the contactor at output Q1.The minimum delay is implemented bymeans of the Off-delay integrated inLOGO!, until the door is closed again(via the contactor at output Q2).The final positions of the door aredetected by the limit switches at in-puts I3 and I4.

Components used

- LOGO! 230RC

I1 motion detector for exterior(normally open)

I2 motion detector for interior (nor-mally open)

I3 limit switch, door closed(normally closed)

I4 limit switch, door opened(normally closed)

Q1 contactor, open doorQ2 contactor, close door


Fewer components are required thanfor the conventional solution.The application can be very easilyextended to increase convenienceand ease of use.For example, an additional controlswitch can be connected for manualoperation (Open-Automatic-Closed).A seven-day timer can be used toprovide time and direction-dependentenabling of door opening.

Previous Solution LOGO! wiring

K 1 K 2

K 2 K 1

K 3 K 3

O p e n C lo s e

S 2 S 1

K 3

B 1 B 2 K 3

K 4

K 4

B 2

K 3

B 1

S 2

O p e n d o o r D e la y

A u x ilia r y c irc u it

L 1

N

L1 N I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

K1 K2

Open Close

B1 B2 S2S1

L1

N

LOGO! 230RC


17

Door and gate controlControl of an Automatic Door (continued)

Control of an automatic door with LOGO!


18

Door and gate controlControl of an Industrial Gate

Requirements

The driveway to company grounds isoften closed by a gate. This is onlyopened when vehicles are to accessor leave the grounds. The gate controlis operated by the gate keeper, whocan open and close the gate withpushbuttons. Normally, the gate isfully opened or closed. Travel can beinterrupted at any time. A flashing lightis switched on 5 seconds before thegate begins to travel and duringtravel. A safety lamp is used to ensurethat no one is injured and no objectsare trapped and damaged duringclosing of the gate..

LOGO! solution

As long as the opposite direction isnot switched on, travel of the gate isinitiated with start buttons Open at I1and Close at I2. Travel is terminatedwith the Stop button at I3 or by one ofthe limit switches (I4 for gate openand I5 for gate closed). Closing of thegate is also interrupted by the safetystrip at I6. The flashing light is con-nected to Q3.

Components used

- LOGO! 230RC

I1 Open button (normally open)I2 Close button (normally open)I3 Stop button (normally closed)I4 limit switch, gate open

(normally closed)I5 limit switch, gate closed

(normally closed)I6 safety pressure strip

(normally closed)

Q1 openQ2 closeQ3 flashing light


Fewer components are required thanfor the conventional solution. Thisallows a saving to be made in installa-tion time and space in the controlcabinet.

Previous solution LOGO! wiring

S 4S 3

K 1 K 5

K 3

S 1

O p e n C l o s e

S 0

K 3K 2

F l a s h i n g l i g h t

A u x i l i a r y c i r c u i t

L 1

N

K 1

H 1K 4

S 5 p >

K 6

K 6

K 1

S 2

S 2 K 3

K 2 K 4

O p e n C l o s e

K 5

S 5 p >

S 1

K 3 K 1

L1 N I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

K1 K2

Open Close

S4S3

L1

N

S1 S2 S0S5p>

S5 p>

Flashing light

H1

Open Close Stop

LOGO! 230RC


19

Door and gate controlControl of an Industrial Gate (continued)

Control of an industrial gate with LOGO!



20

Notes


21

Building installation examples under machine controlEconomical Room Automation with LOGO!

The Landis & Staefa companyhave a high opinion of LOGO!.The new hotel management sys-tem installed in the “RussischerHof” hotel in Weimar has finallyresulted in considerable savingscompared to alternative solu-tions - and therefore constitutesa considerable competitive ad-vantage. Landis & Staefa there-fore wish to use the HOTELGYR ®

and LOGO! combination in fur-ther building management pro-jects.

Since its reopening in 1999, the “Rus-sischer Hof” in Weimar has a newradiance. 125 modern hotel rooms -which leave nothing to be desired -await guests here. A HOTELGYR sys-tem solution of Landis & Staefa invisi-bly and discretely takes care of thecustomer during his or her entirestay. The personal keycard allows

access to all rooms and services. It isthe key for controlling electrical func-tions in one’s room, with the hotelsystem and LOGO! interacting opti-mally. Whereas the HOTELGYR roomcontroller communicates with thecentral computer of the hotel, carriesout access checking and regulatesthe climatic conditions of the room,LOGO! takes over control of all theswitches, electrical sockets and lampsin the room.

Enter!

The data of the keycard are trans-mitted by the card reader in the roomdoor to the room controller. On thebasis of the code it selects the appro-priate scenario and activates the cor-responding digital input of LOGO! Onarrival of a guest, for example, LOGOswitches on the corridor lamp withouta time limit. All other switches, socketsand lamps are enabled.

Simultaneously room temperaturecontrol is set to the “Comfort” operat-ing mode. If the system identifies aservice employee, all lamps areswitched on automatically and socketsand switches are enabled. Roomtemperature control remains in the“Economy" operating mode. On roomdeparture LOGO! again disconnectsall circuits for lighting and sockets.

Pushbuttons and plug-ins in-stead of wiring

The LOGO! 230RL logic module wassuccessful in this project against mi-cro PLCs and conventional switchingunits by virtue of its outstandingprice/performance ratio. Further im-portant decision criteria: The smalldimensions, the high switching ca-pacity of the relay outputs and highflexibility. A service technician canmake changes in the program on siteusing a laptop computer with softwareLOGO!Soft installed. A changedLOGO! program can be loadedthroughout the hotel by “plugging” aprogram module. Optional functionssuch as switching of a television set orcontrolling window blinds are simpleand can be quickly implemented.

State-of-the-art technology behind therenovated exterior: LOGO! in conjunctionwith a HOTELGYR system solution fromLandis & Staefa


22

Building installation examples under machine controlService Water Pump

Requirements

Rain water is increasingly being usedin addition to drinking water in resi-dential buildings. The following is apossible example for the use of rainwater. The rain water is collected in atank. It is pumped out of the tank by apumping system, into a piping instal-lation provided for the purpose. There,the rain water can be drawn off simi-larly to drinking water. If the tank be-comes empty, drinking water can besupplied. This means that servicewater must always be available. In anemergency, the control system mustautomatically select drinking water.During the changeover, rain watermust not reach the drinking watersupply. If there is insufficient water inthe rain water tank, the pump must notbe switched on (anti-dry-running pro-tection).

Previous solution

The pump and a solenoid valve arecontrolled via a pressure switch andthree float switches fitted in the rainwater tank. The pump must beswitched on when the pressure in thetank drops below a minimum value.When operating pressure is reached,the pump is switched off again after arun-on time of a few seconds. The run-on time prevents continual switchingon and off during a lengthy drawing-off of water.

Components used

- LOGO! 230RC

I1 pressure switch (normally open)I2 float switch (normally open)I3 float switch (normally closed)I4 float switch (normally closed)

Q1 pumpQ2 solenoid valve, drinking water

supply


Fewer components are required thanfor the conventional solution. Thisallows savings to be made in instal-lation time and space in the controlcabinet.Additional functions can also be inte-grated which, in a conventional sys-tem, would only be possible with ad-ditional equipment. For example, ena-bling of the pump at particular times,indication of an imminent or existingwater shortage, reporting of malfunc-tions.


K 1 K 2

K 3

P u m p D e l a yt i m e

S 1

K 3

S 4 K 3

R u n d r yp r o t e c t i o n

A u x i l i a r y c i r c u i tL 1

N

K 4

S 3 K 4

M a i n s w a t e ri n l e t

p <K 2

S 3 S 2

Y 1

L1 N I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

K1 Y1

Pump

S4S3

L1

N

S1 S2p<

Mains water inlet

LOGO! 230RC


23

Building installation examples under machine controlService Water Pump (continued)

Control of a service water pump with LOGO!



24

Building installation examples under machine controlWatering of Greenhouse Plants

Requirements

LOGO! is to be used to control thewatering of plants in a greenhouse.There are three different types ofplants. Type 1 are aquatic plants in apool whose water level must be keptwithin a certain range. The plants oftype 2 are to be watered each morn-ing and evening for 3 minutes and theplants of the third type every secondevening for 2 minutes.The automatic watering system can, ofcourse, also be switched off

LOGO! Solution

Watering of plant type 1:The water level in the pool is alwayskept in the set range via the floatswitches for maximum and minimumvalue (at I1 and I2).

Watering of plant type 2:Via the time switch the watering sys-tem is switched on for three minutes(daily) from 6:00 to 6:03 in the morningand from 8:00 to 8:03 in the evening.Watering of plant type 3:With the aid of the current impulsefunction the plants are watered onlyevery second day; always in the eve-ning for 2 minutes when the photo-sensitive switch at I3 responds.

Components used

- LOGO! 230RCI1 Float switch for maximum value

(NC contact)I2 Float switch for minimum value

(NO contact)

I3 Photo-sensitive switch(NO contact)

I4 Switch for automatically controlledwatering (NO contact)

Q1 Solenoid valve for watering planttype 1




The watering time can be changed inthe mornings and evenings as de-sired.In addition to watering the plants, thelighting or ventilation in the green-house can also be controlled byLOGO!.

Watering of greenhouse plants controlled by LOGO!


25

Building installation examples under machine controlControlling Roll-down Shutters

Requirements

LOGO! is to be used to control theshutters of a house. Manual operationor automatic control can be selectedvia a selector switch. Depending onthe time, darkness and day the shut-ters are either automatically rolled upor down.

LOGO! Solution

Manual operation:Via the switches at I2 (UP) and I3(DOWN) the shutters can be manuallyopened and closed, provided that theselector switch at I6 is not set atautomatic.

Automatic operation:For automatic operation the selectorswitch (I6) must be set at automatic. Ifthe photo-sensitive switch at I1 isactivated, the shutters are closed inthe period between 6:00 in the even-ing and 7:00 in the morning. They areopened during the day between 7:00in the morning and 6:00 in the even-ing.The position switches at I4 and I5determine whether the shutters areopen or closed.

Components used

- LOGO! 230RCI1 Photo-sensitive switch

(NO contact)I2 Manual switch UP (NO contact)I3 Manual switch DOWN

(NO contact)I4 Position switch 'shutters open'

(NC contact)

I5 Position switch 'shutters closed'(NC contact)

I6 Selector switch set at "automatic"

Q1 Open shuttersQ2 Close shutters


The times can easily be adjusted tothe individual circumstances; for ex-ample, different times on workdaysand at the weekend or during holi-days.Two areas/situations can be controlleddifferently via the outputs that are stillfree.Energy savings due to coupling oftime switch and photo-sensitiveswitch.

Controlling roll-down shutters with LOGO!


26

Building installation examples under machine controlBell System, e.g. in a School

Requirements

In a school the school bell is activatedby LOGO!. The bell is to ring at certaintimes for 2 seconds (school begin,breaks and end of school).

LOGO! Solution

Via the time switch integrated inLOGO! the times are set for the be-ginning of school, breaks and end ofschool.The bell is to ring on Mondays to Fri-days at 8:00, 9:45, 10:00, 12:45, 13:30and 16:30. On Friday school alreadyends, however, at 15:30. An ON delayguarantees that the bell only rings for2 seconds.

Components used

- LOGO! 230RQ1 Bell


Fewer components are necessarythan for conventional solutions.The bell system can easily be ex-panded; for example, switching thebell off during school holidays.

Control of a bell system with LOGO!; e.g. in a school

15:31h


27

Heating, ventilation and air-conditioningLOGO! controls large-scale Refrigeration Plants more eco-nomically

A small highly efficient supple-mentary controller has been in-stalled in department stores bythe Kopp engineering companyin Eckental near Nuremberg forlarge-scale refrigeration plants –with a single LOGO!

To keep customers cool while shop-ping, department stores are alwayspleasantly air-conditioned. For thispurpose, heating/ventilation and air-conditioning systems are commonlyinstalled in the top floor, which mustbe frequently switched on and off.With a decentralized controller thisrequires personnel having to go to theequipment frequently, costing bothtime and money. This is why operatorsare keen to increase the degree ofautomation. That was also the objec-tive for one of the more than sixty de-partment stores that engineer RainerKopp supervises. A large-scale refri-geration plant had to be controlled

from the central building control sys-tem using a supplementary controller.

In detail:

On workdays the refrigerating ma-chine has to be switched on automati-cally at a specific time before storeopening, in order to guarantee apleasant cool air temperature in ac-cordance with requirements. In theevening, it has to be switched off at anadjustable time (20 to 30 minutes)before the closing time programmedin the master system. Pumps andventilators should however continue torun for this exact period. In this way,the cold already produced is almostfully exploited and energy saved. Inaddition, for service work the systemmust be easily resettable to the origi-nal state.

Rainer Kopp has met these demandsusing only the six basic and eightspecial functions of a single LOGO!24R unit. The internal interlockingtimes as well as the time sequence ofthe individual switching steps arestored; it generates all necessarypulse signals and the required lagtime.

Two to three times as favorable

The LOGO! installed at the refrige-rating machine has proven itself asdecisively more economical than aconventional solution: “using normaltimers and other relays, for instance,the hardware would have cost aboutdouble and the wiring taken threetimes as long” estimates Rainer Kopp.He especially stresses the radicallysimplified storage and parts inventory:And as a man who travels a lot, RainerKopp values the flexibility of LOGO!With a couple of logic modules in hisluggage case and a notebook withLOGO!Soft he is equipped in the bestpossible way for many contingencies,and can also solve quickly and flexiblyproblems which only become evidenton site. Existing LOGO! controllerscan be changed or expanded, forexample, by simple reprogramming.


28

Heating, ventilation and air-conditioningControl of a Ventilation System

Requirements

A ventilation system is intended tosupply fresh air to a room, and extractthe used air. Each of the two fans ismonitored by an air flow monitor. At notime should the room become pres-surized. The fresh air fan may only beswitched on when safe operation ofthe exhaust air fan is signaled by theair flow monitor. An indicator light isintended to indicate failure of a fan.

Previous solution

The fans are monitored with air flowmonitors. When no air flow is meas-ured after a short delay has elapsed,the system is switched off and a fault

is reported; this can be acknowledgedby pressing the Off button.

LOGO! solution

Fan monitoring requires an evaluationcircuit and several switching devices,in addition to the air flow monitors. Theevaluation circuit can be replaced byone single LOGO!.The ventilation system can beswitched on via the pushbutton at I1,and off via the pushbutton at I2. If afault occurs, it is indicated via theindicator light at Q3, and the ventila-tion system is switched off.

Components used

- LOGO! 230RC

I1 Start button (normally open)I2 Stop button (normally closed)I3 Air flow monitor (normally open)I4 Air flow monitor (normally open)

Q1 exhaust air fanQ2 fresh air fanQ3 indicator light


Fewer components are required thanfor the conventional solution. Thisallows a saving to be made in installa-tion time and space in the controlcabinet.


K1 K5

K5

S1

Exhaust air Fresh air

S0

K3K2

Operation

Auxiliary circuitL1

N

S2

K1

v>

S2

H1K4

S3v>

K5

Fault

H2

K2 K4

L1N I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

K1 K2

Exhaustair fan

Fresh air fan

S1

L1

N

S2 S3v>v>

H1 H2

S0

LOGO! 230RC


29

Heating, ventilation and air-conditioningControl of a Ventilation System (continued)

Control of a ventilation system with LOGO!



30

Heating, ventilation and air-conditioningContinuous Capacity Utilization of Three Loads

Requirements

LOGO! has been used for switching agroup of three similar loads. Two ofthese three loads must always be inoperation at one time. To ensure equalwear on all three loads, they must bealternately switched on and off.Each load has an interrupt output,which is connected to a group inter-rupt. As soon as a load signals a fault,it is switched off and the other twoloads are in operation.

LOGO! Solution

The procedure for continuous capac-ity utilization of the loads is as follows.First of all, loads 1 and 2 (at Q1 andQ2) are in operation, then loads 2 and3 (at Q2 and Q3), then loads 1 and 3(at Q1 and Q3).

This procedure is continuously re-peated (beginning with Q1 and Q2).

The loads are in operation for the settimes (for example 3 seconds). Theprocedure is started via an invertedlatching relay. Also in the case ofvoltage recovery the system startsindependently (initial condition). If afault occurs with load 1 it is switchedoff via interrupt input I1 and the thirdload is switched in. The fault is indi-cated via the group interrupt at Q4.When the fault has been rectified andthe acknowledgment button at I4pressed, LOGO! returns to the initialcondition and the procedure startsagain beginning with Q1 and Q2. Thesame applies for loads 2 and 3 (errormessage of load 2 at I2, error mes-sage of load 3 at I3).

Components used

- e.g. LOGO! 230RI1 Interrupt input of load 1

(NO contact)

I2 Interrupt input of load 2(NO contact)

I3 Interrupt input of load 3(NO contact)

I4 Interrupt acknowledgment button(NO contact)

Q1 Load 1Q2 Load 2Q3 Load 3Q4 Group interrupt output


This solution can be used for anyloads.The operating times of the loads canbe changed as desired.The application can easily be ex-panded; for example, by a mainswitch for switching the loads on andoff.Fewer components are necessarythan for conventional solutions.

Continuous capacity utilization of three loads controlled by LOGO! (1)


31

Heating, ventilation and air-conditioningContinuous Capacity Utilization of Three Loads (continued)

Continuous capacity utilization of three loads controlled by LOGO! (2)


32

Heating, ventilation and air-conditioningBoiler Sequence Control

Requirements

LOGO! is to be used to ensure thatfour gas boilers do not start up simul-taneously. The start-up control for theboilers is enabled via a master ther-mostat.

LOGO! Solution

Each of the four boilers has two powersettings. Each power setting is as-signed to an output (Q1 to Q8). Themaster thermostat is connected to I1.The thermostat is used to set the tem-perature at which the boiler is to beswitched on and off. If the temperaturefalls below 70°C, the first power set-ting of boiler 1 (Q1) is activated forheating via I1.

Five minutes later, power setting 2 ofboiler 1 (Q2) is activated. Providedthat the final temperature has not beenreached, a further power setting (Q3to Q8) is enabled for reheating atintervals of 5 minutes. When the finaltemperature of 80°C is reached, theboilers are switched off in sequence.Starting with power setting 1 and 2 ofboiler 1, then after 5 minutes boiler 2,etc.

When the temperature falls, the boilersare activated again, starting with Q1.

Components used

- LOGO! 230RL

I1 Master thermostat

Q1 Power setting 1, boiler 1Q2 Power setting 2, boiler 11Q3 Power setting 1, boiler 2Q4 Power setting 2, boiler 2Q5 Power setting 1, boiler 3Q6 Power setting 2, boiler 3Q7 Power setting 1, boiler 4Q8 Power setting 2, boiler 4


The intervals can be adjusted in ac-cordance with performance and op-eration. Existing installations are easilymodified or adapted.Fewer components are required thanin the case of previous solutions.

Boiler sequence control with LOGO! (1)


33

Heating, ventilation and air-conditioningBoiler Sequence Control (continued)

Boiler sequence control with LOGO! (2)


34

Heating, ventilation and air-conditioningVentilation Control

Requirements

LOGO! has the task of controlling theheating and ventilation system in anoffice or shop. The control systemmust operate according to the time ofday and day of the week. There aretwo fans, one for fresh air and one forextracted air. Additionally, there mustbe a facility for the employees to ex-tend the operating time of the systemby two hours. Of course, the heatingmust also run when it becomes toocold in the office or shop. This is de-tected by an internal thermostat. Inaddition, various alarm messages areused.

LOGO! Solution

The fresh air fan at Q3 and the ex-tracted air fan/heating at Q4 operateduring working hours from 8:00 a.m. to6:00 p.m. (Monday through Friday)and from 8:00 a.m. to 1:00 p.m. onSaturdays. They are started via OR-block B05. They also run when thethermostat at I2 has responded orwhen the operating time has beenextended via the switch at I1. Theextended time is indicated by a signallamp at Q1. If the conditions for theoperating time of the fans are nolonger fulfilled, the extracted airfan/heating switches off and the freshair fan runs on for another 10 minutes.All fault messages are indicated viathe signal lamp at Q2. The followingfault messages are generated: I3 foroverrun, I4 for overheating, I5 and I6for clogged filters. All inputs except forI4 are combined with On-delays toprevent fault messages. The times canbe individually adjusted.

Components used

- e.g. LOGO! 230RC (...0BA0)

I1 Switch for extended time (nor-mally open)

I2 Thermostat (normally open)I3 Overrun (normally open)I4 Overheating (normally open)I5 Filter (normally open)I6 Filter (normally open)

Q1 Indicator for extended operatingtime

Q2 Indicator for fault messagesQ3 Fresh air fanQ4 Extracted air fan and heating


The cost of this solution is more than10% lower than that of the previouscontactor and time-delay relay solu-tion. In addition, it was possible toextend the application with some moretime-delay relays to rule out fault mes-sages, without increasing the costs.It was also possible to make savingsin the installation and workorder costs.


35

Heating, ventilation and air-conditioningVentilation Control (continued)

Ventilation control with LOGO!


36

Heating, ventilation and air-conditioningStep Switch, e.g. for Ventilators

Requirements

LOGO! is to be used for switchingbetween 4 speed levels of a ventilator.

LOGO! Solution

Via the button at I1 the ventilator isstarted at level 1. By pressing thebutton again the ventilator is switchedone level higher. This is possible up to4 times (Q1, Q2, Q3 and Q4).This 4-step switch has been madepossible by the integrated counter.Depending on how often button I1 waspressed, the corresponding contactoris released (I1 pressed twice ->Q2active). To make sure that only onecontactor is activated, switching be-

tween the individual contactors takesplace only after a short delay of 2seconds.With button I2 the ventilator can beswitched back step by step.

Components used

- e.g. LOGO! 230RI1 Button for up a level (NO contact)I2 Button for down a level

(NO contact)

Q1 Contactor level 1Q2 Contactor level 2Q3 Contactor level 3Q4 Contactor level 4


The number of levels of the stepswitch can be changed as desired (2,3 or 4 steps).The step switch can easily be ex-panded; for example, to switch off theventilator immediately if button I2 ispressed for a longer time.The delay before switching over caneasily be changed.Fewer components are necessarythan for previous solutions.

Step Switch with LOGO!, e.g. for Ventilators (1)


37

Heating, ventilation and air-conditioningStep Switch, e.g. for Ventilators (continued)

Step Switch with LOGO!, e.g. for Ventilators (2)


38

Heating, ventilation and air-conditioningMonitoring the Utilization Time, e.g. in a Solar Energy System

Requirements

LOGO! is to be used to ensure thatloads can only remain switched on fora specific length of time. If the presettime is exceeded, LOGO! switches theload off automatically. This is ex-tremely useful for solar energy sys-tems, because total battery drainagecan be prevented.

LOGO! Solution

LOGO! monitors the length of time forwhich the connected loads have beenswitched on. A different time can bespecified for each load.

An input is assigned to each output,i.e. if the switch on I1 is depressed,the load on Q1 is switched on imme-diately. The load can be switched onand off as often as necessary withinthe preset time interval, but when thisinterval is exceeded, LOGO! switchesthe load off automatically. The re-maining inputs and outputs are linkedtogether in the same manner (I2 withQ2; I3 with Q3).

The enable procedure is implementedas follows: The current switch-on du-ration is determined by the counterintegrated into LOGO! by means of apulse transmitter that supplies a pulseto the counter at one minute intervals.In this manner, the elapsed minutesare counted. The preset limit valuecorresponds to the maximum switch-on duration (e.g. 120 = 120 minutesfor Q1). When this count is reached,the load is switched off. The loadremains inhibited until an enable isreceived again from the time clock(e.g. every day at 6:00 hrs).

An additional LED connected to out-put Q4 indicates that the maximumswitch-on time will soon have elapsedby flashing 15 minutes before thepreset time is reached.

Components used

- LOGO! 12RCI1 Switch for load 1 (NO)I2 Switch for load 2 (NO)I3 Switch for load 3 (NO)

Q1 Load 1Q2 Load 2Q3 Load 3Q4 LED


Automatic load switch-off protects thebatteries from being totally drained.Fewer components are required thanfor a conventional solution.The switch-on durations can be easilymodified and adapted to new situa-tions.The enable time can be modified foreach load, e.g. only once a week.The time clock can also be used tolimit operation of the load to certaintimes.


39

Heating, ventilation and air-conditioningMonitoring the Utilization Time, e.g. in a Solar Energy System(continued)

Monitoring the Utilization Time, e.g. in a Solar Energy System with LOGO! (1)

Monitoring the Utilization Time, e.g. in a Solar Energy System with LOGO! (2)


40

Notes


41

Transport systemsConveyor Belt Controller with LOGO!Long

In the textile industry

Mark Marmer is boss of SignatureElectric Ltd., an electrical company inWillowdale (Ontario/Canada). Since hediscovered LOGO! at his electricalwholesaler and used it successfully ina textile impregnation plant, he alwaystakes the logic module along duringservice trips to customers. The reasonis that in Canada, too, time and moneycan be saved using the ready-madefunctions of the module.

Mark Marmer is an electrician takingcare of an impregnation plant, wheretextile bales are unrolled, drawn onconveyors through the impregnationbath and subsequently dried on hea-ted conveyor belts.

Impregnated and modernized

He now modernizes control of con-veyor and heater belts economicallywith a LOGO!Long instead of using 8time relays and one timer switch -cheaper by a third than with conven-tional technology.

The controller had to ensure that theconveyor belts of the system start upautomatically and slowly, to avoid anexcessive starting current. In additionthe customer required that the beltsare started and stopped in a coordina-ted manner. An application for LOGO!

The work of the logic module beginswith the automatic start of the systemand switching on of the ventilators.

15 minutes later LOGO! slowly startsthe four heater belts one after theother, at five minute intervals. Onlyafter 3 1/2 hours – the heating-upperiod for the heater belts takes thislong – does the controller start up inturn the three belts, time-delayed,where the textiles are drawn throughthe impregnating baths. After through-put of a day’s production, the heaterbelts of the system are turned off bypressing an off button. The ventilatorsreceive the switch-off signal fromLOGO! only after a delay time of afurther hour.

It has been no secret for a long timenow that LOGO! stands for operatingconvenience and cost savings.


42

Transport systemsControlling Conveyor Belts

Requirements

3 conveyor belts are to be controlledwith LOGO! to transport parts.The system connected to the con-veyor belts provides parts for theconveyor belt every 30 seconds. Eachpart needs about 1 minute to travelover the conveyor belt.As the system connected to the con-veyor belts can have a lot of deadtime, the belts must be automaticallystarted or stopped depending onwhether there are parts to be trans-ported or not.

LOGO! Solution

The system is switched on via the ONbutton at I2 and switched off via theOFF button at I1.The 3 conveyor belts are each drivenby a motor (at Q1, Q2, Q3), and 3proximity switches detect the part oneach conveyor belt (at I4, I5, I6).

Via a fourth proximity switch at I3, theparts at the beginning of conveyor belt1 are detected (parts coming from thesystem connected to the conveyorbelt).

When the ON button is pressed andthere are parts to be conveyed, theconveyor belts start up one after theother (in the order: belt 1, belt 2, belt3). If it takes more than 1 minute forthe next part to appear, the conveyorbelts stop one after the other (in theorder: belt 1, belt 2, belt 3).

If the system connected to the con-veyor belts does not provide any partsfor more than 100 seconds, there is adead time of 15 minutes, which isindicated via a lamp at Q4.

Components used

- e.g. LOGO! 24RI1 OFF button (NO contact)I2 ON button (NO contact)I3 Sensor for the detection of parts

from the system connected to theconveyor belts (NO contact)

I4 Sensor for the detection of partson conveyor belt 1 (NO contact)



Q1 Conveyor belt 1Q2 Conveyor belt 2Q3 Conveyor belt 3Q4 Indicator lamp


Other transfer times can be set asdesired.Existing systems can be easilychanged.All sensors are connected directly toLOGO!.Fewer components used than forprevious solutions.


43

Transport systemsControlling Conveyor Belts (continued)

Controlling conveyor belts with LOGO! (1)

Controlling conveyor belts with LOGO! (1)


44

Transport systemsControl of an Elevating Platform

Requirements

Control of an elevating platform hasbeen implemented with LOGO!. Sev-eral ultrasonic sensors have beenconnected in parallel to monitor theelevating platform area.

LOGO! Solution

The elevating platform can be movedup or down via pushbuttons. The UPbutton has been connected to I1 andthe DOWN button to I3. Final positionsare detected via limit switches. Limitswitch at I2 for platform UP and limitswitch at I4 for platform DOWN. Assoon as a final position has beenreached, the platform can only movein the opposite direction. The directionof movement is input to I1 or I3 via thepushbuttons. Movement of the plat-form can be halted via the STOP but-ton at I6.

The ultrasonic sensors for monitoringthe elevating platform area are con-nected to I5. If the sensors detect anobstacle, the platform is halted.Movement can be continued manuallyif the direction pushbutton is helddown for more than 2 seconds.

If, however, the emergency STOPbutton at I7 is pressed, the elevatingplatform comes to an immediatestandstill. It can then only be movedby releasing the emergency STOPbutton – the direction pushbutton isdisabled.

A warning light at Q3 is activated toprovide visual indication that the plat-form is moving either up or down.

Components used

– e.g. LOGO! 230RL

I1 Button for moving platform UP(NO contact)

I2 Limit switch up (NO contact)I3 Button for moving platform DOWN

(NO contact)I4 Limit switch down (NO contact)I5 Sensors (NC contact)I6 STOP button (NO contact)I7 Emergency STOP button

(NO contact)

Q1 Platform UPQ2 Platform DOWNQ3 Warning light


The delay times can easily beadapted to the individual situation.Simple modification/extension of thesystem without additional compo-nents.Fewer components are required thanfor a conventional solution.

Control of an elevating platform with LOGO! (1)


45

Transport systemsControl of an Elevating Platform (continued)

Control of an elevating platform with LOGO! (2)


46

Transport systemsImpregnating Textiles, Controlling theStrip Heaters and Conveyor Belts

Requirements

LOGO! can be used for impregnatingtextiles. In this process, textile balesare unrolled, put through an impreg-nating bath, and dried on heatedconveyor belts. LOGO! automaticallycontrols the conveyor belts for bothimpregnating and drying.

LOGO! Solution

The impregnation process is startedautomatically via the time switch inte-grated in LOGO!. Every day at 3:00a.m., the fans on Q1 are started toprovide ventilation. After 15 minutes,the first heated belt on Q2 starts. Theheated belts on Q3, Q4 and Q5 thenstart at five minute intervals. Becausethe heated belts need a very long timeto heat up, the first conveyor beltleading to the impregnating bath is

not put into operation until 3.5 hoursafter the heated belts have beenstarted. The second and third belts,which are connected to Q7 and Q8respectively, are then started at fiveminute intervals. When all the con-veyor belts are running, the textilesare transported to the impregnatingbath, then dried on the heated belts.Once this process has been com-pleted, the impregnation conveyorbelts and the heated belts can beimmediately stopped via the push-button on I1. The fans continue to runfor one more hour.

Components used

– e.g. LOGO! 230RL

I1 OFF button (NO)

Q1 FansQ2 Heated belt 1Q3 Heated belt 2

Q4 Heated belt 3Q5 Heated belt 4Q6 Conveyor belt 1 for impregnating

bathQ7 Conveyor belt 2 for impregnating

bathQ8 Conveyor belt 3 for impregnating

bath


LOGO! ensures that the belts startslowly and automatically, thus avoid-ing too much input current.Starting and stopping of the transportbelts is carefully coordinated.The integrated time switch makes itpossible to start heating up the dryingbelts ahead of time.The delay times are easy to change.Fewer components are required thanfor a conventional solution.

Impregnating textiles, controlling the strip heaters and conveyor belts with LOGO! (1)


47

Transport systemsImpregnating Textiles, Controlling theStrip Heaters and Conveyor Belts (continued)

Impregnating textiles, controlling the strip heaters and conveyor belts with LOGO! (2)


48

Notes


49

Machine controlCost Restraining Factor for Reversible Flow Filters

Procurement and warehousing of awide range of switching units, storageof various switching boxes, planningand manufacturing of different con-trollers are all factors, which contributeto the cost of a product. Considerablecost savings were achieved by theAugust G. Koch mechanical engi-neering company by combining con-trollers with the use of LOGO! logicmodule for reversible flow filters.The August G. Koch company in Kielproduces filters for filtration of liquids.The product spectrum extends fromplain filters through change-over filtersto fully automatic reversible flow filters,which are deployed world-wide in allbranches of industry and shipping,because of their high technical quality,safety of operation and reliability.

Reverse filtering with intervalswitching

The fully automatic AKO reversibleflow filters have a filter cartridge whichis equipped with a fabric cylinder ofthe desired gauge. The contaminationparticles of the conveyed medium arecaptured by this. For filter cleaning, aparameterizable interval control withLOGO! activates fully automaticallythe reversible rinsing process. Here agear motor is switched on and a rins-ing valve opened. The gear motorrotates the cleaning nozzle. Filteredliquid flows at great speed through thefilter fabric due to the pressure differ-ence between working pressure at theexit side of the filter and the atmos-pheric pressure in the rinsing pipe. Asa result, dirt particles withheld in thefabric are detached and carried awaythrough a rinsing valve and the con-nected rinsing pipe.

In addition to interval control, the re-verse rinsing process is activated alsoon corresponding contamination of thefabric filter. This is achieved using adifferential pressure switch connectedto a LOGO! which is triggered at adifferential pressure of approximately0.7 bar.

Fewer devices, simpler control

Automatic control of the AKO rever-sible flow filter covers only a few sim-ple operational sequences. Up to nowa multiple of control variations wereimplemented using contactor technol-ogy. Very different control boxes withdiffering standard functions had to bemade available. High pre-financingcosts and longer procurement periodswere consequently unavoidable. Withthe innovative logic module LOGO!from Siemens it is now possible toreplace the different combinations ofswitching units by a single economicalstandard product, and thereby requireonly one standard control box to bekept at the ready.

Flexibility included: Standard control cubi-cle with LOGO!.


50

Machine controlControl of a Winder

Requirements

A coiled metal strip is fed to a pressvia a winder. The strip must not de-velop slack, nor must it exceed aspecified maximum tension. If the stripbecomes too taut, the press must beswitched off.

Previous solution

Key-operated switch S1 is the modeswitch (Manual – Automatic) for thewinder. The winder motor can bejogged manually with pushbutton S2.Switches S4 and S5 monitor the ten-sion of the strip, and switch the windermotor on and off. S3 switches thepress off if the strip becomes too taut.

LOGO! solution

The circuit can be considerably sim-plified with LOGO!. It is merely neces-sary to connect the switches, the indi-cator light and the contactor for thewinder.If the mode switch is set to Manual (atI1), the winder (at Q1) can be joggedvia the pushbutton at I3. If the modeswitch is set to Automatic (at I1) thewinder is operated automatically. Thepress can be switched off again via I4.If a slack strip is detected via I6, thewinder is also switched off. Automaticoperation is indicated by an indicatorlight at Q2.

Components used

- LOGO! 24RC

I1 manual operation (normally open)I2 automatic operation

(normally open)I3 button, manual operation

(normally open)I4 switch, press Off

(normally closed)I5 switch, strip taut (normally open)I6 switch, strip slack (normally open)

Q1 winder driveQ2 indicator light, auto operationQ3 enable contacts, press


Fewer components are required thanfor the conventional solution. Thisallows a saving to be made in wiring,installation time and space in the con-trol cabinet.


K 3

S 4

S t r i p t a u t

K 1 W i n d e r

d r i v e

K 2

K 4

K 3

S 2 S 3

K 2

K 1

S 1 K 2

H 1

A u t o m a t i c

K 2e n a b l e

P r e s s

K 4

S 5

S t r i p s l a c k

L+ M I1 I2 I3 I4 I5 I6

Q1 Q2 Q3 Q4

SIEMENS

K1 H1

Winder

S3

L+

M

S1

Auto on

S2 S4 S5

Press

enable

LOGO! 24R


51

Machine controlControl of a Winder (continued)

Control of a winder with LOGO!


52

Machine controlControlling a Bending Machine

Requirements

The bending of exhaust pipes is to becontrolled using LOGO!.The bending procedure must not startunless both the pipe and connectorfitting are present.If a part is defective or not present thisis indicated by an indicator light.

LOGO! Solution

A proximity switch at I1 detectswhether a pipe is present (an ONdelay of 1 second is set for this pur-pose). Then the pipe is clamped inposition via the solenoid valve at Q1. Ifthe connector fitting is also present

(sensor at I2), the pipe is let go andthe go-ahead for bending given byresetting the enable relay at Q2(Q2 = 0).An enable procedure lasts for amaximum of 5 seconds. This is thelimit time for enabling. If no pipe isdetected within these 5 seconds thego-ahead for the bending procedureis canceled by setting the enable relay(Q2 = 1).If a part is recognized as being defec-tive or incomplete this is indicated viaan indicator light at Q3. Via I3 the errorcan be acknowledged and the defec-tive part removed. The pipe is let goand the procedure can start againfrom the beginning.

Components used

- e.g. LOGO! 24RI1 Sensor "pipe present"

(NO contact)I2 Sensor "connector fitting present"

(NO contact)I3 Error acknowledgment button

(NO contact)

Q1 Solenoid valve for clampingcylinder

Q2 Enable relayQ3 Error indicator lamp


Can be easily expanded; for examplefor additional displays.Fewer components are needed thanfor previous solutions.

Controlling a bending machine with LOGO!


53

Machine controlControlling a Cream Stirrer

Requirements

A cream stirrer in a dairy is to be con-trolled using LOGO!. Automatic ordirect operation can be selected via amode selector switch. Faults are indi-cated via a fault indicator lamp and analarm horn.

LOGO! Solution

If the mode selector switch is set at"automatic" (I1), the stirrer (at Q1)starts up immediately. Automatic op-eration means that the stirrer switcheson and off after set intervals (15 sec-onds ON, 10 seconds pause). Thestirrer operates at these intervals untilthe mode selector switch is set at 0.With direct operation (I2 set at "direct")the stirrer runs without time intervals.

If the motor circuit-breaker is tripped(at I3) the fault indicator lamp (Q2)and alarm horn (Q3) are activated.The intervals between the horn signalsare set using the clock-pulse genera-tor at 3 seconds. The horn signal canbe interrupted via the reset button atI4. When the fault has been rectifiedthe fault indicator lamp and the hornare reset.

With the "alarm function test" button atI5 both the fault indicator lamp and thehorn can be tested.

Components used

- e.g. LOGO! 230RI1 Mode selector switch set at

"automatic" (NO contact)I2 Mode selector switch set at

"direct" (NO contact)I3 Motor circuit-breaker alarm

contact (NO contact)I4 Horn reset button (NO contact)I5 Alarm function test button

(NO contact)

Q1 StirrerQ2 Fault indicator lampQ3 Alarm horn


The stirring intervals can be changedas desired.Fewer components are necessarythan for previous solutions.

Controlling a cream stirrer with LOGO!


54

Machine controlSequence Control of Machines for Welding Cables of LargeCross-section

Requirements

The sequence of operations of cable-welding machines must be strictlyadhered to. Activation is only possiblevia a foot-operated button. In the caseof improper operation, the cycle isimmediately interrupted and must startagain from the beginning.

LOGO! Solution

The welding procedure is initiated bya foot-operated button at I1. Improperoperation and delay on the part of theoperator must be excluded. When thefoot-operated button is pressed, theend of the cable is pushed up to theend stop. The foot-operated buttonmust be pressed again within 3 sec-onds to clamp the cable ends (valveat Q2).

The time period of 3 seconds is indi-cated via a signal lamp at Q1. If thefoot-operated button is pressed againwithin the 3 seconds, welding takesplace. When the foot-operated buttonis pressed again the cable is freedand transported further (valve at Q3).If the 3 seconds are exceeded afterthe foot-operated button was firstpressed, the clamping valve immedi-ately lets go of the cable and it is notwelded. The cycle must start againfrom the beginning.

Components used

- e.g. LOGO! 24RI1 Foot-operated button

(NO contact)Q1 Signal lamp of the preset time

(3 sec.)Q2 Valve for clamping the cableQ3 Valve for freeing the cable


The preset time can be adapted to fitthe circumstances at any time.With LOGO! this circuit, which previ-ously needed numerous componentsin a 3-row sub-distribution, is a space-saving and low-cost solution.

Sequence control of machines for welding cables of large cross-section with LOGO!


55

Machine controlControl of Several Pumps/Pump Pairswith Centralized Operator Control and Visualization

Requirements

LOGO! is to be used as an AS-Interface slave to control severalpump pairs. The centralized operatorcontrol and visualization functions areimplemented in the control room witha SIMATIC S7-200 as an AS-Interfacemaster connected to a TD 200 for thedisplay of messages for each pumppair.

LOGO! Solution (for one pumppair)

LOGO! either controls the two pumpsdirectly or allows them to be operatedmanually via the AS-Interface bus. ALOGO!Contact module is connectedto output Q1 for switching pump 1 anda second LOGO!Contact module isconnected to output Q2 for pump 2.

Manual/automatic mode:The manual/automatic switch is con-nected to the S7-200 in the controlroom. The switching status is trans-ferred to LOGO! via the AS-Interfacebus (AS-i input Ia1).In automatic mode, the pumps areactivated in accordance with the fill-level that has been reached (see de-scription of the fill-levels).If the switch is set to manual, eachpump can be switched on and offfrom the control room as well as on-site. The status of the switches in thecontrol room are transferred to theslaves via the AS-Interface bus wherethey are read as signals Ia2 for pump1 and Ia3 for pump 2.The on-site switches are directly con-nected to LOGO!. The switch forpump 1 is connected to I1 and theswitch for pump 2 is connected to I2.

Fill-level 1:The float switch for level 1 is con-nected to I5. When this trips, thepumps operate alternately for 5 min-utes each.

Fill-level 2:The float switch for level 2 is con-nected to I6. When this trips, thepumps operate simultaneously for 8minutes followed by a break of 2 min-utes.

Fill-level 3:The float switch for level 3 is con-nected to I7. When this trips, bothpumps operate continuously.

Indicators:Lamps are connected to outputs Q3 toQ5 to indicate the fill-levels (Q3 forlevel 1, Q4 for level 2 and Q5 for level3). The lamps connected to Q6 andQ7 indicate whether the pumps arerunning or not.

Faults:Faults are monitored via the normally-closed contacts of the respectiveLOGO! Contact module. The check-back signal is input on I3 and I4. If afault occurs when the pump should beoperating, the appropriate lamp on Q6or Q7 flashes.

Checkback signals:Checkback signals are transferred tothe S7-200 (master) via the AS-i out-puts. Faults on pump 1 (Qa1), faultson pump 2 (Qa2) and fill-level 3 (Qa3)are reported.The checkback signals can then beused in further processing, for exam-ple, for displaying messages on theTD200 or for flashing lamps in thecontrol room.

Components used

- LOGO! 24RLB11

I1 Manual pump 1 (NO)I2 Manual pump 2 (NO)I3 Checkback signal, pump 1 (NC)I4 Checkback signal, pump 2 (NC)I5 Float switch, fill-level 1 (NO)I6 Float switch, fill-level 2 (NO)I7 Float switch, fill-level 3 (NO)Ia1 Manual/automatic switch,

control roomIa2 Manual pump 1, control roomIa3 Manual pump 2, control room

Q1 LOGO!Contact pump 1 (NC)Q2 LOGO!Contact pump 2 (NC)Q3 Indicator, fill-level 1Q4 Indicator, fill-level 2Q5 Indicator, fill-level 3Q6 Indicator, pump 1Q7 Indicator, pump 2Qa1 Fault pump 1Qa2 Fault pump 2Qa3 Overflow (fill-level 3)


The installation can easily be ex-panded with additional pump pairs orother subsystems.In the event of a bus fault or failure ofthe central controller, LOGO! contin-ues to operate and activates thepumps.This results in enhanced reliability.LOGO! implemented as an AS-Interface slave provides distributedintelligence on-site. This allows thepumps to be activated manually (e.g.for test purposes).Standard actuators and sensors canbe used.The operating times for the pumps areeasily adapted and modified.Fewer components are required thanin the case of previous solutions.


56

Machine controlControl of Several Pumps/Pump Pairswith Centralized Operator Control and Visualization (cont.)

Control of several pumps/pump pairs with centralized operator control and visualization with LOGO! (1)



57

Machine controlControl of Several Pumps/Pump Pairswith Centralized Operator Control and Visualization (cont.)



58

Machine controlCutting Tool, e.g. for Fuses

Requirements

LOGO! is to be used to implement acutting tool for the fuses of fireworks.Short lengths are to be cut as quicklyas possible from safety delay fuses of5 meters in length. For this purpose,the fuse must be transported a certaindistance to the cutting position. Whena preset quantity has been cut, theprocedure is automatically stopped.

LOGO! Solution

The fuse is transported and cut usingtwo cylinders that transport the fuseand cut it respectively by means ofoutward travel. A solenoid valve isconnected to Q2 that ensures that thecylinders return to their initial position.The equipment is switched on bypressing the start button connected toI1. This activates the solenoid valve onQ2 and the cylinders move into theinitial position. The checkback signalthat reports that the transport cylinderis in the initial position is output by theinductive switch connected to I3.When this trips, the cylinder for trans-porting is activated on Q3. The cylin-der moves outwards and transportsthe length of fuse with it. The length isdetermined by the extension range of

the cylinder. When the final position isreached, the inductive switch”Transport cylinder extended” on I4trips. Then the cylinder for the cuttingprocess is activated on Q4. Thismoves outwards and cuts the fuse.When it reaches the final position, acheckback signal is output by theinductive switch ”Cutting cylinderextended” on I5. This causes Q3 andQ4 to be reset and the procedurebegins again.The quantity counter integrated intoLOGO! can be used to count theseparate cutting procedures. Forevery cut, the counter is incremented.When the preset quantity of 80 isreached, the cycle is not startedagain. This is indicated by the LED onQ1.To restart the cutting cycle and toreset the counter value, the OFF but-ton on I2 must be pressed for morethan 2.5 seconds.

If the OFF button or the EmergencySTOP button on I6 is pressed, theprocedure is interrupted and the cyl-inders are halted in the initial position.The counter value is retained and thesolenoid valve on Q2 is switched off.

Components used

e.g. LOGO! 230R

I1 Start button (NO)I2 OFF button (NO)I3 Inductive switch

”Transport cylinder home” (NO)I4 Inductive switch

”Transport cylinder extended”(NO)

I5 Inductive switch”Cutting cylinder extended” (NO)

I6 Emergency STOP button (NC)

Q1 LED ”Quantity reached”Q2 Solenoid valve (for initial position)Q3 Cylinder for transportingQ4 Cylinder for cutting


The maximum quantity can be dis-played and modified easily.Two functions could be assigned tothe STOP button (interrupt procedureand reset counter).Fewer components are required thanfor a conventional solution.


59

Machine controlCutting Tool, e.g. for Fuses (continued)

Cutting tool, e.g. for fuses controlled by LOGO! (1)

Cutting tool, e.g. for fuses controlled by LOGO! (2)


60

Machine controlChangeover Circuit Example with two Compressors

Requirements

Two compressors are to be operatedalternately from one AC circuit. If onecompressor fails, the other one is tobe started automatically. The com-pressors can be run individually inmanual or automatic mode. LOGO!executes the control and interlockingof both compressors.

LOGO! Solution

A selector switch is provided for eachcompressor to select the manual orautomatic mode. For compressor 1,the manual setting is connected to I1,and the automatic setting to I2. Themanual setting of the second selectorswitch is connected to I3, and theautomatic setting to I4.

When one of the compressors isstarted, the main contactor is firstactuated for enabling, and the com-pressor is then started via a floatingcontact after a delay of 2 seconds. Forcompressor 1, the contactor is con-nected to Q1, and starting is enabledvia Q3. For compressor 2, the con-tactor is connected to Q2, and startingis enabled via Q4.

Manual operation:Only one compressor can be oper-ated in manual operation. For com-pressor 1, the selector switch must beset to "Manual" (to I1) and the selectorswitch of the second compressor mustbe at the 0 setting. If compressor 2 isto be operated in manual mode, theselector switch must be set to "Man-ual" (to I3) and selector switch 1 mustbe at the 0 setting.

Automatic mode:Both compressors are to be operatedalternately in the automatic mode. Thisrequires that both selector switchesbe set to "Automatic" (to I2 and I4).During the day, from 7:00 a.m. to6:00 p.m., compressor 1 is to run ifthere is sufficient pressure. A pressuremonitor is connected to I5 for thepurpose. If there is still sufficient pres-sure, a changeover to compressor 2takes place during the time from6:00 p.m. to 7:00 a.m.. Before thechangeover can take place, however,the run-on time of the compressorsmust elapse. A run-on time of 50 sec-onds is preset for compressor 1, and25 seconds for compressor 2.

If one of the compressors fails be-cause of inadequate pressure, achangeover to the other compressortakes place automatically. Even ifthere is sufficient pressure onceagain, this compressor can only beswitched off if both selector switchesare set to 0. The automatic mode mustthen be selected again.

If I5 responds because of insufficientpressure, this is signaled via the faultlamp at Q7. The fault can be acknowl-edged with I6. If the pressure remainsbelow the preset value for more than 2minutes, a flashing light responds atQ8. This alarm signal persists untilthere is sufficient pressure onceagain.

Components used

- LOGO! 230RC

I1 Selector switch, compressor 1Manual

I2 Selector switch, compressor 1Automatic

I3 Selector switch, compressor 2Manual

I4 Selector switch, compressor 2Automatic

I5 Pressure monitorI6 Acknowledgment button, fault

lamp

Q1 Contactor, compressor 1Q2 Contactor, compressor 2Q3 Start compressor 1Q5 Start compressor 2Q3 Fault lampQ4 Indicator lamp


The different run-on times of the com-pressors can be easily changed andadjusted.The operating times of the compres-sors can be easily changed via thetime switch integrated in LOGO!.

Fewer components are used than withconventional technology. This resultsin lower hardware costs and a consid-erable saving in space.


61

Machine controlChangeover Circuit Example with two Compressors (cont.)

Changeover circuit example with two compressors controlled by LOGO! (1)

Changeover circuit example with two compressors controlled by LOGO! (2)


62

Machine controlChangeover Circuit Example with two Compressors (cont.)

Changeover Circuit Example with two Compressors controlled by LOGO! (3)


63

Machine controlIntelligent Pedal Control for Selecting Speeds

Requirements

A pedal control can be used at a ma-chine workplace to select a differentmotor speed or to switch off the ma-chine. LOGO! handles this control.

LOGO! Solution

The pedal control of the machine hastwo contacts which are connected toLOGO! in the following way: Pedalcontrol ”semi-depressed” at I1 andpedal control ”completely depressed”at I2. For normal operation, motorspeed 1 is sufficient and can bestarted by pressing I1. Motor speed 1is controlled via output Q1 after adelay time of 2 seconds. If a fasterspeed is required for operation, motorspeed 2 can be selected by againpressing I1.

Motor speed 2 is controlled via outputQ2 also after a delay time of 2 sec-onds. If I1 is pressed again, the speedis again reduced. In other words, eachtime I1 is pressed the speed changesto either speed 1 or speed 2, in eachcase after a delay time of 2 seconds.An indicator light at Q3 lights up if themachine is operating at the higherspeed.In order to stop the machine, thepedal control must be depressedcompletely. The machine is thenswitched off via I2.

Components used

– e.g. LOGO! 24R

I1 Semi-depressed pedal controlchanges speed

I2 Completely depressed pedalcontrol stops machine

Q1 Motor speed 1Q2 Motor speed 2Q3 Indicator light for motor speed 2


The delay times can easily beadapted to the individual situation.Fewer components are required thanfor a conventional solution.Simple and fast modification/extensionof the function without additional com-ponents.

Intelligent Pedal Control with LOGO! for Selecting Speeds


64

Machine controlPump Control

Requirements

LOGO! has the task of controlling twopumps which adjust the level in a tankor pit. One or two pumps are to runaccording to the level, which is meas-ured via three level gauges. To ensurethe equal utilization of the pumps, achangeover from one pump to theother takes place after a preset oper-ating time.

LOGO! Solution

If the first two level gauges at I1 and I2respond, the first pump at Q1 muststart after a short delay of 2 seconds.If the third level gauge at I3 also re-sponds, the second pump at Q2 mustalso start after a delay of 2 seconds.Flags M1 and M2 are used to decidewhether one or two pumps are to run.

After 2 hours' operating time of thefirst pump, an automatic changeoverto the second one takes place. Theoperating time is registered with thehours-run gauge. The changeovertakes place via the RS flip-flop (block17). This also occurs when the secondpump has run for 2 hours. The entireoperating time of the pumps can beread off the hours-run meter.

Before any pump is started, the sys-tem pressure is tested (at I4). If it isnot reached within 5 seconds, bothpumps run until the low level (levelgauge 1) is reached. Simultaneously,a fault message is emitted at Q3(flashing light) and Q4 (steady light).The pumps and fault message canalso be reset manually via I5.

Components used

- e.g. LOGO! 230RC (...0BA1)

I1 Level gauge 1 (normally open)I2 Level gauge 2 (normally open)I3 Level gauge 3 (normally open)I4 Pressure switch (normally open)I5 Reset (normally open)

Q1 Pump 1Q2 Pump 2Q3 Fault message, flashing lightQ4 Fault message, steady light


The cost of this solution is far lowerand it is more flexible than the previ-ous conventional or tailored, electronicsolution.

Furthermore, it can be easily modifiedto add new characteristics; for exam-ple,• to detect whether any incorrect

combination of the level gaugesoccurs. This can be used as a faultmessage and/or to shut down thecontrol system.

• Or to ensure that the pumps run fora minimum time after starting (ad-ditional Off-delays).


65

Machine controlPump control (continued)

Pump control with LOGO!


66

Machine controlPressure-dependent Switching offand Activation of Pumps/Fans

Requirements

The pressure or flow in a system is tobe controlled with five pumps or fans.The first pump/fan (master) is con-trolled via an external inverter (fre-quency converter). The remaining four(slaves) are controlled via LOGO! (atpreset speeds). The external inverteris responsible for the entire PID con-trol throughout the system. LOGO!ensures that the four slaves are acti-vated and switched off in accordancewith the inverter. Equal utilization ofthe pumps is also ensured.

LOGO! Solution

The external inverter has two pro-grammable relay outputs. These areset so that they emit a signal when theinverter output has reached >=50 Hzor <= 20 Hz. A slave is to be activatedat >=50 Hz, and a slave is to beswitched off at <=20 Hz. The corre-sponding slaves (Q1 to Q4) areswitched on and off in accordancewith the two frequency values and theduration of the signal. This is imple-mented via counters and bit memo-ries.

If input I1 (>=50 Hz) is on for 1 s andthe maximum count (B06 or M4) hasnot yet been reached, all four countersare incremented by 1. If input I2(<=20 Hz) is on for 1 s, all four count-ers are decremented by 1. Thecounting direction is specified viablock B02. Inputs I1 and I2 arescanned every 10 s.

The latest counts between 0 and 4 arestored via bit memories M1 to M4. Ifthe latest count is 3, for example, bitmemories M1, M2 and M3 are on.Outputs Q1 to Q4 are then set ac-cording to the bit memories: startingwith Q1 for the first time, and startingwith Q4 for the second time. This en-sures equal utilization of the slaves.Reversal of the order is implementedvia block B14 (current impulse relay).The order can be changed manuallyvia I3.

A typical sequence could be as fol-lows:• The system demand is initially 10%;

the master pump/fan runs at a me-dium frequency and the slavepumps are switched off.

• The system demand rises and thePID controller of the inverter auto-matically attempts to reach the re-quired frequency. If the value of50 Hz is reached, a signal is emit-ted to LOGO! (input I1). After adelay of 1 s, the first slave isswitched on. The master is relievedwith this slave support and the fre-quency drops to a lower value. Ifthe frequency does not drop within10 s, the next slave is added untilall slaves are running.

• The system demand decreases andthe PID controller of the inverterautomatically attempts to reach thelower frequency. If the value of20 Hz is reached, a signal is emit-ted to LOGO! (input I2). After adelay of 1 s, one slave is switchedoff. Without the support of theslave, the frequency of the masterrises again. If the frequency doesnot rise within 10 s, the next slave isswitched off until none is runningany longer.

Components used

- e.g. LOGO! 230RC (...0BA1)- External inverter

I1 Inverter output >=50 Hz(normally open)

I2 Inverter output <=20 Hz(normally open)

I3 Manual sequence (normally open)

Q1 Pump/fan 1Q2 Pump/fan 2Q3 Pump/fan 3Q4 Pump/fan 4


In comparison with the special solu-tions available at present, this solutionis simple, flexible and effective.Additional characteristics such as analarm and automatic running of thepumps (to prevent seizure) can beeasily added.If a pump/fan is removed for mainte-nance, its absence is automaticallycompensated for, simply by selectingthe next slave.


67

Machine controlPressure-dependent Switching offand Activation of Pumps/Fans (continued)

Pressure-dependent switching off and activation of pumps/fans with LOGO! (1)

Pressure-dependent switching off and activation of pumps/fans with LOGO! (2)


68

Machine controlActivation of Up/Down (Right/Left) Movementwith only one Momentary-Contact Switch

Requirements

Up and Down movements or Rightand Left operation − of shutters ordoors, for example − are to be acti-vated with only one momentary-contact switch.

LOGO! Solution

The application is explained hereusing the example of shutter control.A momentary-contact switch is con-nected to I1 for starting and stoppingthe Up and Down movement. Q1 isused to activate the "Close shutter"operation, and Q2 the "Open shutter"operation. The final position of theshutter is interrogated via two limitswitches at I2 for "open" and at I3 for"closed".

If the shutter is open and the momen-tary-contact switch is pressed, Q1 isselected to lower the shutter. Whenthe final position is reached, the limitswitch turns Q1 off. If the momentary-contact switch is pressed again, theopposite direction − that is, for open-ing − is activated. This takes place viaQ2 until the limit switch at I2 responds.The momentary-contact switch inter-rogation is implemented with a currentimpulse function.If the shutter is not to be operated tothe final position but only half way, forexample, this is also achieved with themomentary-contact switch at I1. Theshutter is stopped. When I1 is pressedagain, it starts moving again but in theopposite direction. Output Q3 is usedas a bit memory to interrogate for theprevious direction.

Components used

- LOGO! 230R

I1 Momentary-contact switch (nor-mally open)

I2 Limit switch "open" (normallyclosed)

I3 Limit switch "closed" (normallyclosed)

Q1 DownQ2 UpQ3 Used as a "bit memory"


LOGO! allowed this application to beimplemented easily and at low cost. Aconventional solution would be con-siderably more complicated.Significantly less space is needed withLOGO!.

Activation of up/down (right/left) movement with only one momentary-contact switch controlled by LOGO! (1)


69

Machine controlActivation of Up/Down (Right/Left) Movementwith only one Momentary-Contact Switch (continued)

Activation of up/down (right/left) movement with only one momentary-contact switch controlled by LOGO! (2)


70

Machine controlSequence Timer

Requirements

LOGO! is to be used to turn on and offa series of outputs in a sequence atypical requirement in many simpleprocess applications. There are 15time intervals and each Output canhave up to 3 on periods in the cycle.

LOGO! Solution

When an initial start pulse is given, asequence of 15 cascading timers isinitiated. Each timer is set at 1s asdefault be all are independently ad-justable from 50mS to 99.99 Hrs. Thesequence can be cancelled, and alloutputs turned off, at any time bygiving a stop pulse. At the end of thesequence B02 sends a pulse to reini-tiate the sequence via B34. If it isdesired, B02 can de deleted makingthe system non repeating.

The system would restart after a stopsignal (or power restoration) followedby a new start signal.

To put the system into use, first set thetimers to suit the actual process to becontrolled. If less than 15 timers arerequired, simply set the remainder to00.00s. To turn an output on at a par-ticular point in the sequence, use the‘connect’ tools to connect one of therelated XOR gate inputs to the re-spective timer or marker output. Toend that particular on period, link theother input of the same XOR gate to alater timer or marker output.

Each output can have up to 3 on peri-ods within the sequence. This can beincreased by adding additional ORand XOR gates. Any unused XORblocks will be left without an input andso will have no effect on the pro-gramme.

Components used

- e.g. LOGO! 230RC (...0BA1)

I1 Start Push Button (NO Contact)I2 Stop Push Button (NO Contact)

Q1 Desired output device 1Q2 Desired output device 2Q3 Desired output device 3Q4 Desired output device 4


This system provides a very simple,yet flexible, sequence controller whichis likely to be less expensive thaneither specialist sequence controllersor relay timer combinations.Additional features such as real timeclock and day / date initiation can beeasily added.


71

Machine controlSequence Timer (continued)

Sequence timer with LOGO!


72

Machine controlCam Timer

Requirements

LOGO! is to be used to turn on and offa series of outputs in a sequence atypical requirement in many simpleprocess applications. However, ifpower is lost, the system must re-member where it was and restartautomatically from that position onrestoration of power.

LOGO! Solution

When a Run signal is present (I1),Clock pulse B01 (default setting 1sbut adjustable from 50mS to 99.99Hrs) is fed to a series of AND gates.Once Counter 1 preset is reached, thecount pulses are fed onto Counter 2and so on, until eventually Counter 7output comes on and resets all thecounters and we start again. Eachcounter is set to 5 as default but canbe adjustable independently from 0 to999999. The sequence can be can-celled, and all outputs turned off, atany time by giving a reset pulse (I2).

The put the system into use, first setthe clock pulse counters to suit theactual process to be controlled. If lessthan 7 counters are required, simplyset the remainder to 0. To turn anoutput on at a particular point in thesequence, use the ‘connect’ tools toconnect one of the related XOR gateinputs to the counter or marker output.To end that particular on period, linkthe other input of the same XOR gateto a later timer or marker output.

Each output can have up to 3 on peri-ods within the sequence. This can beincreased by adding additional ORand XOR gates. Any unused XORblocks will be left without an input andso will have no effect on the pro-gramme.

Components used

- e.g. LOGO! 230RC (...0BA1)

I1 Run/Stop Signal (NO Contact)I2 Reset Push Button (NO Contact)

Q1 Desired output device 1Q2 Desired output device 2Q3 Desired output device 3Q4 Desired output device 4


This system provides a very simple,yet flexible, Cam Timer.It is much easier to adjust than stan-dard mechanical Cam Timers. Addi-tional features like timers and real-timeoperation can be added.It can be used for a voltage and fre-quency within the LOGO!s range. Forexample the 230RC could be used onany voltage from 85-265 50 or 60 Hz.Conventional Cam Timers can onlyoperate on one voltage and fre-quency.


73

Machine controlCam Timer (continued)

Cam timer with LOGO!


74

Machine controlControlling a Silo-Filling System

Requirements

LOGO! can be used to control andmonitor silo-filling systems. The silosare filled with lime or cement fromtrucks via a hose.

LOGO! Solution

The filling process can be started onlywhen the enabling button on I1 isactuated and the hose properly con-nected. A reed contact on the fillerneck signals whether the hose isproperly connected to the silo. Thissignal is read into LOGO! via input I2.The compression valve on Q2 is thenopened, the venting filter on Q1 beingtriggered simultaneously. The ventingfilter must remain on throughout thefilling process. Lime or cement cannow be pumped into the silo.

The level indicator on I3 signals whenthe silo is full.

An audible alarm signals that 99 sec-onds remain until automatic termina-tion of the process. The valve on thetruck must be closed within this timeperiod in order to allow emptying ofthe hose. The audible alarm can bemanually reset via the acknowledg-ment switch on I6; otherwise, it will beswitched off automatically after 25seconds.

If the hose could not be emptied intime, a 30-second emergency fillingprocedure can be activated using thebutton on I5.

An overpressure monitor in the siloalso terminates the filling procedureautomatically. This is signaled by theindicator lamp on Q4.

Components used

- LOGO! 230R

I1 Enabling button (NO)I2 Reed contact on filler neck (NO)I3 Level indicator (NO)I4 Overpressure monitor (NC)I5 Emergency fill button (NO)I6 Acknowledgment switch for

audible alarm (NO)

Q1 FilterQ2 Compression valveQ3 Audible alarmQ4 Indicator lamp for overpressure


The application can be used for othersilos, as it is a standard application.It requires less space than the previ-ous solution.Fewer components are required thanfor a conventional solution.

Controlling a silo-filling system with LOGO!


75

Special solutionsLOGO! 12RC in Warning Boards on French Motorways

Problems caused by error-pronerelay controllers in variable traf-fic notice boards were solved byASF (Société des autoroutes dusud de la France ) in an intelligentmanner: The French motorwaycompany deploys LOGO! 12RCin more than 30 such boardsalready.

The variable boards, which, for exam-ple, warn motorists of roadworks orhazardous points, are set up with theaid of triangular panels which arerotated using motors. Before the intro-duction of the logic module, technici-ans had to frequently check things onsite since the boards often becameblocked. The cause was usually adefect in the relay controller. For theapplication, which used a 12-voltbattery, the company EAI Industry(Bagnol/Cèze DE LA Gard) deployedthe LOGOS! 12RC relay controller asan innovative solution.

Simultaneously with the changeover toLOGO! a prototype was developedwhich withstands the hard conditionsencountered along the side of themotorway and which eliminates theprevious problems. Moreover LOGO!constituted a far more economicalsolution. The Siemens logic modulealone actually replaces in this appli-cation nine timer switches and fourcounters, not taking the time and pro-ductivity savings during installation ofthe control boxes into account. In ad-dition, LOGO!, by virtue of its easyadaptablility, considerably simplifieshandling of the system and thus meetsall requirements in an ideal manner.

As the largest motorway company inFrance, ASF maintains a road networkof 2028 kilometers. A further 582 kilo-meters are currently being construc-ted. To guarantee and expand safetyon its routes is a matter of high prioritywith ASF. For all infrastructure facilitieson its routes the company always aimsto use equipment that incorporates themost innovative technology and cor-responds to the state of the art.

Today therefore, more than 30 vari-able boards are already equippedwith reliable Siemens LOGO! units.And the logic module can probablylook forward to a sunny future on themotorways of the south. In the fore-seeable future it is expected that alltraffic boards of ASF will be upgradedwith LOGO!

The variable boards are set up with the aidof triangular panels which are rotated usingmotors


76

Special solutionsControl of Automatic Feeders,for Example for Trout

Requirements

The automatic feeders in a fishpondsystem are to be controlled withLOGO!. The trout are fed at differenttimes according to their size and age.When the feed containers are empty,the feeder should be switched off toprevent unnecessary discharge of thebattery.

LOGO! Solution

Three automatic feeders are con-trolled with LOGO!. A feeder consistsof a conical container with a 12-Vmotor for the spreader disk. The coni-cal container shape and the vibrationof the motor ensure that feed is alwaysadvanced.

Automatic feeder 1 at output Q1 feedsthe brood. Feed is to be providedhourly every day from 8:00 a.m. to6:00 p.m.. A pulse can be generatedevery hour simply by means of theintegral time switch and the pulsegenerator (set time = 30 minutes). Theissuing of feed is enabled for only 2seconds via the On-delay. However,feed is only issued when the Onswitch at I1 is actuated and the levelindicator at I4 signals "full".

A lower switching frequency is suffi-cient for the young fish and edibletrout. Thus the second feeder at Q2 isactivated for 2 seconds daily for theyoung fish at 12:00 noon and at4:00 p.m. and at 8:00 a.m. on theweekend.For the edible trout, feed is output viafeeder 3 at Q3 from Monday to Satur-day at 9:00 a.m. and at 3:00 p.m..Feeders 2 and 3 also issue feed whenthe On switch at I2 or I3 is actuatedand the level indicator at I5 or I6 sig-nals "full".If one of the feeders is empty, this issignaled via the level indicators at I4,I5 or I6 and an indicator lamp at Q4lights up.

Components used

- LOGO! 12RC

I1 On switch, feeder 1(normally open)



I4 Level indicator, feeder 1(normally closed)



Q1 Automatic feeder 1Q2 Automatic feeder 2Q3 Automatic feeder 3Q4 Indicator lamp


The individual switching times can beeasily changed.Sufficient switching cycles can begenerated simply with the internalpulse generator.Since many breeding tanks arepopulated with fish of the same varietyin large installations, the switchingprogram can be simply used again.By means of LOGO! 12RC, the auto-matic feeders can be used without ACpower (battery-powered).Fewer components are used than withthe conventional technology.


77

Special solutionsControl of Automatic Feeders,for Example for Trout

LOGO! control of automatic feeders, for example for trout (1)

LOGO! control of automatic feeders, for example for trout (2)


78

Special solutionsKilling Germs with Gas

Requirements

LOGO! can be used in hatcheries. Inthese installations, LOGO! controls thegas used to kill germs on the eggs. Ina special chamber, gas is generatedusing an electric heating device. Thegas must be present in the room for adefined period of time; the chamber isthen cleared by an exhaust fan.

LOGO! Solution

The gassing process is started bypressing the pushbutton on I1. Thegas generator on Q1 is activated im-mediately. It is switched off after 10minutes via a n OFF delay. The gas-sing period depends on the size of thechamber. The gas must remain in theroom for a certain period of time inorder for it to successfully completethe germ-killing process. After 10minutes, the exhaust fan on Q2 isactivated and the chamber cleared ofgas The fan also runs for 10 minutes

before being turned off via a trippingdelay. A mode indicator on Q3 signalsthat the gassing process is in prog-ress.The process can be stopped at anytime by pressing and holding I1 forlonger than three seconds. OutputsQ1 to Q3 and all timers are reset.Block B11 ensures that stopping theprocess will not result in outputs Q1and Q2 being set arbitrarily. The pro-gram can be restarted via I1 afterevery cycle and every interruption.Independently of the program run, theexhaust fan can be switched on andoff via I2. This is made possible by acurrent impulse function.

Components used

– e.g. LOGO! 230R

I1 ON/OFF button (NO)I2 Exhaust fan ON/OFF (NO)

Q1 Gas generatorQ2 Exhaust fanQ3 Mode indicator


The gassing and ventilating times canbe readily adapted to the size of thechamber, thus making it easy to usethe same program for other installa-tions.Easy double usage of pushbutton I1(can be used for switching the proc-ess on and off).

Fewer components are required thanfor a conventional solution.


79

Special solutionsKilling Germs with Gas (continued)

LOGO! control of killing germs with gas


80

Notes

Exclusion of liability

We have examined these contents of the publication for agreementwith the described hardware and software. However, deviationscannot be ruled out and we therefore offer no guarantee ofcomplete agreement. The details in this publication are checkedregularly and necessary corrections are contained in the subse-quent editions.

Siemens AGAutomation and DrivesP.O. Box 48 48D-90327 NurembergAllemagne

Siemens AktiengesellschaftFee: € 1,00

© Siemens AG 2000Subject to change without prior notice

N° de ref. 6ZB5310-0JA02-0BA0Printed in Germany26100/001429 MAN 090010.

LOGO! at a glance

LOGO!Basic / LOGO!Pure Versions6/8 inputs, 4 outputs; 72 (4 modular spaces) x 90 x 55 mm (W x H x D)R: Relay outputs, C: Clock, o: without display

• 12/24RC 6ED1 052-1MD00-0BA2• 24 6ED1 052-1CC00-0BA2• 24RC 6ED1 052-1HB00-0BA2• 230RC 6ED1 052-1FB00-0BA2• 12/24RCo 6ED1 052-2MD00-0BA2• 24RCo 6ED1 052-2HB00-0BA2• 230RCo 6ED1 052-2FB00-0BA2

LOGO!Long / LOGO!Bus verions12 inputs, 8 outputs;126 (7 modular spaces) x 90 x 55 mm (W x H x D)R: Relay outputs, C: Clock, L: Long, B: Bus

• 12RCL 6ED1 053-1BB00-0BA2• 24L 6ED1 053-1CA00-0BA2• 24RCL 6ED1 053-1HB00-0BA2• 230RCL 6ED1 053-1FB00-0BA2• 24RCLB11 6ED1 053-1HH00-0BA2• 230RCLB11 6ED1 053-1FH00-0BA2

LOGO!Accessories (optional)

• Soft Comfort V2.0 6ED1 058-0BA00-0YC1• Upgrade V1.0 to V2.0 6ED1 058-0CA00-0YC0• PC cable 6ED1 057-1AA00-0BA0• Card yellow 6ED1 056-1BA00-0AA0• Card red 6ED1 056-4BA00-0AA0• Manual German 6ED1 050-1AA00-0AE3• Maunal English 6ED1 050-1AA00-0BE3• Manual French 6ED1 050-1AA00-0CE3• Manual Spanish 6ED1 050-1AA00-0DE3• Manual Italian 6ED1 050-1AA00-0EE3• Manual Portuguese 6ED1 050-1AA00-0GE3• Contact 24 6ED1 057-4CA00-0AA0• Contact 230 6ED1 057-4EA00-0AA0

Product designation Siemens Order No.

LOGO! right near to you

At all Siemens branches, selected electrical equip-ment wholesalers, and via catalog/mail order or onthe Internet.

LOGO! on the Internet

Here you will find Products and Downloads (including free demo software, software upgradesand off-the-shelf applications), News (such as thecustomer newspaper GO!); you can make onlinepurchases and receive personal support under Service and Dialog:www.ad.siemens.de/logo

Your local LOGO! contact partner:

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