A VERY GOOD MORNING TO ALL OF YOU

VOCATIONAL TRAINING ON DIESEL

LOCO SHEd KHARAGPURA PROJECT ON

RELAYS

Project maid by

SHESHADRI SHEKHAR RAUTH

BACHELOR OF TECHNOLOGY

IN

ELECTRICAL ENGINEERING

NARULA INSTITUTE OF TECHNOLOGY

WEST BENGAL

Acknowledgement

I take this opportunity to express my sincere gratitude to all who have helped me in the successful completion of my vocational training and this project report. I would like to say my greatest appreciation to the highly efficient and devoted technical staff, supervisors of the DIESEL LOCO SHED, KHARAGPUR.I am highly indebted to them for their tremendous support and help during the completion of my training and project report.

   

Sheshadri Shekhar Rauth

  

ContentsHistory of Diesel Loco ShedRelaysBasic design and operationType of relays used in DLSWheel Slip relayGeneral purpose relayContactor relayReferences linksConclusion                                               

History of Diesel Loco Shed

RAILWAY: SOUTH EASTERN RAILWAY SHED : DIESEL LOCO SHED, KHARAGPUR

I. Brief History

1. Year of Establishment: 1986.2. Road No / Type of the first loco homed in Shed: WDM13. Details of any heritage Locos in Shed on pedestal or

otherwise: NIL5. Type Wise Holding (as on 01-06-10): WDM 2 48WDM3A:35 WDG3A:5 WDS6: DEMU 1400 HP DPCs: 07

6. Homing Capacity: 100 locomotives

RelayA relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism mechanically, but other operating principles are also used. The first relays were used in long distance telegraph circuits.

Basic design and operation    When voltage is supplied to the primary circuit, current flows through the coil winding to ground. Whilst doing so, a magnetic field develops around the primary coil. As the magnetic field builds, it pulls together the switch contact in the secondary circuit, thus supplying current to the component being operated. When the relay is switched off the magnetic field is removed and the sprung plate returns the switch to the open circuit position, thus switching off the power.

Schematicsymbol for the relay

Switching contact

(nail)

Armature contact

Electromagnet

AA cell 1.5 v

Switch

The controlled device in this schematic is a 6 – 9 volt light bulb. You can use a DC motor or other device.

- +

 Types used in DLSWheel Slip relayA Wheel Slip relay has four terminals. Two of those are use in series operation and another two are used in parallel operation. At the starting time out of six traction motor each two are connected in series and those all three constructions are connected in parallel with a resistor. In between one pair of motors the wheel slip relay is connected in the equi-potential position.

General Purpose relay (GP)

This  type  of  relays  is  generally used  in  loco.  It  has  a  magnetic coil.  It  is  magnetized  for tripping.  It  is  a  substance  that can  make  or  break  more  than one  circuit  at  a  time.The  rating of  the magnetic  coil  is  74  v  dc, 450  ohm  at  20  degree  C.    The contact  of  the  relay  is  normally closed.  By  energizing  the magnetic coil the contact can be open. At  a time more  than one circuit can be operated through this relay.

Contactor relay

Such devices are often used for motor starters. A motor starter is a contactor with overload protection devices attached.

   References links

www.kpsec.comwww.autoshop101.comwww.oenindia.comwww.nteinc.comwww.teledynerelays.com www.circuitstoday.com www.embed4u.com www.electrical4u.com etc.

  ConclusionTraining opportunities and facilities provided to us were

adequate and helpful. Each and every department of this organization has given us full cooperation. All the instructors journey in the reputed organization.

During my training period, I have gained adequate and valuable knowledge regarding various machineries and instruments used in DLS(kgp). I hope that whatever valuable knowledge and experiences I have gained during this period, will be useful and helpful in my future professional career.