The G123-825 Buffer Amplifier is intended to interface between the output of standard signal sources, such as a PLC or servo amplifier, and a Moog servo\proportional valve. It accepts three types of signal input and can output most of the Moog servo\proportional valve signals. It has a single pole active filter to remove noise from the input signal.

PLC ±10 V and 4-20 mA inputs:The G123-825 interfaces between standard PLC analog output signals of ±10 V and 4-20 mA on the input side and the Moog valve on the output side. This solves the compatibility problem between these signals and the valve requirement.

Mechanical feedback (mfb) valve input:The G123-825 interfaces between the current output of a servo amplifier, on one side, and a Moog valve on the other. This enables old mfb valves to be replaced by modern electrical feedback (efb) valves, without changing the servo amplifier. The buffer amplifier takes the existing servo amplifier output and converts it to an efb compatible signal.

Input filter:The G123-825 has a filter to remove noise from the input signal. The filter time constant is switch selectable. The switch selections sum, so a large variety of time constants is available.

Outputs:The output signals are switch selectable. They are:

4 to 20 mA fixed. Suitable for efb valves• 0 to ±10 V fixed. Suitable for efb valves• 0 to ±5 to ±100 mA switch selectable. Suitable for mfb valves. • Suitable for efb valves when set to ±10 mA

The output current selector switches can have more than one selected, so the selected values sum. For example, selecting 30 and 50 mA together gives a full scale output of ±80 mA.The buffer amplifier is housed in a compact DIN rail housing and requires a 24 VDC supply. Front panel test points and valve drive LEDs facilitate commissioning and trouble shooting.

ADVANTAGES Switch selectable input signals• Switch selectable outputs signals • to suit most Moog valves Switch selectable input filter• Vv and Iv LED valve drive indicators• Valve drive signal test point• Compact DIN rail mounting• 24 VDC supply• CE marked•

G123-825-001BUFFER AMPLIFIER

WHAT MOVES YOUR WORLD

SPECIFICATIONS

Moog has offices around the world. For more information or the office nearest you, contact us online.

e-mail: info@moog.com

www.moog.com/industrial

Moog is a registered trademark of Moog Inc. and its subsidiaries. All trademarks as indicated herein are the property of Moog Inc. and its subsidiaries. ©2010 Moog Inc. All rights reserved. All changes are reserved.

DIN Buffer Amplifier Moog Aust/PDF/0211

This technical data is based on current available information and is subject to change at any time by Moog. Specifications for specific systems or applications may vary.

+15V

-15V0VTP

Power Supply

1

2+24V

0V

0.22mS (723Hz)

2.2mS (72Hz)

4.7mS (34Hz)

10mS (16Hz)

22mS (7Hz)

100K

1K

LowRinswitch

Input

0Vref

3

Valve Command Filter LED

Vv

V

Voltage Amplifier

Current Amplifier

5mA

10mA

20mA

30mA

50mA

Output currentselect switches

Output

TPvalve

10

9

14

LED

Iv

Voltage

select

+24V

13

6

5

Filterselectswitches

+

+

+

100K

+24VSupply

PLC

see note 3

(4 switches)Valve

Current

_

0Vref

4

7

8Input

6

PLC/Servoamp

7

+

50R

R25 R21

mfbConverter

4-20mA

mfb

10V+

4-20mAConverter

see note 3

Notes:

2. Terminal 10 max output current

3. R21 and R25 are 1/4W plug-in4-20mA output

select(2 switches)

Fuse250mA T

See note 1

See note 1

See note 1

LED

Vs

11

12

15

16

+15V

-15V

See note 2

NC

1. Connect cable screen toenclosure cable gland.

S2:5

S1:10

S1:9

S1:810V+

+ 10V+

S2:6

S2:7

S2:8

S2:9

S2:10

4. Switches shown in default positions.

S2:1 & S2:2

39R S1:3

S1:4

S1:5

S1:6

S1:7

200R

100R

51R

33R

20R

10K

S1:1 & S1:2S2:3 & S2:4

+

is 500mA. It cannot power a DDV.

resistors on P.C.B. to select mfbinput current. Default 390K.

BLOCK WIRING DIAGRAM

SPECIFICATIONS

ORDERING INFORMATIONBuffer Amplifier G123-825-001 Delivery includes Buffer Amp, DIN fuse holder,

2 x M205 250 mA T fuses and a 4 page application note.

Signal input 4 to 20 mA0 to ±100 mA0 to ±10 V

Current signal input Terminals 4 to 8. 50 Ohm

Voltage signal input Terminal 3. 100 k Ohm or 1 k Ohm with low Rin selected.

Valve drive outputs 0 to ±10 V @ 1 k Ohm min load4 to 20 mA @ 500 Ohm max load0 to ±100 mA max

max load = ( 11 V –39) Ohm I (Amp)where I is valve current switch selection in Amps.

Valve drive current selections

±5, 10, 20, 30 & 50 mA

Valve drive test point Zo = 10 k Ohm

Vv LED Maximum illumination at ±10 V.+ = red– = green

Iv LED Maximum illumination at ±5 mA to ±100 mA.+ = red– = green

Vs LED Internal supply, OK = green

Valve filter type Active, single pole

Valve filter corner frequency selections

7, 16, 34, 72 & 723 Hz, ±10%

Supply Terminal 124 V nominal, 22 to 28 V65 mA @ 24 V, no output current170 mA @ 100 mA output current

Recommended supply protection

M205, 250 mA T (slow blow) fuse compliant with IEC 127-2 sheet 3.

±15 V output Terminals 12 and 16, ± (110 mA – max valve current)

Terminal 10 max current

500 mA. If terminal 10 is used to power a proportional valve, the terminal 1 supply fuse should be increased to cater for the extra current.

Mounting DIN rail

Class of protection IP 20

Temperature 0 to 40°C (32 to 104ºF)

Dimensions 100 mm (4 ins.) W108 mm (4 1/4 ins.) H22.5 mm (7/8 ins.) D

Weight 120 g (4.2 oz.)

CE mark EN50081.1 emissionEN50082.2 immunity

C tick AS4251.1 emission