Moog G122-829-003 User manual

1 Scope
These Application Notes are a guide to applying the
G122-829-003 P-IServoamplifier. These Application Notes
can be used to:
Determine the closed loop structure for your application.
Select the G122-829-003 for your application. Refer also
to data sheet G122-829.
Use these Application Notes to determine your system
configuration.
Draw your wiring diagram.
Install and commission your system.
Aspects, such as hydraulic design, actuator selection, feedback
transducer selection, performance estimation, etc. are not
covered by these Application Notes. The G122-202 Application
Notes (part no C31015) cover some of these aspects. Moog
Application Engineers can provide more detailed assistance,
if required.
2 Description
The G122-829-003 is a general purpose, user configurable,
P-Iservoamplifier. Selector switches inside the amplifier enable
either proportional control, integral control, or both to be
selected. Many aspects of the amplifier’s characteristics can be
adjusted with front panel pots or selected with internal
switches. This enables one amplifier to be used in many
different applications. The output amplifier is fixed at 4-20mA.
Refer also to data sheet G122-829.
3 Installation
3.1 Placement
A horizontal DIN rail, mounted on the vertical rear surface
of an industrial steel enclosure, is the intended method of
mounting. The rail release clip of the G122-829-003 should
face down, so the front panel and terminal identifications
are readable and so the internal electronics receive a cooling
airflow.
An important consideration for the placement of the module is
electro magnetic interference (EMI) from other equipment in
the enclosure. For instance, VF and AC servo drives can
produce high levels of EMI. Always check the EMC compliance
of other equipment before placing the G122-829-003 close by.
3.2 Cooling
Vents in the top and bottom sides of the G122-829-003 case
provide cooling for the electronics inside. These vents should
be left clear. It is important to ensure that equipment below
does not produce hot exhaust air that heats up the G122-829.
P-IServoamplifier
G122-829-003
MOOG
1
2
34
9101112
56
7
8
13 14 15 16
32313029
24
2
3
2221
28272625
20191
8
17
f
eedback
valve
e
n
ab
l
e
dither
V
s
in posn.
P
I
inp.1
sca
l
e
g
ai
n
g
ai
n
b
i
as
c
ontroll
er
gain
zero
Bottom
vents
Cooling
airflow
release
Screw
terminals
Top vents
Screw
terminals
DIN r
a
i
l
17 - 32
1 - 16
clip
Cover
release
tab (4)
DIN rail
Application Notes
Page 1 of 6: C70916 Rev B –4.10

3.3 Wiring
The use of crimp “boot lace ferrules”is recommended for the
screw terminals. Allow sufficient cable length so the circuit
card can be withdrawn from its case with the wires still
connected. This enables switch changes on the circuit card
to be made while the card is still connected and operating.
An extra 100mm, for cables going outside the enclosure,
as well as wires connecting to adjacent DIN rail units,
is adequate.
The screw terminals will accommodate wire sizes from 0.2mm2
to 2.5mm2(24AWG to 12AWG). One Amp rated, 0.2mm2
should be adequate for all applications.
cable gland
100mm Loop
WiresEnclosure
Radial screen
termination
Cable
Grounded EMI
Preferred Wiring
Page 2 of 6: C70916 Rev B –4.10
Cable gland
100mm Loop
CableEnclosure
Cable
Wire soldered
to screen
Drain wire.
or
(Heat shrink to
cover the screen)
Alternative Wiring
3.4 EMC
The G122-829-003 emits radiation well below the level called
for in its CE mark test. Therefore, no special precautions are
required for suppression of emissions. However, immunity from
external interfering radiation is dependent on careful wiring
techniques. The accepted method is to use screened cables for
all connections and to radially terminate the cable screens, in
an appropriate grounded cable gland, at the point of entry into
the industrial steel enclosure. If this is not possible, chassis
ground screw terminals are provided on the G122-829-003.
Exposed wires should be kept to a minimum length. Connect
the screens at both ends of the cable to chassis ground.
4 Power supply
24V DC nominal, 22 to 28V
75mA @ 24V without a load, 200mA @ 100mA load.
If an unregulated supply is used the bottom of the ripple
waveform is not to fall below 22V.
It is recommended that an M205, 250mA T (slow blow) fuse,
compliant with IEC127-2 sheet 3, be placed in series with the
+24V input to protect the electronic circuit. If terminal 23 is
used to power a proportional valve, the fuse should be
increased to cater for the extra current.
R17
1
2
3
4
spare
enable
dither
4-20mA (feedback input)
P gain range
Input 3 to
output amplim
cmd lag
feedback lead
Input 2 to
error amp
R34
R33
R16
SW5
SW4 SW 6
1
2
3
4
spare
PR
INT
EorP
SW5 V or
SW 3
Step P.B.
[SW1]
To access the circuit card switches, the circuit card must be
withdrawn from the case. See paragraph 17.
5 Set-up adjustments
Trimpots are all 15 turns.
Plug-in resistors are all “quarter watt”1% metal film. Two
suitable types are Beyschlag MBB0207 and Roderstein
MK20207.
The amplifier is shipped in the following default state.
top board switches
SW3 STEP not applicable
SW4 1 P-E E
2 CMD LAG off
SW5 IN 2 V
SW6 1 spare off
2PR on
3ILim off
4 INT off
bottom board switch, shown as [ ]
[SW1] 1 spare off
2 ENABLE on
3 DITHER off
4 4-20mA (fdbk) on
R17: 100k (P gain range 1 to 20)
R34: 100k (input 2 to error amp)
R33: not fitted (input 3 to output amp)
R16: not fitted (feedback derivative)
Feedback gain and zero pots: configured for 4-20mA input
Dither level pot: fully counter clockwise (FCCW)
Scale pot: FCCW
P gain pot: FCCW
Igain pot: FCCW
Bias pot: 0V
ON
shown in on position
shown in off position
SW1 and 6 switch positions

Adjust the feedback gain trimpot until the DMM reads
-10.00V.
Set the variable supply to 0.96V again and check the
feedback test point is still 0.00V. Trim if necessary and check
the 4.80V setting again.
6.2 Input 1
An input to the error amplifier: This input is ±10V
non-inverting and has two important features:
It has a scale pot on its input that enables large inputs to be
scaled down to match smaller signals on other inputs. Scale
range is 10 to 100%. Set fully clockwise (FCW), an input of
100V can match a 10V signal on the other inputs. Note that
the maximum permissable input voltage is ±95V.
It has a switch selectable lag (SW4:2) of 55mS that can be
used to remove transients from the input signal that could
cause unwanted rapid movement in the output.
Input 1 is well suited to be a command because of these two
features. If input 1 is used for feedback, be sure the lag is
switched off. Input resistance after the scale pot is 94k Ohms.
6.3 Input 2
An input to the error amplifier: This input is non-inverting. It is
switch selectable (SW5) between 4-20mA and ±10V. The
4-20mA converter produces 0 to +10V for 4 to 20mA input.
R34 connects from the output of the converter to the input of
the servo amp when 4-20mA is selected. Plug-in input resistor
R34, of 100k Ohms, gives a nominal 0 to 10V input signal
range when V rather than 4-20mA is selected. Input 2 is
suitable for command or feedback. R34 can be increased to
give a larger input range.
6.4 Input 3
An input to the output summing and limiting amplifier via a
plug-in resistor, R33. A typical use for this input is command
feed forward. With R33 at 10k Ohm, a ±10V input will produce
±100% valve drive. Increasing R33 reduces the valve drive.
7 Output configuration
The output signal is 4-20mA. No other signal type can be
selected. Permissable load range is 0 Ohm to 500 Ohm.
Nominal null output is 12mA.
The output amplifier is limited to approximately 105% of the
selected full scale output. If both the proportional and
integrator stages are saturated, the output will not be twice
the selected full scale but still only 105% of full scale.
8 Step push button
The step push button (SW3) injects -50% valve drive
disturbance into the output. When released, the valve drive
reverts to its original level. This feature is useful for closed loop
gain optimisation.
9P-Iselection
For position closed loops, initially select only P (SW6:2).
For pressure or velocity loops select I(SW6:4) initially and
then P. See paragraph 12 below for more detail. For a
complete discussion of P and Icontrol, see the G122-202
servoamplifier Application Notes (part no C31015).
Page 3 of 6: C70916 Rev B –4.10
Caution
If you intend to use the feedback amplifier adjusted for
4-20mA, don’t change the feedback gain or zero.
They are already adjusted for 4-20mA
To re-adjust for 4-20mA takes a little time, needs test
equipment and is tedious to do in the field.
6 Input configuration
Inputs 1, 2 and feedback go to the error amplifier and can be
used for feedback or command. Care needs to be taken in
selecting signal polarity to achieve negative feedback for
the overall closed loop. Since the input error amplifier sums
the signals, the transducer feedback signal needs to be the
opposite polarity of the command. This can be achieved in
two ways:
Arrange for an opposite polarity feedback transducer signal
and connect it to input 1, input 2 or the positive feedback
amplifier input.
If the feedback transducer signal is the same polarity as the
command, you only have one option: Connect it to the
negative input of the feedback amplifier.
6.1 Feedback input
An input to the error amplifier: The feedback amplifier is the
best choice for the feedback signal, for six reasons:
It leaves input 1 available for command. See 6.2 below.
It has inverting (negative) and non-inverting (positive) inputs.
It has zero and gain adjustment pots. This enables a signal
that does not go to zero volts and has less span than the
command, to be scaled up to the command. While this is
not essential, it helps when setting up and trouble-shooting.
There is a front panel test point for the zeroed and amplified
signal. This is very convenient (essential) for setting up and
trouble-shooting.
 There is the option of a plug-in resistor, R16, to give a
feedback
derivative (lead or D) in the output of the feedback
amplifier.
 It can be set up for a current input by connecting a 240 Ohm
resistor between terminals 17 and 18 with the 4-20mA
switch ([SW1:4])
.
Default
The feedback amplifier default set-up is 4-20mA flowing into
terminal 18 and out of terminal 17, producing an output of
0 to -10V. Reversing the terminals, and hence the current flow,
will not result in a 0 to +10V output. The feedback zero must
be adjusted for this arrangement.
Adjusting feedback amp for 4-20mA input and
0 to -10V output
Set the feedback gain to minimum (fully counter clockwise).
The trimpot has 15 turns and will click when minimum is
reached.
Connect terminal 17 to terminal 26 (ground).
Connect the positive of a variable DC power supply to
terminal 18 and the negative to terminal 26.
Connect a digital multimeter (DMM), on DC Volts, between
the front panel feedback amp and ground test points.
Set the variable supply to 0.96V.
Adjust the feedback amp zero trimpot until the DMM reads
0.00V.
Set the variable supply to 4.80V.

10 Integrator input
The servoamplifier has a unity gain input error amplifier
followed by two parallel stages, one a proportional amplifier
and the other an integrator. The outputs of these two stages
can be switched to the output power amplifier (see paragraph
7 above) which then drives the valve.
The input to the integrator stage can be switch selected
(SW4:1) from either the output of the error amplifier, Iin = E,
or the output of the proportional stage, Iin = P. The latter
arrangement is used in the G122-202. It is beyond the scope
of these Application Notes to detail the benefits of each
arrangement. If you have experience with the G122-202,
Iin = P would seem to be an easy choice.
11 P only gain
For position loops select only P control (SW6:2). Input a step
disturbance of 50% valve current with the step push button
(SW3). Adjust the P gain for the required stability, while
monitoring the front panel valve test point, or the feedback
signal. The gain range of the proportional amplifier can be
moved by changing the plug-in resistor R17. The value loaded
when shipped is 100k Ohms, which gives a 1 to 20 range.
Selecting 200k Ohms will give 2 to 40. The circuit will function
correctly with the value of R17 between 100k Ohms and 10M
Ohms.
Note that as P gain is increased, the movement due to the step
push button decreases.
12 P and Igains together
If you are inexperienced with integral control the following
set-up method is a good starting point.
Iin = E: Initially select only I(SW6:4). Press the step push
button (SW3). Increase Igain until one overshoot in the
feedback signal is observed.
Next select P (SW6:2) and I(SW6:4) together and increase the
P gain to reduce the overshoot.
For the Iin = E arrangement the P and Isequence could be
reversed. i.e.: adjust P first, followed by I.
Iin = P: For an Iin = P arrangement, only the “P followed
by I”sequence of adjustment can be used.
For a more thorough discussion see G122-202 Application
Notes (part no C31015).
13 Ilimit
The contribution from the integrator to the output amplifier
can be reduced by selecting Ilimit on (SW6:3). When this
switch is on the integrator contribution is reduced to
approximately 15% of the level when it is off. This feature is
useful in a position loop that may require integral control to
achieve the required steady state accuracy. The limited integral
control removes valve null error when the final position is
reached. It is also useful in a pressure loop to limit overshoot,
if the valve drive saturates.
14 Dither
The dither frequency is fixed at 200Hz and the level is
adjustable with the front panel pot to ±10% of valve drive,
regardless of the type and level of valve drive selected. It can
be turned on or off with ([SW1:3]). Dither is seldom needed in
a position loop but can be beneficial in pressure or velocity
loops. Increase dither until it can just be detected in the
controlled variable, such as pressure or velocity. Dither can
compromise valve life, so it should be kept to a minimum.
15 Enable
A relay on the circuit card needs to be energised to connect
the output stage to its screw terminal and to un-clamp the
integrator. The clamp prevents integrator wind-up when the
loop is not operating. Supply 24V to the appropriate terminal
to energise the relay. The enable switch ([SW1:2]) on the circuit
card can be set to permanently energise the relay and provide
a permanent enable.
16 In position
When the valve drive signal falls below ±10% of full scale
signal, the “in position”signal goes true and provides an
opto-isolated current path between the + and –terminals.
This can be connected to a PLC to initiate the next step in
a control sequence. Do not apply more than 40V to the
+ terminal and ensure the load on the –terminal is less
than 20mA.
The “in position”signal is not relevant for a velocity loop.
17 Withdrawing the circuit card
from its case
The circuit card needs to be withdrawn from its case to set the
selector switches, change the plug-in resistors and operate the
step push button.
To do this, push one cover release tab with a pen or
screwdriver, while gently pulling on the top cover on that side.
The cover will release approximately one mm. Repeat on the
second tab on that side. Repeat on the other side and then
withdraw the cover and circuit card until the required switches
are exposed. The rigidity of the connecting wires will hold the
circuit card in position while changes are made.
Page 4 of 6: C70916 Rev B –4.10

Page 5 of 6: C70916 Rev B –4.10
18 Specifications
Function: P, I, or P & I, switch selectable
Input 1: Scaled to 95V max with switch
selectable lag of 55mS.
Input 2: Switch selectable.
4-20mA 240R load, for 0 to +10V on R34.
Or 0 to ±10V direct onto R34.
R34 is plug-in, 100K nominal.
Input 3: R33 plug-in. ±10V gives ±100% valve
drive when R33 = 10k Ohm, ±10% when
R33 = 100k Ohm.
Feedback input: Differential 4-20mA or ±10V, switch
selectable
±15V max.
R in 100k –±10V
R in 240R –4-20mA
Feedback amp: Zero, ±10V.
Gain, 1 to 10.
Derivative (velocity) feedback via
plug-in resistor R16 and fixed capacitor.
Transducer excitation: +10V @ 10mA max.
Error amp: Unity gain.
Bias ±1.5V.
Proportional amp gain: 1 to 20.
Integrator gain: 1 to 45 per second.
Integrator input: Switch selectable from output of unity
gain error amp or proportional gain amp
Enable: Relay, +24V @ 8mA, 17 to 32V.
Output amp: Fixed at 4-20mA. Nominal null output is
12mA. Permissable load range is 0 Ohm to
500 Ohm.
Step push button: -50% valve drive disturbance.
Valve supply: Terminal 23, 300mA max.
In position: ±10% of valve drive. 20mA and 40V max
output to PLC.
Front panel Vs, internal supply –green
indicators: Valve drive positive –red
negative –green
Enable –yellow
In position –green
Front panel Valve: 2 to 10V for 4-20mA
test points: Feedback amplifier output
signal 0V
Front panel Input 1 scale
trimpots: Error amp bias
(15 turns) P gain
Igain
Dither level
Feedback amp gain
Feedback amp zero
Dither: 200 Hz fixed frequency.
±10% valve drive. Switch selectable
on/off
Supply: Terminal 1,
24V nominal, 22 to 28V
75mA @ 24V, no valve current,
200mA @ 100mA valve current
±15V output: Terminals 14 and 15,
± (110mA –max valve current)
Wire size range: 0.2mm2to 2.5mm2
(24AWG to 12AWG)
Recommended M205, 250mA T (slow blow) fuse
supply protection: compliant to IEC127-2 sheet 3.
If terminal 23 is used to power a
proportional valve, the fuse should be
increased to cater for the extra current.
Mounting: DIN rail
IP 20
Temperature: 0 to +40ºC
Dimensions: 100W x 108H x 45D
Weight: 180g
CE mark: EN50081.1 emission
EN61000-6-2 immunity
C tick: AS4251.1 emission
19 Internet
www.moog.com/dinmodules

Industrial Controls Division. Moog Inc., East Aurora, NY 14052-0018. Telephone: [phone]. Fax: [phone]. Toll Free 1-800-272-MOOG.
Moog GmbH. Germany. Telephone: [phone]. Fax: [phone].
Moog Sarl. France. Telephone: [phone]. Fax: [phone].
Moog Australia Pty. Ltd. Telephone: [phone]. Fax: [phone].
Moog pursues a policy of continuous development and reserves the right to alter designs and specifications without prior notice. Information contained herein is for guidance only and does not form part of a contract.
Australia: Melbourne, Sydney, Brisbane Austria: Vienna Brazil: S~
ao Paulo Denmark: Birkerød England: Tewkesbury Finland: Espoo France: Rungis Germany: Böblingen, Dusseldorf Hong Kong: Shatin India: Bangalore
Ireland: Ringaskiddy Italy: Malnate (VA) Japan: Hiratsuka Korea: Kwangju-Kun Philippines: Baguio City Singapore: Singapore Sweden: Askim USA: East Aurora (NY)
20 Block-wiring diagram
Page 6 of 6: C70916 Rev B –4.10
+15V -15V
TP
Power Supply
1 2
Output Amp
TP
valve
11
LED
valve
LEDVs
bias
7 8
100K
6 5
10K
47K 47K
26
17 18
4-20mA
100K
feedback lead
Feedback Amp
TP
feedback
gain
zero
20 19
Transducer Excitation
+
dither
Dither
Oscillator
dither
Error Amp
Av=1
Pgai
n
LED
enable
EP
gain
PGainAmp
Integrator
INT PR
In Position Comparator
12
3 4 31 32 22
23 24
100R
scale
Integrator input
select
cmd lag
N.F.
R16 N.F.
R17
100K
R34
9
+24V
0V
Supply
16
signal 0Vref
Input 2
13
signal 0Vref
Input 1
27
+10V
0V
Typical
Feedback Input
see note 1 see note 1 see note 1
see note 1
+
see note 1
PLC +24V Enable +24V In position
see note 1
13 10
B D E
F
A
efb Valve Typical D66X Prop. valve spool see note 2 mfb Valve Connect to
Note: 1. Connect cable screen to enclosure cable gland
or chassis ground terminal on G122-829-003.
+24V
25
0Vref
1K
+24V +24V
14
+15V
15
-15V
28
lim
2.2uF
+10V
+
Note: 2. Connect spool (pin F) to terminal 22,
only if the spool signal is a current.
pins 31 & 32.
+
+
4-20mA
-50%
Step P.B.
R33
+24Venable
Converter
240R
100K 100K
100K 100K
125R39R
Note: 3. Switches shown in default shipping mode.
240R
linear pot feedback
21
V
V
Input 3
Sum & Limit
Amp
signal
250mA
Tfus
e
+
-
+
SW5
SW5
SW3
Note: 4. [ ] indicates bottom board.
[SW1:2]
SW6:4
SW6:2
SW6:3
[SW1:3]
SW4:2
SW4:1
[SW1:4]