Copley Controls Corp. 300 Series User manual

1996~1998 Copley Controls Corporation
20 Dan Raod
Canton, MA 02021
USA
All rights reserved
The 300 Series Amplifier User' s Guide Rev 09 12/01/01
300 Series Amplifier
User’s Guide

300 SERIES USER GUIDE
ii
Table of Contents
Table of Contents.......................................................................................................................................ii
A Visual Guide to the 300 family:..............................................................................................................iv
Introduction................................................................................................................................................1
Getting Started ...........................................................................................................................................1
Functional Diagram....................................................................................................................................2
J17 Component Header..............................................................................................................................3
Location.......................................................................................................................................3
Current-Mode Setup (Standard configuration).............................................................................3
Velocity Mode Setup (Use components supplied).......................................................................3
Technical Specifications ............................................................................................................................4
Mechanical Outlines...................................................................................................................................5
Basic Amplifier Connectors, Signals and Pinouts......................................................................................6
4 Pin power connector .................................................................................................................6
22 Pin signal connector................................................................................................................6
Basic Amplifier: Current-Mode, NO Tachometer......................................................................................7
Amplifier Connections.................................................................................................................7
Basic Amplifier: Current-Mode WITH Tachometer..................................................................................8
Amplifier Connections.................................................................................................................8
Amplifier with MB4 Mounting Card: Current-Mode, NO Tachometer .....................................................9
Amplifier Connections.................................................................................................................9
Amplifier with MB4 Mounting Card: Current-Mode, WITH Tachometer................................................10
Amplifier Connections.................................................................................................................10
Amplifier on Eurocard: Current-Mode, NO Tachometer...........................................................................11
Amplifier Connections.................................................................................................................11
Amplifier on Eurocard: Current-Mode, WITH Tachometer ......................................................................12
Amplifier Connections.................................................................................................................12
Power Supply Considerations.....................................................................................................................13
Multiple Amplifier Power Connections .......................................................................................13
Minimum Inductance..................................................................................................................................14
Maximum Inductance.................................................................................................................................14
Bandwidth..................................................................................................................................................14
Enable Inputs..............................................................................................................................................15
Current Monitor .........................................................................................................................................15
Status LED.................................................................................................................................................15
Normal Output ...........................................................................................................................................16
Reset Input .................................................................................................................................................16
Current Limit..............................................................................................................................................16
Output Voltage Swing................................................................................................................................16
DC Power Outputs .....................................................................................................................................17
Mounting....................................................................................................................................................18
Standard Mounting.......................................................................................................................18
PC Board Mounting (-P option)...................................................................................................18
MB4 Card Mounting ( -M option)...............................................................................................18
Eurocard Mounting (-E and -ER options)....................................................................................18
MB4 Mounting Card..................................................................................................................................19
Notes on Nomenclature................................................................................................................19
P1: 4 Pin power connector...........................................................................................................19
P2: 15 Pin signal connector..........................................................................................................19
Status Output................................................................................................................................19
Amplifier Signal Connector (J4)..................................................................................................19
MB4 Card Options.......................................................................................................................20
Voltage-Mode (-V option).............................................................................................20
IR-Comp (included with -V option)...............................................................................20
PWM Inputs (-D option)................................................................................................20
Edge filters (-F option) ..................................................................................................20
MB4 Card Jumper Settings..........................................................................................................21

300 SERIES USER GUIDE
iii
Notes on Modes & Jumpers...........................................................................................21
Eurocard Mount..........................................................................................................................................22
DIN Connector Pinouts................................................................................................................22
Jumper Settings............................................................................................................................22
Status Output Jumper ...................................................................................................................23
Tuning and Adjustments.............................................................................................................................23
Trimpots.......................................................................................................................................23
Balance ..........................................................................................................................23
Feedback........................................................................................................................23
Current Limit .................................................................................................................23
Voltage Feedback ..........................................................................................................23
IR Comp.........................................................................................................................23
Mode Setting: Flat-Gain vs. Tachometer .....................................................................................24
Frequency Response with Tachometer.........................................................................................25
Tachometer Scaling......................................................................................................................26
Voltage-Mode Gain......................................................................................................................27
IR-Comp.......................................................................................................................................28
Setup Procedure.............................................................................................................28
Static Setup Method.......................................................................................................28
Dynamic Setup Method..................................................................................................29
Notes on IR Compensation ............................................................................................29
PWM Operation...........................................................................................................................30
Appendix....................................................................................................................................................31
Connector Part Numbers..............................................................................................................31
Basic Amplifier 4-pin power/motor connector ................................................31
Basic Amplifier 22-pin signal connector (housing only).................................31
MB4 Card: 4 pin power/motor connector........................................................31
MB4 Card: 15 pin signal connector (housing only).........................................31
Pins for 15, 22 pin signal connector ................................................................31
DIN backplane connector for Eurocard mount................................................31
References....................................................................................................................................31
Standard Power Supplies.............................................................................................................31
MB4 Card Layout ........................................................................................................................32
Eurocard Layout...........................................................................................................................33
Jumper Pin Numbering ..................................................................................................33
Panel Layout ..................................................................................................................33
MB4 Card Schematic...................................................................................................................34
Eurocard Schematic......................................................................................................................35
Ordering Guide for 300 Series.....................................................................................................36

300 SERIES USER GUIDE
iv
A Visual Guide to the 300 family:
Basic Amplifier, No Mounting Card, No Heatsink (30x shown)
See p. 5 for connectors & pinouts.
See pp. 7-8 for wiring.
Amplifier with MB4 Mounting Card (30xPMFDV shown)
See p. 18 for connectors & pinouts.
See pp. 9-10 for wiring.
Amplifier on Eurocard Mount with Front Panel (30xER shown)
See p. 21 for connectors & pinouts.
See. pp. 11-12 for wiring.

300 SERIES USER GUIDE
1
Introduction
The 300 Series amplifiers are second generation products designed for low cost and high
performance. They can be mounted on chassis or p.c. boards and operate from 16 to 160
volt single-output DC power supplies. A wide range of inductive loads can be driven:
64 uH to 50 mH depending on model and supply voltage.
All units feature fully differential inputs for the control, or reference voltage. Enable
inputs for output control, a status output, and a current monitor signal ease system
interfacing.
The 22 kHz. PWM switching frequency eliminates audible noise from motor windings
and fast rise and fall times give high efficiency.
A Eurocard mount is available for 3U x 220 mm. rack mounting applications. A header
socket with plug-in components makes it easy to change compensation components for
different loads.
The amplifier is protected against over-temperature, over-voltage and under-voltage, and
output short circuits.
Getting Started
To install the amplifier you will need a control, or reference voltage, a power supply, and
a load. The reference voltage can be from something as simple as a potentiometer, or as
complex as a digital control system. The power supply can be supplied by the user, or
ordered from Copley Controls along with the amplifier to create a complete amplifier
subsystem. Loads are usually motors, but magnet coils, inductors, or other non-motor
loads can also be driven.
The amplifier is typically used as a voltage-to-current converter. ±10V reference signals
will drive the amplifier's peak rated current to the load in the 'flat-gain' mode. If a
tachometer is used, the amplifier is still operated as a voltage to current converter, but
the header components are changed to increase the gain of the servo preamplifier.
Use of the MB4 and Eurocard provides additional (optional) features such as voltage-
mode operation, armature-resistance(IR) compensation, PWM inputs, and output filters.
Eurocard mounts adapt the amplifiers to 3U subrack installations. Consult the factory for
Eurocard subrack systems.

300 SERIES USER GUIDE
3
J17 Component Header
This is an 11-position socket which holds resistors and capacitors which are used for
tachometer scaling and compensation, amplifier compensation, and current limiting.
Location
Current-Mode Setup (Standard configuration)
This is the standard configuration as delivered from the factory. In this mode, a voltage
at the reference inputs will force a current at the amplifier outputs. This is also called the
flat-gain mode because it provides the maximum bandwidth which remains constant over
the 3 kHz range.
Velocity Mode Setup (Use components supplied)
Use the components supplied in the brown bag to replace R5,R7, and C6. This will setup
the amplifier for use with tachometers. See Mode Setting for further details.
4-PIN
22-PIN
J17 HEADER
AMPLIFIER WITHOUT MB4 CARD
1
2
3
4
5
6
7
8
9
10
11
22
21
20
19
18
17
16
15
14
13
12
R1
R2
C3
C4
R5
C6
R7
R8
JP9
R10
R11
10 K
Value
Component
40.2 K
OPEN
330 pF
46.4 K
.01 uF
JUMPER
10 K
JUMPER
49.9 K
49.9 K
Current Limit ; 10K = 100% of peak rated current
Enable polarity ; IN = Enable, OUT = Enable
Aux Input Gain
Ref Gain ; amplifier gain = Ipeak/10V
Function as Shown
Notes:1. R1, R2, C3 and C6 have no function in current mode.
2. Current-limiting is non-linear with respect to R8. For best results, substitute 10K pot
for R8, adjust for desired current-limit, and replace with fixed resistor.
Not used in current-mode
Flat gain
1
2
3
4
5
6
7
8
9
10
11
22
21
20
19
18
17
16
15
14
13
12
R1
R2
C3
C4
R5
C6
R7
R8
JP9
R10
R11
10 K
Value
Component
40.2 K
OPEN
330 pF
499 K
.01 uF
10 MEG
10 K
JUMPER
49.9 K
49.9 K
Tach scaling ; 10V @ Ref = 8V @ Tach
Compensation (see Mode Setting section, p. 23)
Current Limit ; 10K = 100% of peak rated current
Enable polarity ; IN = Enable, OUT = Enable
Aux Input
Ref Gain ; servo preamp DC gain = 210
Function as Shown
Notes:
1. R1, R2, and R11 interract to affect tachometer scaling and servo preamp gain.
2. Current-limiting is non-linear with respect to R8. For best results, substitute 10K pot
for R8, adjust for desired current-limit, and replace with fixed resistor.
(see Note 1 and Tachometer Scaling, p. 25)

300 SERIES USER GUIDE
6
Basic AmplifierConnectors, Signals and Pinouts
If you are using the MB4 or Eurocard, the pinouts will be different (refer to the sections
on the MB4 and Eurocard). Use this list when reading the following sections on hooking
up the basic amplifier.
Types of signals are listed after the pin number or letter.
P Passive Power and ground
I Input Analog or digital signal inputs
O Output Signal, logic, and power-stage outputs
Note: See appendix for complete listing of connectors and part-numbers.
4 Pin power connector
Type Remarks
AA P +HV, the high-voltage DC power input
BB O Out- , or negative output
CC O Out+, or positive output
DD P Ground and +HV power return
Table 1
22 Pin signal connector
Note that pins are referred to by letter and number. The letter refers to the functional
schematic. The number is the actual connector-pin number on the cable header that
connects to the amplifier.
-Pin- Type Signal Remarks
1 (A) I +Ref Differential (+) reference signal input
2 (B) I -Ref " (-) " " "
3 (C) P Signal Gnd Gnd for tachometer, signal gnd
4 (D) O Ref amp out Output of differential input amplifier
5 (E) I Aux input Auxiliary input
6 (F) O +11V 20K ohms in series with +11V
7 (G) P Logic gnd Gnd for Enable inputs
8 (H) O -11V 20K ohms in series with -11V
9 (I) N.C. No connection to this pin
10 (J) I /Reset LO or Gnd to reset fault condition
11 (K) O Preamp out See schematic
12 (L) Opt. ext. comp See schematic
13 (M) I Tach input Tachometer input
14 (N) Opt. ext. comp See schematic
15 (O) I /Enable LO or Gnd to enable amplifier
16 (P) I /Pos Enable LO or Gnd to enable positive output
17 (Q) I /Neg Enable LO or Gnd to enable negative output
18 (R) O +14V 1K ohms in series with +14V
19 (S) O Normal HI (+5V) when amplifier operating Normally
20 (T) O +5V 2.49K in series with internal +5V
21 (U) N.C.
22 (V) O Current monitor Outputs +/-6V at amplifier peak current
Table 2

300 SERIES USER GUIDE
7
Basic Amplifier: Current-Mode, NO Tachometer
Use this checklist for applications that don't employ a tachometer. These include
microprocessor control systems that get position feedback from an encoder on the
motor, as well as non-motor applications such as magnet-coil, solenoids, or other loads
that require a set current from the amplifier in response to a control-voltage at the
inputs. The components on the J17 header come from the factory preset for this
operating mode. See functional diagram on page 2.
1. Connect DC power supply to amplifier +HV and GND. Check voltage to see that is is
within the amplifiers' rating.
2. Ground amplifier to chassis at GND pin DD.
3. Connect motor or load between OUT+ and OUT-. Do not ground load!
4. Connect reference voltage source to REF+ and REF- inputs.
5. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
6. Set FEEDBACK pot to full CW.
7. Set Vref to 0V
8.Turn power on
9.Check for green LED indicating Normal operation.
10. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
11. Momentarily increase Reference voltage (±10V max).
12. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
13. Set Reference voltage to maximum value (+/-10V)
14. Check load current at CURRENT MONITOR output
15. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for
best response with no oscillation.
Amplifier Connections
Numbered terminals are on the brown 22-pin connector. Double-letter terminals are on
the orange 4-pin connector. See appendix for connector part numbers.
15
16
17
7
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
AA
DD
CHASSIS GND
1
2
AMPLIFIER
BB
CC
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
CONTROLLER
OUT
GND
POWER
SUPPLY
22-Pin 4-Pin
Fig. 1

300 SERIES USER GUIDE
8
Basic Amplifier:Current-Mode WITH Tachometer
1.Setup J17 header components for high gain, tachometer mode (see p.3)
2. Connect DC power supply to amplifier +HV and GND. Check voltage to see that is
within the amplifiers' rating.
3.Ground amplifier to chassis at GND pin DD.
4.Connect motor or load between OUT+ and OUT-. Do not ground load!
5. Connect reference voltage source to REF+ and REF- inputs.
6. Connect Tachometer between tach input and signal ground.
7. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
8. Set FEEDBACK pot to full CW.
9. Set VREF to 0V
10. Turn power on.
11. Does the motor run away?:
YES: remove power, reverse tachometer leads
NO: continue
12. Check for green LED indicating Normal operation.
13. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
14. Momentarily increase Reference voltage (±10V max).
15. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
16. Set Reference voltage to maximum value (+/-10V)
17. Check load current at CURRENT MONITOR output
18. Adjust CURRENT LIMIT trimpot for desired maximum current.
19. Set Reference voltage to zero, turn feedback trimpot CCW until oscillation begins
(audible squeal or noise). Back-off two turns CW or until oscillation stops.
20. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for best
response with no oscillation.
Amplifier Connections
Single-letter terminals are on the brown 22-pin connector. Double-letter terminals are on
the orange 4-pin connector.
15
16
17
7
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
AA
DD
CHASSIS GND
1
2
AMPLIFIER
BB
CC
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
13
3
TACH +
-
+
-
CONTROLLER
POWER
SUPPLY
22-Pin 4-Pin
Fig. 2

300 SERIES USER GUIDE
9
Amplifier with MB4 Mounting Card: Current-Mode, NO Tachometer
Use this checklist for applications that don't employ a tachometer. These include
microprocessor control systems that get position feedback from an encoder on the
motor, as well as non-motor applications such as magnet-coil, solenoids, or other loads
that require a set current from the amplifier in response to a control-voltage at the
inputs. The components on the J17 header come from the factory preset for this
operating mode. See functional diagram on page 2.
1. Connect DC power supply to MB4 card P1 (see diagram below). Check voltage to
see that is is within the amplifiers' rating.
2. Ground MB4 card to chassis at pin P1-4.
3. Connect motor or load between OUT+ and OUT-. Do not ground load!
4. Connect reference voltage source to REF+ and REF- inputs.
5. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
6. Set REF GAIN pot to full CW.
7. Set FEEDBACK pot to full CW.
8. Set CURRENT LIMIT pot to full CW.
9. Set Vref to 0V
10. Turn power on
11. Check for green LED indicating Normal operation.
12. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
13. Momentarily increase Reference voltage (±10V max).
14. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
15. Set Reference voltage to maximum value (+/-10V)
16. Check load current at CURRENT MONITOR output
17. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for best
response with no oscillation.
Amplifier Connections
Numbered terminals are on the brown 15-pin connector(P2). Double-letter terminals are
on the orange 4-pin connector(P1). See appendix for connector part numbers.
3
2
1
11
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
1
4
CHASSIS GND
8
15
2
3
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
CONTROLLER
OUT
GND
POWER
SUPPLY
P1
P2
MB4 Card
Fig. 3

300 SERIES USER GUIDE
10
Amplifier with MB4 Mounting Card: Current-Mode,
WITHTachometer
Use this checklist for applications that do employ a tachometer. These include
microprocessor control systems that get position feedback from an encoder on the
motor, as well as non-motor applications such as magnet-coil, solenoids, or other loads
that require a set current from the amplifier in response to a control-voltage at the
inputs. The components on the J17 header come from the factory preset for this
operating mode. See functional diagram on page 2.
1. Connect DC power supply to MB4 card P1 (see diagram below). Check voltage to
see that is is within the amplifiers' rating.
2. Ground amplifier to chassis at pin P1-4.
3. Connect motor or load between OUT+ and OUT-. Do not ground load!
4. Connect reference voltage source to REF+ and REF- inputs.
5. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
6. Set REF GAIN pot to full CW.
7. Set FEEDBACK pot to full CW.
8. Set CURRENT LIMIT pot to full CW.
9. Set Vref to 0V
10. Turn power on
11. Check for green LED indicating Normal operation.
12. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
13. Momentarily increase Reference voltage (±10V max).
14. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
15. Set Reference voltage to maximum value (+/-10V)
16. Check load current at CURRENT MONITOR output
17. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for best
response with no oscillation.
Amplifier Connections
Numbered terminals are on the brown 15-pin connector. Double-letter terminals are on
the orange 4-pin connector. See appendix for connector part numbers.
3
2
1
11
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
1
4
CHASSIS GND
8
15
2
3
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
CONTROLLER
OUT
GND
POWER
SUPPLY
P2 P1
MB4 Card
6
14
TACH
Fig. 4

300 SERIES USER GUIDE
11
Amplifier on Eurocard:Current-Mode, NO Tachometer
Use this checklist for applications that don't employ a tachometer. These include
microprocessor control systems that get position feedback from an encoder on the
motor, as well as non-motor applications such as magnet-coil, solenoids, or other loads
that require a set current from the amplifier in response to a control-voltage at the
inputs. The components on the J17 header come from the factory preset for this
operating mode. See functional diagram on page 2.
1. Connect DC power supply to amplifier +HV and GND. Check voltage to see that is is
within the amplifiers' rating.
2. Ground amplifier to chassis at GND pin DD.
3. Connect motor or load between OUT+ and OUT-. Do not ground load!
4. Connect reference voltage source to REF+ and REF- inputs.
5. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
6. Set REF GAIN pot to full CW.
7. Set FEEDBACK pot to full CW.
8. Set CURRENT LIMIT pot to full CW.
9. Set Vref to 0V
10. Turn power on
11. Check for green LED indicating Normal operation.
12. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
13. Momentarily increase Reference voltage (±10V max).
14. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
15. Set Reference voltage to maximum value (+/-10V)
16. Check load current at CURRENT MONITOR output
17. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for best
response with no oscillation.
Amplifier Connections
Numbered terminals are on the brown 15-pin connector. Double-letter terminals are on
the orange 4-pin connector. See appendix for connector part numbers.
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
CHASSIS GND
AMPLIFIER
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
CONTROLLER
OUT
GND
POWER
SUPPLY
+ Eurocard
C18
A18
C20
A20
C22
A22
C24
A24
C26
A26
C28
A28
C30
A30
C32
A32
C2
A2
A14
C12
A12
C16
Fig. 5

300 SERIES USER GUIDE
12
Amplifier on Eurocard: Current-Mode, WITHTachometer
Use this checklist for applications that do employ a tachometer. These include
microprocessor control systems that get position feedback from an encoder on the
motor, as well as non-motor applications such as magnet-coil, solenoids, or other loads
that require a set current from the amplifier in response to a control-voltage at the
inputs. The components on the J17 header come from the factory preset for this
operating mode. See functional diagram on page 2.
1. Connect DC power supply to amplifier +HV and GND. Check voltage to see that is is
within the amplifiers' rating.
2. Ground amplifier to chassis at GND pin DD.
3. Connect motor or load between OUT+ and OUT-. Do not ground load!
4. Connect reference voltage source to REF+ and REF- inputs.
5. Ground ENABLE,POS ENABLE, NEG ENABLE to amplifier logic ground.
6. Set REF GAIN pot to full CW.
7. Set FEEDBACK pot to full CW.
8. Set CURRENT LIMIT pot to full CW.
9. Set Vref to 0V
10. Turn power on
11. Check for green LED indicating Normal operation.
12. Adjust BALANCE trimpot for 0.0V between OUT+ and OUT-
13. Momentarily increase Reference voltage (±10V max).
14. Check motor direction: is it OK?
YES: continue
NO: remove power, reverse connections to Ref+ and Ref-.
15. Set Reference voltage to maximum value (+/-10V)
16. Check load current at CURRENT MONITOR output
17. Apply step or square-wave signal to Ref-inputs, adjust FEEDBACK CCW for best
response with no oscillation.
Amplifier Connections
Numbered terminals are on the brown 15-pin connector. Double-letter terminals are on
the orange 4-pin connector. See appendix for connector part numbers.
+HV
GND
+
-
DC
OUT+
OUT-
MOTOR
CHASSIS GND
AMPLIFIER
REF+
REF-
ENABLE
POS ENABLE
NEG ENABLE
LOGIC GND
CONTROLLER
OUT
GND
POWER
SUPPLY
+ Eurocard
TACH
C18
A18
C20
A20
C22
A22
C24
A24
C26
A26
C28
A28
C30
A30
C32
A32
C2
A2
C6
C4
A14
C12
A12
C16
Fig. 6

300 SERIES USER GUIDE
13
Power Supply Considerations
1.Determine the maximum voltage required to drive your motor or load at peak current and peak RPM (in
the case of a motor).
Add extra for losses in the amplifier (see p. 10, Output Voltage Swing).
Add an extra 5-10% for power supply ripple.
Use this value, and the amplifier's continuous current rating as your nominal power supply specification
at normal line voltage.
300 series peak currents of 2-2.5X the continuous current rating can usually be tolerated by off-the-shelf
transformer-rectifier-capacitor power supplies.
(See appendix for a complete listing of standard power supplies)
2.Where the amplifier is to be mounted more than 18" away from the power supply filter capacitor, install
a 200uF. (minimum) filter capacitor across the amplifier +HV and Gnd terminals as a local bypass
capacitor. The voltage rating of this capacitor should be compatible with your supply voltage.
3.Use the current monitor output to check for clipping when your system is up and running. This could be
an indication that there is insufficient buss voltage to drive the commanded current through the load.
4.When operating at lower supply voltages, such as 24V or less, check the Normal LED. If it goes out
occasionally, this could mean that the buss voltage 'sag' during periods of high current demand, and is
lowering the buss voltage below the under voltage cutoff point (<16V). If this occurs, consider using a
larger filter capacitor, or raising the supply voltage.
5.If the load has a high inertia, you may need a regenerative energy dissipator, or larger filter capacitors.
Whe a heavy load is decelerated, the amplifier will transfer energy from the motor to the power supply.
This will 'pump-up' the buss voltage, and can cause either an overvoltage shutdown, or damage the
amplifier.
6.If you see the Normal LED go out when the load is decelerated, it is a sign that the buss is "pumping-
up", and you will have to take measures as suggested above, lower the buss voltage, or decelerate the
load more slowly.
7.When multiple amplifiers are connected to the same power supply, use a 'star' wiring configuration.
Don't 'daisy-chain' amplifiers by connecting one to the next, and so on. Make connections between each
individual amplifier and the power supply, and ground each amplifier at pin DD (P1-4 on the MB4 card)
leaving the (-) terminal of the filter capacitor disconnected from ground. Doing this will keep the
reference and logic inputs of the amplifiers referenced to ground, while the voltage at the negative
terminal of the filter capacitor changes in response to the current drawn through the amplifier wiring.
8.Regulated power supplies frequently do not have adequate output filter capacity to power a servo
amplifier. They can go into over-current foldback during periods of high output currents. If using such
supplies, it may be necessary to add an external filter capacitor (4-5000 uF).
Multiple Amplifier Power Connections
AA
DD
AA
DD
AA
DD
AA
DD
DON'T AA
DD
AA
DD
AA
DD
+
-
+
DO THIS
DO
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POWER
SUPPLY
POWER
SUPPLY
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Fig. 7

300 SERIES USER GUIDE
14
Minimum Inductance
Table 3 lists the minimum inductance required for various amplifier and buss voltage
combinations.
Model 20V 40V 80V 160V
303,303B 63 uH 125 uH 250 uH N/A
306,306A,306AB 30 uH 63 uH 125 uH N/A
312 N/A 175uH 350uH 700 uH
Table 3
Maximum Inductance
There is no maximum inductance specified for the 300 series, however larger
inductances can reduce the bandwidth and produce excessive ringing in the amplifier's
response. The Standard column in the table below shows the load inductance which are
considered 'normal' for the 300 series amplifiers. The Dash-1 column shows the range of
load inductance which can be driven with amplifiers ordered with the -1 option (see
ordering guide in appendix). Load inductance higher than the maximum values in the
Dash-1 column will result in lower bandwidth, and may require component changes to
optimize compensation.
Model 40V 80V
Standard Dash-1 Standard Dash-1
303, 303B 63 uH to 1.9 mH 2 to 9 mH 125 uH to 3.9 mH 4 to 18 mH
306, 306A, 306AB 32 uH to 0.9 mH 1 to 4.5 mH 64 uH to 1.9 mH 2 to 9 mH
312 88 uH to 5.4 mH 5.5 to 25 mH 175 uH to 10.9 mH 11-50 mH
Table 4
Bandwidth
The bandwidth of an amplifier is the frequency at which the amplitude of the output
drops to 70% of the value at a much lower frequency. The effect of bandwidth is to
either limit the frequency of a sine-wave signal that can be amplified, or to limit the
risetime of a step-input signal. The type of load will also have an effect on the
bandwidth, particularly as the inductance increases.
Amplifiers with the -1 option (high inductance loads) will exhibit the specified
bandwidth at higher values of inductance than the standard amplifiers.
Table 5 shows the load inductance and resistance at which the standard and -1 option
amplifiers are rated for their 3 kHz bandwidths. As the load inductance increases beyond
the values listed in table 5, the bandwidth will decrease.
Model BW R L (std) L (-1)
303,303B 3kHz 2.5 250 uH 4 mH
306,306B 3kHz 1.0 125 uH 2 mH
306A,306AB 3kHz 1.0 125 uH 2 mH
312 3kHz 14 700 uH 11 mH
Table 5
BW ; -3dB small-signal bandwidth
R ; Load resistance in ohms
L (std) ; Load inductance in microhenries for standard amplifier
L (-1) ; Load inductance in millihenries for amplifiers with -1 option

300 SERIES USER GUIDE
15
Enable Inputs
The polarity of the amplifier's output can be controlled with the Positive and Negative
enable inputs, and the outputs can be completely disabled with the Enable input.
Output polarity control is usually used on motion control systems that use travel -limit
switches. If a moving member hits one of these switches, it is supposed to disable the
amplifier, preventing further travel into a mechanical stop. At the same time, it should be
possible to reverse the direction of the motor to 'back-out' of the limit. Positive and
Negative enable inputs are provided for this function.
For a shutdown of the amplifier (both outputs off), use the Enable input. This signal will
also cause the Normal LED to turn off, and the Normal output to go LO.
The enable inputs use +5V logic signals, external dry-contact, or NPN current-sinking
drivers. Ground is the level required to make the function logically true, and +5V (or
open-circuit) will make the function false (true = enabled, false = disabled).
The Enable signal only may have its' true logic-level inverted by removing the jumper in
header J17 at position-9 (see functional diagram). When this is done, leaving the Enable
input open, or at +5V will enable the amplifier, and grounding it will shut it down.
Note: The Positive and Negative Enable inputs must always be grounded to enable the
respective outputs.
Current Monitor
This is a signal that is a measure of the output current of the amplifier.
The scale factor in amps/volt is listed below. All of the 300 series output a +/-6V signal
when the current is at the peak rated value.
Amplifier Amps/Volt
303,303B 2.0 Table 6
306, 306B 4.17
306A,306AB 5.0
312 1.5
Status LED
A green Normal LED is on the basic amplifier, the MB4 card, and Eurocard.
It will be ON when operation is Normal:
Buss voltage is within normal limits.
Enable input is true. (See above for details on Enables)
Chassis temperature is <83°C.
No short circuits between outputs, or between outputs and ground.
It will be OFF during a fault condition:
Buss voltage is over or under normal limits.
Enable input is false.
Chassis temperature is >83°C.
A short-circuit has occurred at the outputs.
The short-circuit, and overtemp faults are latching type, that is, they will disable the
amplifier until power is cycled off and on, or until the Reset input is toggled.
Note: The Positive and Negative enable inputs will not affect the status of the Normal
LED or Normal output.

300 SERIES USER GUIDE
16
Normal Output
This is a +5V CMOS output signal in series with an internal 1.87K resistor.
It will be HI (+5V) when the Normal LED is on, and LO (ground) when the Normal
LED is off. It can drive an external low-current LED, or CMOS logic compatible inputs
to user equipment.
Reset Input
A +5V CMOS logic input which is normally pulled-up to +5V by an internal 100K
resistor. Ground this signal momentarily to reset a fault condition caused by overtemp, or
output short-circuit.
Do not ground this input continuously, as this could cause overloading of the output
stage of the amplifier. If you want to shutdown the amplifier, use the Enable input.
Current Limit
On the basic amplifier, component R8 on header J17 controls the maximum current
delivered by the amplifier. A value of 10K ohms is standard and will let the amplifier
deliver the maximum rated peak current. Substitute smaller values to reduce the limiting
current.
The MB4 and Eurocard come with potentiometers that lets you adjust the maximum
current to any set value from 0, to the maximum rated peak current.
In either case, whenever the current-limit is greater than the continuous current rating of
the amplifier, it will fold-back to the continuous current rating after 1 second for unipolar
currents, or 2 seconds for bipolar currents.
Output Voltage Swing
300 series amplifiers use MOSFET transistors in the output stages. These have no
inherent 'saturation' voltage like bipolar transistors. Instead, they look like low value
resistors in series with the power supply. The table below lists the on-resistance and
output voltage-drop for the various amplifiers.
Note that output voltage swing is relative to the instantaneous supply voltage. Therefore,
if you have an application that requires a particular voltage swing, you must add to this
the output voltage-drop, power supply ripple voltage, and use this as your low-line power
supply operating voltage.
Amplifier Rout Vsat
303,303B 0.26 3.12
306,306B 0.13 3.25
306A,306AB 0.13 3.9
312 0.60 5.4
Table 7
Rout is the amplifier output resistance.
Vsat is the voltage-drop (also called saturation voltage) across the amplifier at peak
current.