Glentek GA369 Installation and operating instructions

OPERATION
&
SERVICE MANUAL
Model GA369
Pulse Width Modulated
Servo Amplifier

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GA369 MANUAL
TABLE OF CONTENTS
CHAPTER ONE: INTRODUCTION
1.1 INTRODUCTION TO THE GA369 MANUAL .......................................................5
CHAPTER TWO: DESCRIPTION AND SPECIFICATIONS
2.1 DESCRIPTION OF THE GA369......................................................................... 6
2.2 AVAILABLE OPTIONS AND MODEL NUMBERING........................................... 6
2.2.1 SIGNAL INPUT................................................................................................. 6
2.2.2 VELOCITY MODE OR CURRENT MODE OPTIONS........................................ 6
2.2.3 + AND -LIMITS ................................................................................................. 6
2.2.4 TOTAL INHIBIT................................................................................................ 6
2.2.5 CARRIER FREQUENCY.................................................................................. 6
2.2.6 MULTI-AXES CONFIGURATIONS ................................................................... 6
2.2.7 EXAMPLE -MODEL NUMBERING.................................................................... 7
2.3 PROTECTION CIRCUITS................................................................................. 7
2.3.1 DRIVE INHIBIT INDICATOR OPERATION (RED LED)..................................... 7
2.3.2 LOW SPEED ELECTRONIC CIRCUIT BREAKER (RED LED).......................... 7
2.3.3 HIGH SPEED ELECTRONIC CIRCUIT BREAKER (RED LED)......................... 7
2.4 SPECIFICATIONS.............................................................................................. 7
2.4.1 OUTPUT POWER ............................................................................................ 7
2.4.2 INPUT POWER................................................................................................ 7
2.4.3 SIGNAL INPUTS.............................................................................................. 8
2.4.4 OTHER INPUTS AND OUTPUTS..................................................................... 8
2.4.5 MECHANICAL (ALSO SEE APPENDIXES B4-B7 AND Bi0-B13)...................... 8
2.4.6 TYPICAL FACTORY SETTINGS ...................................................................... 8
CHAPTER THREE: PERSONALITY PREAMP CARD
3.1 INTRODUCTION TO THE PERSONALITY PREAMP CARD (GA369-3)............ 9
3.1.1 VELOCITY MODE PERSONALITY PREAMP CARD ........................................ 9
3.1.2 CURRENT MODE PERSONALITY PREAMP CARD......................................... 9
3.2 DESCRIPTION OF OPTIONS AND ADJUSTMENTS......................................... 9
3.2.1 POTENTIOMETER ADJUSTMENTS................................................................ 9
3.2.2 INPUT AND OUTPUT SIGNALS...................................................................... 10
3.3 REMOVAL AND INSTALLATION..................................................................... 10
3.4 TROUBLE SHOOTING WITH THE PERSONALITY PREAMP CARD.............. 10
CHAPTER FOUR: THEORY OF OPERATION
4.1 INTRODUCTION TO THEORY OF OPERATION............................................. 11
4.2 OPERATION OF OUTPUT SWITCHING TRANSISTORS................................ 11
4.3 “H TYPE” OUTPUT BRIDGE CONFIGURATION ............................................. 11
4.4 PULSE WIDTH MODULATION (PWM) ............................................................ 11
4.5 CURRENT LOOP OPERATION....................................................................... 12
4.6 VELOCITY LOOP OPERATION....................................................................... 13
CHAPTER FIVE: INSTALLATION PROCEDURE
5.1 MOUNTING...................................................................................................... 14
5.2 WIRING SIZE AND PROPER TECHNIQUE..................................................... 14
5.3 BASEPLATE CONNECTIONS ......................................................................... 14
5.3.1 INPUT FROM SECONDARY OF POWER TRANSFORMER ........................... 14
5.4 AMPLIFIER MODULE CONNECTIONS AND FUNCTIONS ............................. 14
5.4.1 D.C. BUSS ...................................................................................................... 14
5.4.2 MOTOR........................................................................................................... 15
5.4.3 SIGNAL INPUT................................................................................................ 15
5.4.4 TACHOMETER INPUT.................................................................................... 15
5.4.5 CURRENT SENSE.......................................................................................... 15
TABLE OF CONTENTS

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GA369 MANUAL
TABLE OF CONTENTS
5.4.6 + AND -LIMITS............................................................................................... 15
5.4.7 TOTAL INHIBIT............................................................................................... 15
5.4.8 FAULT MONITOR........................................................................................... 15
5.4.9 RESET............................................................................................................ 15
CHAPTER SIX: START UP AND ADJUSTMENT PROCEDURE
6.1 SAFETY PRECAUTIONS................................................................................. 16
6.2 AMPLIFIER ALIGNMENT INTRODUCTION ..................................................... 16
6.3 VELOCITY LOOP PHASING ............................................................................ 16
6.4 TACH GAIN ADJUSTMENT.............................................................................. 16
6.5 CONNECTING AMPLIFIER TO DIGITAL POSITION LOOP............................. 17
CHAPTER SEVEN: MAINTENANCE, REPAIR AND WARRANTY
7.1 MAINTENANCE INTRODUCTION.................................................................... 19
7.2 REPAIR ............................................................................................................ 19
7.2.1 FAULT TRACING............................................................................................ 19
7.2.2 FAULT TRACING CHARTS............................................................................. 19
7.2.3 PART REPLACEMENT ................................................................................... 19
7.2.4 LOW SPEED ELECTRONIC CIRCUIT BREAKER (LS/ECB) SHUTDOWN...... 19
7.2.5 HIGH SPEED ELECTRONIC CIRCUIT BREAKER (HS/ECB) SHUTDOWN..... 19
7.3 FACTORY REPAIR .......................................................................................... 20
7.4 WARRANTY..................................................................................................... 20
APPENDIX A: FAULT TRACING CHARTS
FAULT CHART 1 Motor does not turn in either direction........................................ 22
FAULT CHART 2 Motor only turns in one direction................................................ 23
FAULT CHART 3Motor wanders and hunts or does not track smoothly................ 23
FAULT CHART 4Motor does not develop maximum output speed
(no load applied) in either direction............................................ 24
FAULT CHART 5Motor does not develop max output torque in either direction .... 25
ENGINEERING NOTES FOR FAULT TRACING CHARTS....................................... 26
APPENDIX B: AMPLIFIER DRAWINGS
INSTALLATION SCHEMATIC (GA369) -(369-1007).................................................. 28
ASSEMBLY CONTROL BOARD (GA369-1) -(369-1002)........................................... 29
INSTALLATION DIAGRAM (GA369-1) -(369-1008)................................................... 30
INSTALLATION DIAGRAM (GA369-2A-2) -(369-1205)............................................. 31
INSTALLATION DIAGRAM (GA369-4A-4) -(369-1207)............................................. 32
INSTALLATION DIAGRAM (GA369-6A-6) -(369-1211)............................................. 33
INSTALLATION DIAGRAM (GA369-8A-8) -(369-1209)............................................. 34
APPENDIX C: PERSONALITY PREAMP
SCHEMATIC PERSONALITY PREAMP (369-1200)................................................. 36
ASSEMBLY PERSONALITY PREAMP (369-1202)................................................... 37

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GA369 MANUAL
INTRODUCTION
1.1 INTRODUCTION TO THE GA369 MANUAL:
This manual is intended for use with Glentek’s TORQUE-SWlTCHTM series, model GA369 Pulse-Width-Modulated
(PWM) servo amplifiers. It provides all of the information that is required for installation, alignment and maintenance
of the GA369. We suggest that you take the time to read this manual from cover to cover before trying to work with a
GA369 amplifier. If you have any questions that you can not find the answer to in this manual please feel free to call
and discuss your problem or question with a Glentek applications engineer. Having been in the servo system busi-
ness for over 26 years, we have a vast pool of applications knowledge waiting to help you.
Thank you for using Glentek’s products. It is our goal to save you money, time and provide you with a superior prod-
uct.
CHAPTER ONE: INTRODUCTION

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GA369 MANUAL
CHAPTER TWO: DESCRIPTION, AND SPECIFICATIONS
2.1 DESCRIPTION OF THE GA369:
The GA369 are modular, high power, high bandwidth PWM servo amplifiers designed for use with DC permanent
magnet servomotors. The GA369 utilize todays latest technology in power semiconductors for high efficiency which in
turn makes the amplifiers extremely reliable in today’s and tomorrow’s demanding applications.
2.2 DESCRIPTION OF AVAILABLE OPTIONS AND MODEL NUMBERING
INFORMATION:
2.2.1 SIGNAL INPUT:
The GA369 is available with two signal inputs, one single-ended and one differential. The differential input is
marked Aux. and Aux. Ret. and may be connected single ended by grounding Aux. Ret. (Refer to Appendix C,
drawings 369-1200 and 369-1202).
2.2.2 VELOCITY MODE OR CURRENT MODE OPTIONS:
The GA369 are most often used to close a critically damped velocity loop using a DC tachometer for velocity
feedback. However, this high gain input summing amplifier can be bypassed providing an input directly to the
current loop amplifier. The part number designator for this Current Mode option is CM and follows next in the
sequence of part number (Ex. :GA369CM). If the CM is absent from the part number, the amplifier will be
configured for Velocity Mode (Refer to Appendix C, drawings 369-1200 or 369-1202).
2.2.3 + AND -LIMITS:
The GA369 may be configured for three different end of travel limit circuits with pull-up resistors (4.7k) to either
+ 5VDC or +1 5VDC. (Refer to Appendix C, drawing 369-1200)
Type A: Requires grounding of pin 8 or pin 9 to disable amplifier. To implement type A limits refer to appendix
B, drawing 369-1200.
Type B: Requires a positive voltage at pin 8 or pin 9 to disable amplifier. To implement type B limits refer to
Appendix B, drawing 369-1200.
Type C: Requires the removal of a ground from pin 8 or pin 9 to disable amplifier. To implement type C limits
refer to Appendix B, drawing 369-1200.
The amplifier is normally shipped with the type A + and -limit configuration with +1 5V pull-up resistors.
Designation letter A, B or C is added next to the part number to indicate type of limit circuit desired (Ex. :
GA369CMA-1, would have type A limits).
2.2.4 TOTAL INHIBIT:
The GA369 may be configured for three different Total Inhibit circuits (See 2.2.3 + AND -LIMITS above and
refer to drawing 369-1200). The amplifier is normally shipped with type A Total Inhibit.
2.2.5 CARRIER FREQUENCY:
The GA369 is provided with a carrier frequency of 10 KHz. Other carrier frequencies are available consult
Glentek.
2.2.6 MULTI-AXES CONFIGURATIONS:
The single and multi-axes part number designators are as follows:
GA369-1Single amplifier module.
GA369-2A-12 Axes chassis with 1 Amplifier module.
GA369-2A-22 Axes chassis with 2 Amplifier modules.
GA369-4A-34 Axes chassis with 3 Amplifier modules.
GA369-4A-44 Axes chassis with 4 Amplifier modules.
GA369-6A-56 Axes chassis with 5 Amplifier modules.
GA369-6A-66 Axes chassis with 6 Amplifier modules.
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: DESCRIPTION, FEATURES AND SPECIFICATIONS

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GA369 MANUAL
2.2.7 EXAMPLE -MODEL NUMBERING:
The following example of GA369 part numbering, is provided to help you better understand Glentek’s part
numbering system:
Example:GA369CMA-4A-3
In this example, the GA369 part number describes the following amplifier configuration:
CM = Current Mode input option A Type A + and -Limit option.
-4A = 4 Axes chassis -3 = 3 Amplifier modules installed.
For this example each of the three amplifier modules would be labeled GA369-1 or GA369-1 with serial
number and CMA designator at bottom of label. The 4 axes chassis would be labeled GA369-4A-3 with serial
number and CMA designator at bottom of label.
2.3PROTECTION CIRCUITS:
The following protection circuits are integral to the GA369 amplifiers to prevent damage to the amplifier and your
equipment. Again, Glentek is anxious to work with you in helping to implement any circuit functions your system might
require.
Note: For 2.3.1 to 2.3.3 refer to Appendix B, drawing 369-1007.
2.3.1 DRIVE INHIBIT INDICATOR OPERATION (RED LED):
The LED 1 Drive Inhibit indicator light will turn ON and latch for the two following conditions:
1. Low Speed Electronic Circuit Breaker (LS/ECB) triggered.
2. High Speed Electronic Circuit Breaker (HS/ECB) triggered.
2.3.2 LOW SPEED ELECTRONIC CIRCUIT BREAKER:
This circuit protects the motor, amplifier and mechanical system from damage due to excessive mechanical
bind in the system or possibly driving into a hard mechanical stop. Circuit operation is as follows:
When the motor current exceeds the value set at TP1, typically 3.0 VDC (scale factor 1 VOLT=2 AMPS), IQ3-1
switches positive and voltage on C5 begins integrating up. If the current remains above the set point, typically
0.5 seconds, Q9 will trigger the ECB latch and the Drive Inhibited indicator.
2.3.3HIGH SPEED ELECTRONIC CIRCUIT BREAKER:
This circuit protects the amplifier from dead shorts across the amplifier output terminals. The HS/ECB is always
factory set and should not be adjusted. The typical factory setting is 29 Amps for 10 micro seconds. Again, this
circuit triggers the ECB latch and the Drive Inhibited indicator.
2.4 SPECIFICATIONS:
The specifications for each GA369 amplifier module is as follows:
2.4.1 OUTPUT POWER
OUTPUT CURRENT (PEAK): ±12 AMPS
OUTPUT CURRENT (RMS): ±6 AMPS
DC BUSS VOLTAGE: +35VDCTO +7OVDC
(Higher and lower Buss Voltages available, consult Glentek.)
Note: DC Buss voltage should be selected approximately 10%-20% above the maximum voltage required
at motor terminals for maximum system efficiency.
2.4.2 INPUT POWER:
INPUT POWER FOR DC BUSS: A fused single or three phase full wave rectifier and filter capacitor are
provided on the base plate. The AC input to this circuit is supplied by a separately mounted power transformer
unique to the application. The power transformer and motor output inductors are not standard parts of the
amplifier package. Glentek has power transformers and inductors in stock for your system requirements.
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: DESCRIPTION, FEATURES AND SPECIFICATIONS

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GA369 MANUAL
2.4.3 SIGNAL INPUTS:
VOLTAGE,MAXIMUM
Aux. Input ±13 Volts
Sig. Input ±70 Volts
Tach. Input ±90 Volts
Input Impedance, Minimum 10K Ohm
GAIN,MAXIMUM
Sig. and Aux. Inputs 15,000 Amps/Volt
Tachometer 7,000 Amps/Volt
Drift (Ref. to Input), Maximum 0.01 mV/°C
Frequency Response, Minimum 750 Hz
Dead Band None
Form Factor 1.01
2.4.4 OTHER INPUTS AND OUTPUTS
+and -Limits (Type “A’1) Activated by a 3ma. contact closure to common.
Total Inhibit (Type “A”) Activated by a 3ma. contact closure to common.
Gnd. to resetActivated by a 3ma. contact closure to common.
Fault Monitor 4.7k ohm pull-up to +5VDC or + 15VDC ,will sink 50 ma.
2.4.5 MECHANICAL (SEE APPENDIXES B4-B7)
Mounting Any Position
Height 7 inches
Cooling 50°C Ambient Max.
Baseplate
GA369-2A-26.25 in. x 8.8 in.
GA369-4A-46.25 in. x 12.2 in.
GA369-6A-66.25 in. x 19.0 in.
Weight
GA369-11.14 lbs.
GA369-2A-25.1 lbs.
GA369-4A-47.5 lbs.
GA369-6A-69.5 lbs.
2.4.6 TYPICAL FACTORY SETTINGS
Sig. and Aux. Gain 5V(Sig.)/7V(Tach.)
Tach. Gain 50%
Loop Gain CCW (OFF)
Comp. CW (Mm. Bandwidth)
LS/ECB 6A @ 0.5 sec.
HS/ECB 29A ~ 10 micro sec.
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GA369 MANUAL
CHAPTER THREE: PERSONALITY PREAMP CARD
3.1 INTRODUCTION TO THE PERSONALITY PREAMP CARD (GA369-3):
The Personality Preamp card is a modular plug-in card that comes in two versions: velocity mode and current mode.
Schematic and Board Assembly prints for this card are found in Appendix C, drawing numbers 369-1200, 369-1202
and will be referred to in the following description.
The Personality card contains the main high gain preamp with all associated system alignment adjustments. This
card greatly enhances system troubleshooting and repair; in that if an amplifier should fail, simply remove the
Personality card (which has all of the original system constants adjusted in) and replace it on a spare amplifier. This
eliminates system realignment when changing out amplifiers. Also, a motor-tach-load may be aligned at the factory
and then just the Personality card sent to the field for system test.
3.1.1 VELOCITY MODE PERSONALITY PREAMP CARD:
The Velocity Mode Preamp Card contains the main high gain preamp with all the associated system alignment
adjustments to close a velocity loop using a D.C. tachometer for velocity feedback. (Refer to Appendix C,
drawings 369-1200 and 369-1202)
3.1.2 CURRENT MODE PERSONALITY PREAMP CARD:
The Current Mode Personality Card contains all the system alignment adjustments to control a current mode
amplifier. (Refer to Appendix C, drawings 369-1200 and 369-1202)
3.2 DESCRIPTION OF OPTIONS AND ADJUSTMENTS:
The Personality Preamp card is a small printed circuit card (3.3” x 4.3”) standing on two 12 pin connectors (0.45” tall)
that mate with appropriate sockets on the amplifier control board.
The Personality card is most often used to close a velocity loop using a DC tachometer for velocity feedback.
However, the high gain input summing amplifier can be bypassed providing an input directly to the current loop
amplifier (Current Mode option). If the Current Mode (CM) option is specified the Velocity Mode Personality Preamp
Card is converted to a Current Mode Personality Preamp Card. (Refer to Appendix C, drawings 369-1200 and 369-
1202)
3.2.1 POTENTIOMETER ADJUSTMENTS:
The following is a description of the potentiometer adjustments used for the two modes of operation. Please
refer to Chapter Six on Start Up and Adjustment Procedures for a detailed description of how to set these
potentiometers.
VELOCITY MODE: (Refer to Appendix C, drawings 369-1200 and 369-1202)
R15 Signal Gain potentiometer sets the input voltage to output RPM required by your system for the single-
ended input. (Ex.: 10 VOLTS INPUT = 2000 RPM)
R45 Auxiliary Signal Gain potentiometer sets the input voltage to output RPM required by your system for the
differential signal input (Ex.: 10 VOLTS INPUT = 2000 RPM).
R21 Tachometer Gain potentiometer sets the amount of tach signal required by your system. Use in
conjunction with the Compensation potentiometer, R16, to adjust the system bandwidth.
R43 Balance potentiometer used to null out any DC offset in the amplifier (Ex.: 0 VDC INPUT = 0 RPM).
R55 Compensation potentiometer sets the amount of bandwidth (frequency response) required by your
system. Use in conjunction with the Tachometer Gain potentiometer, R14, to adjust the system bandwidth.
R57 Current Limit potentiometer sets the maximum acceleration and deceleration current.
R59 Loop Gain potentiometer used to reduce the velocity loop gain to zero when the system is first turned on
to prevent run away operation. Before turning the system on for the first time this potentiometer is set fully
CCW to command zero current to the motor. Once the system is correctly phased this potentiometer is set fully
CW for all further system adjustments.
CURRENT MODE: (Refer to Appendix C, drawings 369-1200 and 369-1202)
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R15 Signal Gain potentiometer sets the input voltage to output current required by your system for the single-
ended input. (Ex.: 5 VOLTS INPUT = 2 AMPS OUTPUT CURRENT)
R45 Auxiliary Signal Gain potentiometer sets the input voltage to output RPM required by your system for the
differential signal input (Ex.: 5 VOLTS INPUT = 2 AMPS OUTPUT CURRENT).
R57 Current Limit potentiometer sets the maximum acceleration and deceleration current.
R59 Loop Gain potentiometer is factory set to prevent amplifier maximum rated current from being exceeded
when the current limit potentiometer is fully CW.
R43 Balance potentiometer used to null out any DC offset in the amplifier. (Ex.: 0 VDC INPUT = 0 CURRENT
OUTPUT)
3.2.2 INPUT AND OUTPUT SIGNALS:
Connector P2 Pin No. (Signals to and from connector J1)
1AUXILIARY Differential signal input.
2AUXILIARY RETURN Differential signal input.
3SIGNAL Single-ended signal input.
4SIGNAL COMMON Signal common.
5TACHOMETER Tachometer signal input.
6TACHOMETER COMMON Signal common.
7RESET Resets amplifier after a fault (input).
8+ LIMIT Inhibits motor rotation in the + direction (input).
9-LIMIT Inhibits motor rotation in the -direction (input).
10 TOTAL INHIBIT Inhibits motor rotation in the both directions (input).
11 COMMON Signal common and ± 15 VDC common.
12 FAULT Fault monitor output.
Connector P3 Pin No. (Signals to and from power board)
1INHIBITTotal inhibit output.
2CURRENT SIGNAL Velocity error or current command output.
3CURRENT SENSE Current sense input.
4+ LIMIT+ Limit output.
5-LIMIT -Limit output.
6+15VDC + 15VDC power.
7COMMON ± 15 VDC and signal common.
8COMMON ± 15 VDC and signal common.
9COMMON ± 15 VDC and signal common.
10 -15 VDC -15 VDC power.
11 FAULT Fault input.
12 RESET Reset output.
3.3 REMOVAL AND INSTALLATION:
When removing or installing the Personality Preamp card, care must be taken not to damage any of the
components under the card on the amplifier controller board or on the Personality card.
Removal: Remove the retaining screw hold the Personality card by its edges and pull straight away from the
amplifier controller board (Do not pull on the components). For amplifiers with Personality card mounted vertically,
remove amplifier module first before unplugging Personality card.
Installation: Hold the Personality card by it’s edges and carefully align the two 12 pin connectors with their mating
sockets and push straight toward the amplifier controller board until it is firmly seated (Do not press on any of the
components) and replace the retaining screw.
3.4 TROUBLE SHOOTING WITH THE PERSONALITY CARD:
If your system exhibits a problem and a working amplifier module is available fault tracing can be expedited by
removing the Personality Preamp card from the malfunctioning amplifier, plugging it into the replacement amplifier
and testing the system. If the system does not work with the new amplifier module, Refer to Chapter Seven on
Maintenance and Repair for a more detailed fault tracing procedure. However, if the system does work with the new
amplifier module, check the malfunctioning unit for loose connections and retest the suspected unit in the system.
CHAPTER
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GA369 MANUAL
CHAPTER 4: THEORY OF OPERATION
CHAPTER FOUR: THEORY OF OPERATION
4.1 INTRODUCTION TO THEORY OF OPERATION:
A Velocity Mode servo amplifier is essentially comprised of two control loops (see fig. 4.1).
The inside control loop is referred to as the Current Loop and the outside loop is referred to as the Velocity Loop.
Before we begin our analysis of the Current Loop, let us review some basic concepts which will help you to better
understand the amplifier’s operation.
4.2 OPERATION OF OUTPUT SWITCHING TRANSISTORS:
The output transistors, for all intents and purposes, operate in only two states. They are analogous to an ON/OFF
switch. When an output transistor is OFF, there is no current flowing through it (it’s resistance is infinite). When an
output transistor is ON, current flows through it (it’s resistance is near zero). When the transistor is ON, it is techni-
cally referred to as being in saturation.
4.3 “H TYPE” OUTPUT BRIDGE CONFIGURATION:
The output configuration of the amplifier is a “H TYPE” bridge (see fig. 4.2 for schematic representation of output
bridge with motor connected).
The advantage of an “H TYPE” output bridge configuration is that by controlling the switching of the opposite pairs of
transistors, current can be made to flow through the motor in either direction using a single polarity power supply as
shown in figure 4.2.
To provide motor current in one direction, A and C are turned ON, while B and D remain in the OFF state. To provide
motor current in the other direction, B and 0 are turned ON, while A and C remain in the OFF state.
4.4 PULSE-WIDTH-MODULATION (PWM):
Pulse-Width-Modulation is the technique used for switching opposite pairs of output transistors ON and OFF to
control the motor drive current. When zero current is commanded to the current loop, the opposite pair of transistors
are turned ON and OFF as shown in figure 4.3. Note that since the pulse widths are equal, the net DC current in the
motor is equal to zero.
Figure 4.1
Velocity mode sevo loop
for a brush type motor
Figure 4.2
Schematic representation of
an output bridge with a
motor connected.