Glentek GA4571PR2, Руководство по эксплуатации и обслуживанию

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GLENTEK Inc. 208 Standard Street, El Segundo, California 90245, U.S.A. (310) 322-3026 22
GA45-71PR2/76PR2/81PR2/82PR2 MANUAL
put terminal of the amplifier. A step voltage can be simulated by applying and removing a flashlight battery
to the Signal Input. For this purpose, the battery is usually mounted inside of a small box with a switch.
Common names used to describe this DC signal voltage source are Battery Box or DC Simulator. Elabo-
rate signal sources made for this purpose often include bipolar output, potentiometer output adjust and po-
larity reversing switches, etc. You often hear the phrase
“DC Box the velocity loop servo” used by peo-
ple working on servo systems.
(This Signal Box may be purchased from Glentek Inc., Part Number BB700)
3. At this point the motor should be running smoothly. While applying and removing the DC input signal, ad-
just the Current-Limit potentiometer, R17, for desired maximum acceleration and deceleration. Motor cur-
rent should be observed by using an oscilloscope at TB201-7. The scale factor of this voltage is 1V = 15A
or 1V = 25A depending on the model. Leave the Current-Limit potentiometer at this setting for all remaining
adjustments.
4. Adjust the Signal-Gain potentiometer, R12, or the Aux Signal-Gain potentiometer, R13, (depending on the
input you are using) so that when you apply the DC signal the motor rotates at approximately 400 RPM.
5. Observe the tachometer voltage with an oscilloscope while applying and removing the DC input signal.
You will observe one of three possible waveforms: critically damped, under damped, or over damped (see
figure 6.4).
6. The optimum waveform for most systems is the critically-damped waveform. If the waveform that you are
observing is critically damped, proceed to step 9.
7. If your waveform is under damped, make the following adjustments:
Turn the Compensation potentiometer, R16, CCW until the waveform becomes critically damped. Note
here that the limiting factor will be motor oscillation or “hunting”. You must always leave the Compensation
potentiometer far enough CW so that the velocity loop remains stable.
If the waveform is still under damped after adjusting the Compensation potentiometer for maximum band
width, turn the Tachometer-Gain potentiometer, R14, 2 turns CCW and then adjust Compensation potenti-
ometer, R16, CCW until waveform becomes critically damped. Repeat procedure if necessary. Again, the
servo velocity-loop must at all times remain stable. Consult the factory if necessary.
8. If the waveform is over damped, make the following adjustments:
Turn the Tachometer-Gain potentiometer, R14, CW until a slight overshoot appears on the waveform; then
turn the Compensation potentiometer, R16, CCW until a critically damped waveform is observed.
9. Now that the waveform is critically damped, leave the Compensation, R16, and Tachometer Gain, R14, at
these settings for all remaining adjustments and operations.
10. Next, set the Signal potentiometer, R12 or R13, to the gain required by your system (e.g.10 volts = 2000
RPM).
11. Adjust Balance potentiometer, R15, one more time to null out any offset (with 0 volt input).
12. For all remaining adjustments when placing the amplifier in your system only the Signal potentiometer,
R12 or R13, and Balance potentiometer, R15, should be adjusted.