Electronics AC - Manual (Page 16)

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FIGURE 2. FRONT PANEL DESCRIPTION - (Technical Adjustments)
1. SPAN ADJUST - Please do not adjust the Span. This is a factory setting. Do not remove the cali-
bration sticker.
2. ZERO ADJUST - Please do not adjust the Zero. This is a factory setting. Do not remove the cali-
bration sticker.
3. AUTO-ZERO SWITCH - Used to activate or deactivate the auto-zero function. Auto-zero forces
the digital display to zero whenever the enable signal and the motor are off. The Auto-zero blue
LED indicator will show that it is active.
4. SERVO GAIN - Used to adjust the gain of the error amplifier in the servo. High gain requires less
error to cause servo correction. Turn clockwise for more gain. If the gain is too high, the servo
may be unstable.
5. SERVO RESET - Used to adjust the speed of the servo response. Faster reset allows faster re-
sponse to an error condition. Turn clockwise for faster reset. If the reset is too fast, the servo may
be unstable.
6. ALARM DELAY TIME - Used to set the time allowed before the alarm relay contact will operate.
The high or low alarm LED's will go to a bright condition when this timer expires. The range is 0-
10 seconds.
7. ALARM BANDWIDTH - Used to set the amps width of the alarm zone. The Alarm Bandwidth
is adjustable from 0% to 50%. The alarm midpoint follows the command Setpoint. Push the dis-
play switch left to display alarm bandwidth.
8. DISPLAY RANGE FINE - Used to adjust the digital display range to the full scale (current trans-
former) range desired.
9. DISPLAY RANGE COARSE - Used to select the digital display range to the full-scale range
(current transformer) desired.
10. DIGITAL DISPLAY DECIMAL POINT - Used to select the decimal point position on the digital
display. Choices are: 1000 / 100.0 / 10.00.
11. SERVO SWITCH - Used to control the servo. Up is "on” for automatic servo control. Down is "off”
for manual operation. The alarms do not function and no motor amps servo correction is provided
when the servo is off.
12. SETPOINT LOCAL / REMOTE - Used to select the Setpoint command from the front panel knob
or from an external remote analog 0-10 Vdc command.
13. FREQUENCY ADJUST - Factory set at 8 Hertz. Adjusts the frequency of the pulse output signal
to the MagnaValve. The new 1xxx series MagnaValves can be set to 15-25 Hertz.
14. ENABLE DELAY – Used to adjust the time delay (0-10sec.) from receipt of enable Signal until
valve output. Useful in direct pressure blasting machines to allow air pressure to stabilize prior to
starting the valve. For suction blast or wheel-blast machines this should be set to zero.