Electronics FC - Manual (Page 11)

11
15. FIGURE 2 FRONT PANEL (Technician Adjustments)
ITEM
DESCRIPTION
1. SPAN - Used to adjust the amplitude of the feedback signal and is factory set to convert 0-5Vdc
to 0-10Vdc. Flow calibration adjustments for catch and weigh test should be made at the Mag-
naValve.
Please do not adjust the SPAN. This is a factory adjustment. Do not remove the calibra-
tion sticker.
2. ZERO - Used to adjust the input signal on the Digital Display to zero during a no flow condition. .
3. AUTO-ZERO SWITCH - Will activate or deactivate the Auto-Zero function. Auto-Zero forces the
Digital display to zero whenever the enable signal is off. The Auto-Zero blue LED indicator will
show that it is active. It may not be necessary to zero the display using the “ZERO” trimpot when
switching the Auto-Zero “On” or “Off”.
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 gain is too high the servo may
be unstable.
5. SERVO RESET - Used to adjust the speed of servo response. Faster reset allows faster re-
sponse to an error condition. Turn clockwise for faster reset. If 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 width of the alarm zone. Turn fully counter-clockwise for
0% alarm bandwidth or clockwise for increasing alarm bandwidth up to ± 50%. The alarm mid-
point follows the command setpoint. Push the display switch to left to display alarm bandwidth.
8. DISPLAY RANGE FINE - Used to adjust the Digital Display range to the full-scale range desired.
Turn clockwise for larger values.
9. DISPLAY RANGE COARSE - Used to adjust the Digital Display range to the full-scale range de-
sired. Turn clockwise for larger values.
10. DIGITAL DISPLAY DECIMAL POINT - Switch is used to choose the decimal point position in
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 flow rate servo correction is pro-
vided when the servo is off.
12. SETPOINT LOCAL/REMOTE - Used to select whether the setpoint command comes from the
front panel knob or from an external remote analog 0-10 Vdc command.