Pulsafeeder PULSAmatic 7120, Installation, Operation, & Maintenance Instruction

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9
12. The above adjustments are interactive. It may be necessary to repeat steps (8)
through (12) several times until the voltages stabilize. This completes coarse
adjustment
With Ratio Control (Optional Feature) – Fine Adjustment
13. With the override switch still in the “out” or manual position start the pump.
14. Set up a voltmeter for DC voltage measurement between TB2-3 (positive) and TB2-1
(common).
15. Set the control signal at the low end (0%). Move the override switch to the “in” or auto
position. The “LO” drive LED will light and the pump will automatically adjust to 0%
stroke.
16. Adjust the “LO” trim potentiometer on the circuit board to the voltage recorded in step
(6). The stroke indicator should now read 000-001 and both LED drive lights should
be off.
17. Apply a high end (100%) control signal. Allow the pump to adjust to 100% stroke.
18. With the voltmeter remaining as set up in step (14) above, adjust the “HI” trim
potentiometer to the voltage recorded in step (7). The stroke indicator should now
read 099-100 and again both drive lights should be off.
19. The above adjustments are interactive. It may be necessary to repeat steps (12)
through (16) several times until the voltages stabilize. This completes fine adjustment.
5.3 Meter Readout Calibration
This procedure trims the current output to the calibrated range of pump capacity or
stroke. Because the output is based on position of the feedback potentiometer, an input
signal is not required for adjustment.
Depending on the options ordered an analog meter will have been supplied for signal
indication. If not, an amp meter will be required to measure the output, 0-10 mA standard,
4-20 mA optional.
1. With the pump set a zero stroke, adjust the “Meter Zero” potentiometer on the circuit
board (to the left of TB-3, as shown in Figure 4) for zero (0%) meter indication or 0%
current level as applicable. Note that with 4-20 mA output the “Meter Zero” and
“Range” potentiometers will be reversed.
2. Will the pump set at full stroke; adjust the “Range” potentiometer on the circuit board
for 100% meter indication or 100% current level as applicable.
3. The above adjustments are interactive. Repeat steps (1) through (2) several times
until the meter accurately indicates both zero and full stroke settings.
5.4 Auto-Manual Calibration
This procedure trims the manual control potentiometer to the low and high ends o the
actual input control signal.
The main circuit board must be calibrated prior to this procedure.
For current type control signals, a resistor is installed across terminals of the auto-manual
switch. If present, this resistor must remain in place.