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Table 20 - PIC 5 – QUICK TEST LIST
5.9.1 Cooler and condenser pressure transducer and waterside flow device calibration
(Waterside Device Optional with IOB Inputs Available) — Calibration can be checked by comparing the pressure
readings from the transducer to an accurate refrigeration gage reading. The transducer can be checked and
calibrated at 2 pressure points.
These calibration points are 0 psig (0 kPa) and between 10 psig (68.9 kPa) - 30 psig (206.8 kPa). To calibrate
these transducers:
1. Shut down the compressor and the cooler and condenser pumps.
NOTE: There should be no flow through the heat exchangers.
2. Disconnect the transducer in question from its Schrader fitting for cooler or condenser transducer calibration.
For pump pressure or bearing pressure or flow device calibration keep transducer in place.
NOTE: If the cooler or condenser vessels are at 0 psig (0 kPa) atmospheric pressure, the transducers can be
calibrated for zero without removing the transducer from the vessel.
3. Access the PRESSURE screen from the Main Menu and view the particular transducer reading (the cooler
pressure, condenser pressure, economizer pressure, pump inlet pressure, pump outlet pressure, bearing inlet
pressure, bearing outlet pressure). To calibrate a device, view the particular reading on the screen. It should read
0 kPa). If the reading is not 0 kPa, but within 35 kPa, the value may be set to zero while the appropriate
transducer parameter is highlighted. The value will now go to zero. No high end calibration is necessary for REF
PUMP DELTA P or flow devices. If the transducer value is not within the calibration range, the transducer will
return to the original reading. If the pressure is within the allowed range (noted above), check the voltage ratio of
the transducer. To obtain the voltage ratio, divide the voltage (dc) input from the transducer by the supply voltage
signal (See Maintenance Others in Maintenance Menu) or measure across the positive (+ red) and negative (–
black) leads of the transducer. The voltage ratio must be between 0.80 and 0.11 for the software to allow
calibration. Rotate the waterside flow pressure device from the inlet nozzle to the outlet nozzle and repeat this
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