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Diagnostics
22
311596A
Table 3: Trips and Diagnostic Procedures
Trip
Code
Trip Description
Diagnostic
40
High System Pressure
(System pressure is higher
than the allowed maxi-
mum)
1.
Check High Pressure Alarm setting (Pr 20.09). Verify that system
desired operational pressure is lower then High Pressure Alarm setting.
2.
Check for flow restrictions (closed valves, unexpected restrictions).
3.
Check fluid supply to the pump.
4.
Check pump fluid section for proper operation (piston seals, ball
checks). Refer to pump maintenance manual for additional information.
41
Low System Pressure
(System pressure is lower
than the allowed minimum)
1.
Check Low Pressure Alarm setting (Pr 20.07). Verify that system
desired operational pressure is higher then Low Pressure Alarm setting.
2.
Check fluid level. Low fluid level will cause system to run at low pres-
sure.
3.
Check fluid supply to the pump.
4.
Check pump fluid section for proper operation (piston seals, ball
checks). Refer to pump maintenance manual for additional information.
42
No TDC (Top Dead Center
Sensor is not detected)
1.
Verify that output shaft is turning. If trip is active, enable Secure Disable,
reset the trip, and restart the pump to verify if it is running.
2.
Verify all of the wiring.
3.
Verify that sensor is operational. Remove PCB cover and monitor LED
light on a top of the sensor. The light should be normally on and it
should be turned off for only short period of time when top dead center
is reached.
43
High Motor Current
(Motor current has
exceeded the maximum for
the duration of 30 sec-
onds)
1.
Check motor calibration Pr 20.37 (UL. motor is 0 and ATEX motor is 1).
2.
Check torque on both throat-packing nuts (see lower repair-parts man-
ual 311690).
3.
Flow/Pressure combination may be set too high for a given fluid/system.
4.
Check ramp rate setting in Pr 20.02. If ramp rate is set too high consider
changing it to a lower setting.
44
Operational Envelope
(System has operated out-
side of operational window
for the duration of 30 sec-
onds)
1.
Check system pressure setting. Ensure that system pressure does not
exceed the allowed operational envelope. Refer to Operation Manual
311593 for Motor Speed and Flow Charts.
2.
Check pressure sensor calibration. If sensor needs to be recalibrated
follow instructions, page 35.