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7.5 Automatic weekly pump health test.
As a preventative measure to counter pump/shaft seal seizure and to check the operational
state and health of the pump the controller performs a weekly test of the pump for a period of
approximately 10 seconds. The controller measures the full load current (FLC) the pump draws
performing two checks against hardwired values and two checks against learned FLC current
values of the pump. Test details below:
1) Measured Current is > 1 Amp
Pump Open circuit/Pump fuse
failure
Activate Fault relay/Fault LED
< 14.3 Amps for 1ph controller
< 28 Amps for 3ph controller
Pump short circuit/shaft seal
seized
Activate Fault relay/Fault LED
3) Measured Current within + 30 % of FLC
Activate Service relay/Service LED
4) Measured Current within - 30 % of FLC
Activate Service relay/Service LED
If the measured FLC fails checks 1) or 2) then the system has failed and requires immediate
attention. The Fault relay and LED are activated.
If the measured FLC fails checks 3) or 4) then the pump requires replacing or servicing, the
Service relay and LED are activated.
The time of day that the self-test is performed can be programmed at the Commissioning
stage and Re-set by the user at any time. (See the Commissioning checklist)
7.6 Manual pump health test
The Pump health can be manually tested by pressing the Test/Reset button until the pump
runs. The test is the same as the Automatic weekly pump self-test.
Press and hold the Test
button for >2 seconds
Pump runs