Walchem WebMaster ONE Instruction Manual page 166

ORP Low Alarm
This error message indicates the ORP reading is below the user-programmed maximum allowable
value.
Possible Causes
The programmed value is too close to the
ORP set point.
Chemical supply empty.
Faulty ORP electrode.
Control direction set incorrectly.
Faulty metering pump/brominator solenoid
valve.
Metering pump is siphoning.
Blown fuse.
Faulty control device wiring.
Faulty ORP output relay.
Corrective Actions
Go to the ORP Input Page and make sure
that the Low Alarm Limit is at least 50 mV
below the set point.
Replenish chemical supply.
Clean and calibrate the ORP electrode as
described in Section 7.4 above. If the
calibration fails, refer to ORP Calibration
Failure troubleshooting above.
For oxidizer feed the control direction should
be "force higher", for reducer "force lower".
Go to the ORP Output Page and make sure that
the correct control direction is selected.
Repair or replace the metering pump/solenoid
valve.
Repair or install an anti-siphon valve.
Replace fuse (F2 or F3).
Correct wiring.
Replace the relay board.
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