Walchem WDB400 Series, Instruction Manual

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7.0 TROUBLESHOOTING
CAUTION
: Disconnect power to the controller before opening front panel!
Troubleshooting and repair of a malfunctioning controller should only be attempted by qualified personnel
using caution to ensure safety and limit unnecessary further damage. Contact the factory.
7.1 Error Messages
HIGH ALARM - (main summary screen only)
The summary screen will display an H at the right end of the bar graph if the conductivity rises above the high conductivity alarm set point.
The controller will continue to check the conductivity, and the Blowdown and/or feed outputs will be allowed to be activated.
Possible Cause Corrective Action
Dirty electrode Clean electrode (see Sect. 6.1)
Faulty solenoid valve Repair or replace solenoid valve.
Faulty electrode Evaluate (see Sect. 7.3). Check Temp display.
Improper wiring of valve or controller. Correct wiring. (see Section 3.4)
Faulty Blowdown relay Replace relay. (Consult factory.)
LOW ALARM
The summary screen will display an L at the left end of the bar graph. The controller will continue to check the conductivity and feed
inhibitor as programmed.
Possible Cause Corrective Action
Sensor disconnected Reconnect. Check cable for continuity.
Sensor dry Check tee for obstruction. Verify flow. Change location of electrode.
Solenoid valve stuck open Repair or replace solenoid valve. (Consult your distributor).
Faulty electrode Evaluate (see Section 7.3). Replace if necessary.
Improper wiring of probe Correct wiring. (see Section 3.4)
Faulty Blowdown relay Replace relay. (Consult factory.)
TEMP ERROR
This error condition will stop conductivity control. It indicates that the temperature signal from the conductivity electrode is no longer valid.
This prevents controlling based upon a false pH or conductivity reading.
Possible Cause Corrective Action
Green or white electrode wire disconnected. Reconnect.
Faulty electrode Evaluate (see Section 7.3). Replace if necessary. Revert to manual temperature
compensation by cycling power off and on.
COND ERROR
This error condition will stop conductivity control. It indicates that the conductivity signal from the electrode is no longer valid. This
prevents controlling based upon a false conductivity reading.
Possible Cause Corrective Action
Black or red electrode wire shorted. Disconnect short.
Faulty electrode Evaluate (see Section 7.3). Replace if necessary.
Faulty controller Verify via failed self-test.