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6.0
MAINTENANCE
The controller itself requires very little maintenance. Wipe with a damp cloth. Do not spray down the
controller unless the enclosure door is closed and latched.
6.1
Sensor Cleaning
NOTE: The controller must be recalibrated after cleaning the sensor.
Frequency
The sensor should be cleaned periodically. The frequency required will vary by installation. In a new
installation, it is recommended that the sensor be cleaned after two weeks of service. To determine how
often the sensor must be cleaned, follow the procedure below.
1.
Read and record the conductivity.
2.
Remove, clean and replace the conductivity sensor.
3.
Read conductivity and compare with the reading in step 1 above.
If the variance in readings is greater than the accuracy you require, increase the frequency of sensor
cleaning. If it is less than the accuracy you require, the sensor was not dirty and can be cleaned less
often.
Cleaning Procedure
An accumulation of dirt, debris or scale on the sensor can affect the accuracy and the thermal time
constant. This accumulation should be removed periodically. This can be accomplished by scrubbing
with a toothbrush or stiff bottlebrush. Soap or hand cleaner may help. A mild acid solution will remove
scale. Harsh abrasives should be avoided. Rinse the sensor thoroughly before returning to service.
6.2
Replacing the Fuse Protecting Powered Relays
The fuse on the circuit board is located at the back of the controller enclosure under the plastic safety
cover. Gently remove the old fuse from its retaining clip and discard. Press the new fuse into the clip,
secure the front panel of the controller and return power to the unit.
Warning: Use of non-approved fuses can affect product safety. Use 5 x 20 mm, 6A 250V fuses only.
CAUTION: Disconnect power to the controller before opening front panel!
