Omega Engineering CDE-45P - Manual (Page 11)

Omega CDE-45P
Conductivity Sensor Part 3 –Maintenance & Troubleshooting
O&M Manual
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3.2
Troubleshooting
The first step in resolving any measurement problem is to
determine whether the trouble lies in the sensor or the
transmitter. Since measurement problems can often be
traced to surface deposits coating the electrodes, cleaning
the sensor using the method outlined in Section 3.1 should
always be the first step in any troubleshooting.
If the sensor cannot be calibrated after cleaning, perform the
following test. A multimeter will be needed.
1. Disconnect the sensor from the transmitter or junction
box.
2. Using a multimeter, verify continuity between
electrodes indicated below and the corresponding
wire colors in the cable (red, blue, green and white,
only).
3. Verify that the sensor’s temperature element (Pt1000
RTD) is functioning properly by measuring the
resistance between the sensor’s yellow and black
wires. The nominal resistance value at 25 ºC is 1097
ohms. Use the following table as a guide to the
approximate resistance value: