3
MODEL EDS880/1 TROUBLESHOOTING
PROBLEM PROBABLE CAUSE SOLUTION
Off-scale reading Wiring is wrong. Verify wiring in plug and at analyzer.
Temperature element is open or shorted. Check temperature element for open or
shorts. See Figure 3.
Sensor is not in process stream. Be sure sensor is completely submerged in
process stream.
Sensor is defective. Perform isolation checks. See Figure 4.
Noisy reading Sensor is improperly installed in process Be sure sensor is completely submerged
stream. in process stream.
Reading seems wrong (lower Bubbles trapped in sensor. Be sure sensor is properly oriented in
or higher than expected) pipe. See Figure 1.
Wrong temperature correction algorithm. Check that temperature correction is
appropriate for the sample. See analyzer
manual for more information.
Wrong cell constant. Verify that the correct cell constant has
been entered in the analyzer and that the
cell constant is appropriate for the conductivity
of the sample. See analyzer manual.
Sluggish response Electrodes are fouled. Clean electrodes.
Sensor is installed in dead area in piping. Move sensor to a location more
representative of the process liquid.
TROUBLESHOOTING
CLEANING THE SENSOR
Use a warm detergent solution and a soft brush or pipe cleaner to remove oil and scale. Isopropyl alcohol
(rubbing alcohol) can also be used to remove oily films. Avoid using acids to clean conductivity sensors.
FIGURE 3. Checking the RTD
Disconnect leads and measure resistances between the
yellow and blue leads. The resistance at room temperature should be close to 1100 Ω.
FIGURE 4. Checking Continuity and Leakage
Disconnect the coax braid and coax conductor leads and
measure resistance and continuity as shown. Sensor must
be dry when checking resistance between leads.