Is there a trouble shooting document for the CL10 when it reads ( ---- )?

Document ID

Document ID TE5030

Published Date

Published Date 21/01/2019
Is there a trouble shooting document for the CL10 when it reads ( ---- )?
Steps to trouble shoot CL10 with (---) on display.
Steps to trouble shoot CL10 with (---) on the display:
  1. For a new installation verify how long it has been installed?
    1. If less than overnight must let it run overnight in chlorinated sample.  It takes that long, at least, to condition the sensor itself.
  2. What is temp of process?   Electrolyte will last 2-3 months @ and >25 C or 1 month @ and >30 C.  Indicates need for more frequent electrolyte replacement.
  3. Try electrical tests
    1. Cycle power
    2. Disconnect and reconnect sensor
  4. Inspect LEDs on top of Chlorine sensor.  See page 7 in manual for explanation.  We want to see green on only.  Orange indicates error condition.  If you see green and orange sensor needs to be replaced.  LEDs can be challenging to see.  Look down from top of sensor while covering to fend off ambient light.
  5. Check mV (Menu>>Sensor Setup>>Diag/Test>>Signals) if positive that is a problem - we should see negative.  This just reinforces the (---) reading.
  6. Replace Electrolyte – see page 10 in manual for detailed pictures.  Note: bubbles are a problem and are easy to introduce.  Triple check that there are no bubbles.  Also, for free residual analyser (CLF10sc), see step #4 (page 11 in manual) which shows that you need to put electrolyte in cap.  No electrolyte in cap has caused (---).  Polishing should not be required– more likely after 1 year of operation.  It cannot hurt to polish but it’s usually not necessary.  Likewise membrane should last at least half a year and up to 1 year.
  7. If customer provides a specific residual check what method they are using for verification – must use US EPA 334.0
  8. Visually inspect electrode – see photos below for more info.  The problem with the sensors in these pictures was a RAW mV value that stayed positive after conditioning (leading to (---) on display). This first showed up after a calibration was preformed. The sensor would calibrate and then steadily drop to [---] after several minutes.
    This picture is showing the defect in the cathode coating on the CLF10. Notice that the coating is not uniform. This could be the cause of the positive mV readings.

    The anode of the sensor has large pit/chip in the center. This is the most likely cause of the positive RAW mV value.

    Picture showing the anodes pit and the cathodes uneven coating.