6
263X Series Chlorine Electrodes
10. Troubleshooting
Problem
Possible Causes
Remedies
Sensor cannot be calibrated.
Output is higher than DPD test
(out of range).
Sensor conditioning time too short
Condition for 4 hours minimum prior to initial
calibration
Interference from contaminants
See technical data
Membrane cap damaged
Replace cap and recondition
DPD chemicals bad
Use fresh reagents
pH outside of working range
See technical data
Sensor cannot be calibrated.
Output is lower than DPD test.
Sensor conditioning time too short
Condition for 4 hours minimum prior to initial
calibration
Chlorine content too low
DPD value must be greater than 0.5 ppm to
calibrate
Low
fl
ow rate
Check to make sure
fl
ow rate is suf
fi
cient
Air bubbles on electrode membrane
Inspect visually. Tap to remove bubbles. Mount
at an angle.
Low or no electrolyte in electrode
Fill electrode with electrolyte
Organic chlorination agents present in water
See technical data
Surfactants in water
Remove surfactants and replace cap
Membrane cap coated
Clean or replace membrane cap
Membrane cap loose
Tighten or replace membrane cap
pH outside working range.
See technical data
Sensor output very low
Sensor conditioning time too short
Condition for 4 hours minimum prior to initial
calibration
Chlorine content too low
Add chlorine to validate
Only bound chlorine present. No free chlorine
Check for chloramine with appropriate DPD test
Electrode not making good contact with electronics Inspect and reconnect
Unstable output from sensor
Air bubbles on electrode membrane
Inspect visually. Tap to remove bubbles. Mount
at an angle.
Membrane damaged
Replace membrane. Condition sensor for at
least 2 hours and recalibrate.
Electrode not making good contact with electronics Inspect and reconnect
Non-sensor problem
Check 3-2650 Electronics connection to
electrode (see 3-2650 manual for instructions).
Make sure connections are dry. Check
instrument hookup.
Transmitter error messages related to calibration are detailed in the Signet 8630 Chlorine Transmitter operation manual.