Problem
Possible Cause
Solution
No reading (1)
Insufficient conditioning.
Reading should appear within 10
mins.
No reading (2)
Electrode connection or power
supply.
Check connection/wiring.
No reading and electrode feels warm
PCB shorted or corrupted.
Replace electrode
Zero point out of specification
1. Water sample is not
chlorine free
2. Insufficient
polarization/conditioning
3. Interfering substances
cannot be cleaned
electrochemically.
1. Replace the zero chlorine
water.
2. Continue polarizing
andconditioning electrode.
3. Brush WE with polishing
strip.
Reading instable or fluctuation
1. Membrane cap fouled or
damaged.
2. Air bubbles on outside of
membranecap – especially
at center pore
3. Air bubbles inside the
membrane cap.
1. Clean or change membrane
cap.
2. Shake the electrode to
remove theair bubbles from
the center pore.
3. Shake electrode or inspect
the cap for air bubbles
Slope too low
1. Membrane cap fouled.
2. IFG deterioration.
3. Insufficient conditioning
4. Flow rate too low.
5. Erroneous DPD
standardization.
1. Clean or change membrane
cap.
2. Refill IFG.
3. Recondition the electrode.
4. Adjust flow rate into
working range.
5. Check the measurement
range of the DPD and
recalibrate.
Reading out of range
1. Chlorine content >
maximum measuring range.
2. Electrode and membrane
cap are unmatched or
improperly attached.
1. Confirm actual sample or
electrode range
specification
2. Reinstall the membrane cap
looser or slightly tighter.
Replace the membrane cap.
7. Package Include:
