Evoqua Wallace & Tiernan Depolox 3 plus, Manual

Page: 90 / 157

WT.050.560.001.UA.IM.0714 76
Depolox
®
3 plus ReSIDUAl ANAlYZeR
eVoQUA W3T140188
Error in Membrane Sensor for Total Chlorine TC1
Trouble-shoot and debug if the measuring signal is too low or irregular:
1. Remove air bubbles on the membrane (e.g. tap the inflow mating con-
nector); air bubbles prevent the chlorine from diffusing through the
membrane and distort the measurement.
NOTE: Air bubbles on the remaining parts of the sensor are normal after
initial commissioning or restarting; they disapate after one or two days.
2. Replenish electrolyte.
3. Open membrane sensor. To do this, push the elastomer seal to one side
to permit the inflow of air and unscrew the membrane cap.
4. Pour out the electrolyte.
5. Wash the electrode finger and the membrane cap with clean (distilled)
water and allow to dry in a dust-free place.
For further procedure, see “Commissioning the membrane sensor for
total chlorine TC1”.
If the sensor’s measuring signal is still too low or irregular, a new membrane
cap must be used. Thereafter, the measuring cell requires one to two hours
before it can be calibrated.
WARNING: DO NOT TOUCH THE REFERENCE ELECTRODE! BEFORE UN-
SCREWING THE MEMBRANE CAP, REMOVE THE ELASTOMER SEAL TO AL-
LOW AIR INTO THE VENT HOLE. NOT DOING THIS WILL CAUSE A VACUUM
TO OCCUR WHICH WILL DAMAGE THE MEMBRANE WHEN UNSCREWING
THE CAP. DO NOT REMOVE THE yELLOW-GREy LAyER ON THE REFERENCE
ELECTRODE.
NOTE: It is important that the membrane is in the direct sample water flow.
Because of this the flow-through assembly has a special form where the
sensor fits in.
!