Hach Chlorine Sensor User Manual page 7

Sensor assembly
C A U T I O N
The electrolyte contains potassium halide and buffer to adjust acidity. Read the
MSDS sheet before opening the electrolyte bottle.
The sensor must be assembled before it can be installed in the chlorine
flow cell. Assembly consists of removing the membrane cap, filling the
membrane cap with electrolyte and putting the membrane cap on to the
electrode shaft.
Before assembling the sensor, read these precautions:
• Do not touch the electrodes and keep the electrodes clean. Do not
remove the layer on the electrodes.
• Lift up the rubber band that covers the vent hole marked "M48" on the
membrane cap before removing the membrane cap. The vent allows
air to come into the membrane cap. The membrane will be destroyed
if the vent is covered when the membrane cap is removed, because
vacuum will build up in the membrane cap.
• Do not remove the metallic membrane holder from the cap as this will
damage the membrane.
• Always put the membrane cap on a clean, non-absorbent surface.
• Do not shake the electrolyte bottle as shaking the bottle creates
bubbles. After the electrolyte bottle is opened, store the bottle up side
down.
• Make sure that there are as few bubbles in the electrolyte as possible
when filling the membrane cap with electrolyte. Too many bubbles will
decrease sensor performance.
• Do not close the vent hole marked "M48" in the membrane cap with
your finger when the membrane cap is put on to prevent excess
electrolyte from escaping through the vent. The membrane will be
damaged if the excess electrolyte can not escape. Gently clean off
any electrolyte on the outside of the sensor with a clean, dry cloth or
paper. Make sure not to touch the membrane.
• Make sure the membrane cap is completely put on up to the stop. The
first resistance comes from the O-ring seal, but continue to put on the
cap until the cap hits the electrode shaft.
Assemble the chlorine sensor
English 7