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5.0
MAINTENANCE
The Model T80 transmitter requires no periodic maintenance, except to make sure the front window is kept
clean in order to permit a clear view of the display and allow proper operation of the navigation buttons. If the
window becomes soiled, clean it using a soft damp cloth or soft tissue. To deal with more stubborn stains, a
neutral detergent or spray cleaner like Windex may be used. Never use harsh chemicals or solvents.
When you open the front cover and/or cable glands, make sure that the seals are clean and correctly fitted
when the unit is re-assembled in order to maintain the housing’s NEMA 4X weatherproof integrity against water
and water vapor.
5.1
T
OTAL
C
HLORINE
S
ENSOR
Check the measurement versus a DPD test and visually inspect the sensor at
regular intervals, at least once a month. If the membrane is visibly soiled clean it
with a jet of water or a dilute HCl solution between 1-5%. Do not clean with
detergents or solvents that would reduce the surface tension of the membrane.
5.1.1
R
EMOVING OR
R
EPLACING THE
M
EMBRANE
First,
expose the vent hole
on the cap by sliding the silicone band out of the
groove.
Failure to vent the sensor before removing the cap can destroy the
membrane.
Replace the membrane cap (PN 1000245-1) if heavily soiled or torn.
Remove the membrane cap by screwing it off of the body. Refill the new
membrane cap with electrolyte as described below and reinstall the cap on the
sensor.
5.1.2
P
OLISHING THE
C
ATHODE
Polish the cathode when re-commissioning the sensor after storage or whenever
the membrane cap is replaced. Silver from the anode deposits on the cathode
over time and must be removed. Hold the supplied blue polishing strip on your
finger tip and with the sensor held vertically, cathode facing up, gently wipe the
strip across the cathode 2-3 times. This is an abrasive cleaning and does remove
metal from the cathode shortening the sensors life. The cathode is 24 carat gold
and after polishing it should look like 24 K gold not silvery like 10 K gold.
5.1.3
R
EFILLING THE
S
ENSOR
Refill the sensor with electrolyte (PN 100246-1) every three months or sooner
depending on the chlorine level measured. The measured chlorine is reduced to
chloride inside the cell and must be periodically removed. Samples with less than 5 ppm total chlorine require
the sensor to be refilled every 3-4 months.
Lift the silicone band to Expose the vent hole
and unscrew the measuring cap from the sensor. Rinse out the
spent solution with distilled water.
Fill the cap to the bottom of the threads with the gelled electrolyte and tap it gently to dislodge any trapped
bubbles inside the cap.
Screw the sensor into the measurement cap at a 45° angle ensuring all air inside the chamber is purged through
the vent hole on the side of the cap.
When the o-ring begins to seal continue slowly tightening until it hits the stop. Seal the silicone band back over
the vent hole and rinse the purged electrolyte from the sensor body with water. The sensor is ready to use, re-
polarize the sensor for 60 minutes before calibration.