Campbell Scientific OBS-3+ and OBS300 Suspended Solids and Turbidity Monitors - Manual (Page 32)

OBS-3+ and OBS300 Suspended Solids and Turbidity Monitors
TABLE 9-1. Troubleshooting Chart
Fault Cause of Fault Remedy
Fails finger wave test No power, dead battery Replace battery and reconnect wires
MCIL-5 plug not fully seated Disconnect and reinsert plug.
Sensor broken Visually inspect for cracks. Return
the sensor to manufacturer if cracks
are found.
Electronic failure. Units draws less than 11
mA or more than 40 mA.
Return the sensor to manufacturer.
Fails shake test Sensor leaked Return the sensor to manufacturer.
Fails calibration check Aging of light source causes it to get dimmer
with time.
Recalibrate (see Section 8,
Calibration)
10. Maintenance
There are no user-serviceable parts inside the sensor
housing. Do not remove the sensor or connector from
the pressure housing. This will void the warranty and
could cause a leak.
The most important maintenance item is keeping the window clean. A
Scotch-Brite scouring pad works well for most types of window fouling.
First wet the pad and then place it on a counter with a plastic-laminate top so
that the side of the pad is aligned with the edge of the counter. Work the
window of the OBS sensor back and forth on the pad until it is clean while
removing as little epoxy as possible. If encrusting organisms such as barnacles
or tube worms have attached to the sensor, it will have to be gently scraped
with a flexible knife blade prior to using the pad. Some applications will result
in pitting of the sensor face. Pits can be removed with abrasive cloth. Polish
the sensor window as follows:
1. Tape a strip of 400 grit wet-or-dry abrasive cloth to the edge of a
counter (see above).
2. Add a few drops of water to the abrasive and work the sensor window
in smooth one-way strokes on the cloth using the counter edge as a
guide.
3. Continue until the sensor is shiny and pit free.
It is important to remove as little epoxy as possible.
Do not use solvents such as MEK, toluene, acetone, or
trichloroethylene on OBS sensors.
WARNING
NOTE
WARNING
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