OTT PLS - Carrying out Maintenance Work

7 Carrying out maintenance work
The high-quality design of the OTT PLS makes regular cleaning work unnecessary.
Even a thin build-up of deposits on the measuring cell will not appreciably affect
the measurement results.
If very heavy contamination occurs at the station due to algae, mud, vegetation or
sediment, the pressure probe should be checked from time to time. For example,
imprecise or implausible measured values may indicate a "blocked" measuring
cell. If necessary, the pressure probe can be cleaned easily.
How to clean the pressure probe
䡵 Uninstall OTT PLS (see Chapter 5).
䡵 Remove the black protective cap.
䡵 Clean the measuring cell carefully using a brush (hard bristles). Lime scale
deposits can be removed using a common household scale remover. Make sure
to follow the use and safety instructions of the scale remover!
䡵 Rinse the pressure probe thoroughly with clear water!
䡵 Reattach the black protective cap.
䡵 Reinstall OTT PLS (see Chapter 5).
䡵 Specifying measured values, comparing with a reference value (staff gauge,
contact gauge) and correcting as necessary (enter reference or offset value or
via scaling function of the datalogger attached).
Black
protective cap
Pressure sensitive
measuring cell membrane
Pressure probe
OTT PLS
Fig. 8: Cleaning the pressure probe.
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