5.1 Installation type A: fixing the pressure probe into a protec-
tive device
In flowing waters or waterways with a swell, the pressure probe must be fixed.
With strong currents (> 0.5 … 1 m/s) the hydrodynamic influences of the station
have to be considered in the installation. Depending on the version and mounting
of the individual components, overpressure or negative pressure can arise that can
affect the measurement result.
■
Determine the minimum and maximum water level at your station (e.g. staff
gauge, contact gauge). Use both values to specify the probe position. The fol-
lowing conditions must be fulfilled:
– position the probe below the minimum water level if possible;
– difference between max. water level and position of the probe < measuring
range of the probe.
■
Fix the pressure probe according to your individual requirements in a protec-
tive device, as shown in Fig. 2 for example.
Note:
The fine setting of the probe position is carried out, for example, by entering
a reference or offset value (see Chapter 6, "Configuring/testing the OTT PLS 500")
or using a scaling function of the data logger connected.
Fig. 2: Installation example of the
OTT PLS 500 in open waterways.
With waterways with currents or swell, a
fixing pin is used to securely fasten the
probe.
Push the fixing pin through the holes in the
black protective cap.
Plastic protective tube
Fixing pin
Protective cap
OTT PLS 500
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