FISCHER NC57, Руководство по эксплуатации

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Useful information about the calibration
If the filling levels change, the calibration can be repeated at any time. If just
one of the two filling levels changes, it is sufficient to recalibrate only the corres-
ponding value.
If you wish, you can use only part of the electrode length as the measuring dis-
tance. However, the shorter the measuring distance, the lower the precision.
The best results are achieved if the electrodes are only just wetted for the zero
point calibration and are almost but not quite fully submerged for the end point
calibration.
The output signal of the probe depends linearly on the wetting level of the elec-
trodes. The filling level is proportional to the filling volume in a cylindrical tank.
NOTICE! This simple ratio no longer applies in the case of complex tank
forms. Depending on the tank geometry, the filling level and tank content
can differ significantly.
In the case of non-conductive fluids and very short electrodes, the impact of the
stray capacitance of the environment will increase. For this reason, the probe
should be installed in the middle of the tank if possible. The further the metal
walls or metal frame from the electrodes, the lower the effect of this stray capa-
citance.
If several filling level probes lie close together, all probes can be calibrated at
the same time with an infrared remote control. However, if you want to avoid
this, it is generally sufficient to specifically target the probe to be calibrated.
Nevertheless, the safest way to proceed is to deactivate all of the other probes
for the duration of the calibration.