Thyracont VSL53D, Руководство по эксплуатации

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5.7 Readjustment
The transducer is adjusted ex works with 24 V voltage supply in upright position,
flange to the bottom.
Other orientation, operation under different climatic conditions, extreme tempera-
ture changes, ageing or contamination can result in the need for readjustment of
the sensors.
Adjust High (AH)
Adjustment of Pirani sensor at atmosphere pressure. Further the ambient pressu-
re sensor is aligned with the internal piezo sensor so that relative pressure is set
to zero.
Adjust High (AH[p])
Adjustment of piezo and Pirani sensor at atmosphere pressure. A reference pres-
sure p will be required!
Adjust Low (AL)
Adjustment of piezo and Pirani sensor at zero pressure. For this purpose actual
pressure must be less than 5.0x10
-5
mbar. The ambient pressure sensor will not
be affected.
Adjust Low (AL[p])
It is also possible to adjust the Pirani sensor at a certain reference pressure in the
range 1.0x10
-4
... 1.0x10
-1
mbar. Command AL then has to be transmitted together
with the pressure value p as reference pressure. This can be beneficial, if a suita-
bly low pressure for zero adjustment cannot be applied.
To achieve optimum results of the adjustment we recommend to
consider a warm-up of at least 10 minutes at the appropriate cali-
bration pressure before any adjustment.
5.8 Sensor Parameters
Sensor Transition (ST)
By default the VSL performs a continuous transition between Pirani and piezo ran-
ge whereupon an assimilation of the sensor signals is carried out.
In order to adapt the performance of the transducer to the requirements of the
vacuum process the following options can be configured by means of parameter
»Sensor Transition« (ST):
VSL-RS485-200116