Thyracont VSH87PN, Operating Instructions Manual

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5.5 Measurement Query
Measurement Range (MR):
∗
Query measurement range of the gauge
Measurement Value MV:
Query current pressure measurement
Measurement Value M1:
∗
Query current pressure measurement of the Pirani sensor
Measurement Value M3:
∗
Query current pressure measurement of the hot cathode sensor. If the hot cathode
sensor is switched off, error code »_ SEDIS« will be returned.
∗
) Not accessible via Profinet
5.6 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 Pirani sensor.
Adjust High (AH)
Adjustment of the Pirani sensor at atmosphere pressure.
Adjust Low (AL)
Adjustment of the Pirani sensor at zero pressure. For this purpose actual pressure
must be less than 5.0x10
-5
mbar.
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.
5.7 Sensor Parameters
Degas (DG)
Deposition or adsorbed gas molecules on the electrodes of the hot cathode sensor
may lead to increased degassing in ultrahigh vacuum or even cause instabilities of
the measurement signal.
VSH-Profinet-200116