LEYBOLD 230070V02, Руководство по эксплуатации

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24 300544652_002_C1 - 11/2016 - © Leybold
6.2
Vacuum-zero/full-scale adjustment and setpoint adjustments
Zero adjustment before operation is recommended to obtain best measurement performance in the lowest part of
the measuring range.
Only for transmitter versions with RS232 digital communication interface (P/N: 230088V02) or EtherCAT digital
communication interface (P/N: 230089V02) it is possible to make setpoint adjustments by using the digital
communication interface. Refer to Communication Protocol 300544663 (for RS232) or Communication Protocol
300544664 (for EtherCAT) for further details.
MEMS Pirani-sensor vacuum-zero/full-scale (Zero/FS) adjustments
The vacuum-zero adjustment function changes the MEMS Pirani measurement offset at low pressure. Temporary
or permanent shift in zero offset can be caused by contamination, corrosion, electrical noise interference and
temperature.
The MEMS Pirani full scale adjustment allows the user to adjust the MEMS Pirani full scale reading. Vent the
transmitter to atmospheric pressure using the gas that corresponds to the gas calibration setup. Full scale
adjustment can only be executed with air or Nitrogen.

By using Auto vacuum-zero
The MEMS Pirani will be zero adjusted whenever the pressure measured by the cold cathode is lower than
1 x 10
-5 mbar. For applications that do not go below 1 x 10 -5 mbar the MEMS Pirani auto zero limit can be
set to higher pressure.

By using User switch
It is possible to perform vacuum-zero/full-scale adjustments (Zero/FS) of the MEMS Pirani-sensor by using
the user switch. See chapter 6.3.

By using Serial interface
For transmitter versions with RS232 digital communication interface (P/N: 230088V02) or EtherCAT digital
communication interface (P/N: 230089V02), it is possible to make vacuum-zero/full-scale (Zero/FS)
adjustments using the digital communication interface. Refer to Communication Protocol 300544663 (for
RS232) or Communication Protocol 300544664 (for EtherCAT) for further details.
To obtain best measuring performance, it is recommended that the transmitter is evacuated to a
pressure below 1×10
-5 mbar before executing zero adjustment of the MEMS Pirani sensor.
Zero adjustment of the MEMS Pirani sensor can be executed at pressures higher than 1×10
-5
mbar,
but this can cause inaccurate readings in the lower part of the measuring range.
If the pressure measured by the transmitter is higher than approximately 1x10
-2 mbar, then the zero
adjustment cannot be executed. If the zero adjustment failed, the LED-ring/LED will flash red three
times.
Zero adjustment only changes the low measuring range and will have no influence on measuring
errors in the range from 1×10
-2
mbar and above.
Full scale adjustment only changes the high measuring range and will have no influence on
measuring errors in the range below 10 mbar.
Before performing the atmospheric adjustment with the user switch, vent transmitter to Nitrogen or
air pressure of 1000 mbar. The transmitter will only accept full-scale adjustment when the pressure
readout is within 600 to 1000 mbar. Note that if the adjustment is performed at a true pressure
different from 1000 mbar, it can cause measurement deviations in the upper part of the measuring
range.
Attention
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Attention
!
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Caution
!
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