LEYBOLD THERMOVAC TTR 101 N, Руководство по эксплуатации

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25 300544655_002_C1 - 11/2016 - © Leybold
6.2
Vacuum-zero adjustments and setpoint adjustments
For transmitter versions with RS232 digital communication interface (P/N: 230366V02) it is possible to make
vacuum-zero (Zero) adjustments and setpoint adjustments using the RS232 digital communication interface. Refer
to Communication Protocol 300544663 for further details.
For transmitter versions with EtherCAT digital communication interface (P/N: 230702V02) it is possible to make
vacuum-zero (Zero) adjustments and setpoint adjustments using the digital communication interface. Refer to
Communication Protocol 300544664 for further details.
Setpoint adjustments with the user switch can only be performed for transmitters with P/N: 230352V02,
230353V02, 230356V02.
Zero adjustment before operation is recommended to obtain best measurement performance in the lowest part of
the measuring range. Vacuum-zero adjustment is not required for measurements above 5x10
-4
mbar. However,
drift can occur over time and periodic vacuum-zero adjustments are then recommended to optimize measurement
performance.
MEMS Pirani-sensor vacuum-zero (Zero) 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 (only possible
by using the serial interface). 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 User switch
It is possible to perform vacuum-zero adjustments (Zero) of the MEMS Pirani-sensor by using the user
switch. See chapter 6.3.

By using Serial interface
For transmitter versions with a digital communication interface (P/N: 230366V02 (RS232) and P/N:
230702V02 (EtherCAT)) it is possible to make vacuum-zero and full-scale (Zero/FS) adjustments using the
digital communication interface. Refer to Communication Protocol 300544663 (RS232) and 300544664
(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.
Attention
!
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Attention
!
!