Zero Adjustment; Adjusting The Atmospheric Pressure Sensor - Instrutech Busy Bee PCM301 User Manual

Instruction Manual
The operational characteristic curve of the gauge may change due to contamination and extended period of use.
Periodically check the zero and adjust it if necessary.

4.4.4 Zero adjustment

• For adjusting the zero, operate the gauge under the same constant ambient conditions and in the same
normal mounting orientation.
 If you are using a seal with centering ring and filter, check that they are clean or replace them if necessary.
 Evacuate the vacuum system to a pressure less than 7.6 X 10
 Press the <ADJ> button with a pin and the HV (zero) adjustment is carried out (duration 5 seconds).
If the pressure value 3.8×10
adjustment has been successful. Otherwise, repeat the adjustment procedure.
Note: No ATM adjustment is required for the PCM301.

4.4.5 Adjusting the Atmospheric Pressure Sensor

If you have ordered the ATM setpoint option, the atmospheric pressure around the gauge is measured by a
separate atmospheric pressure sensor built into the electronics unit of the gauge. The atmospheric pressure
sensor can be calibrated against the capacitance diaphragm sensor in the gauge. The gauge electronics
compares the output signals of the two sensors and carries out the necessary adjustments to the atmospheric
pressure sensor signal.
The adjustment of the atmospheric pressure sensor can only be carried out via the diagnostic port.
InstruTech
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Torr is output at the measurement value output or on the LCD display, the
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Torr and wait at least 2 minutes.
PCM301 Busy Bee
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