Calibrating The Pcm Interface - Agilent Technologies Agilent 7890 Series Maintenance Manual

Calibrating the PCM Interface

Maintaining Your GC
The interface's flow module contains a pressure sensor that
must be zeroed after it is installed on the GC. Calibration
ensures an accurate interface pressure display.
Do not connect the carrier gas to the flow module until you
have zeroed the interface's pressure sensor. For more
information on zeroing the pressure sensor, refer to the
Series Advanced User
If the gas supply is connected to the GC, turn off the
1
supply at the source, then disconnect the supply line from
the PCM inlet fitting.
Turn on the GC and wait 15 minutes to allow it to reach
2
thermal equilibrium.
When the GC has reached thermal equilibrium, press
3
[Options], scroll to Calibration and press [Enter].
Scroll to the module to be zeroed and press [Enter].
4
Scroll to a zero line and press [Info]. The GC will remind
5
you of the conditions necessary for zeroing that specific
sensor.
Flow sensors. Verify that the gas is connected and flowing
(turned on).
Pressure sensors. Disconnect the gas supply line at the
back of the GC. Turning it off is not adequate; the valve
may leak.
Press [On/Yes] to zero or [Clear] to cancel.
6
Turn off the GC.
7
8 Plumb the carrier gas to the flow module.
9 Turn on the GC.
If you were calibrating the flow sensor after replacing the
PCM, check for leaks.
Maintaining the PCM
Guide.
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