Pcms - Agilent Technologies 8890 Operation Manual

11 Configuration

PCMs

A pressure control module (PCM) provides two channels of gas control.
To configure a PCM:
1 Select Settings > Configuration > PCMs.
2 Select the PCMs Aux Mode:
•
•
3 Select the Gas Type for channel 1, the forward-pressure control channel.
4 Select the Gas Type for the auxiliary channel (channel 2).
Channel 1 of the PCM provides forward pressure or forward flow control. It can be used to
provide column flow or pressure for valved systems, sample preparation devices, or advanced
flow devices like splitters or switches.
Channel 2, or the auxiliary channel, can only provide forward pressure regulation when
plumbed normally, or back pressure regulation when reversed. Thus, channel 2 (reversed) can
be used as a controlled leak. If the input pressure drops below setpoint, the regulator can close
down to restore it. If the input pressure rises above setpoint, the regulator can open to restore
it.
Operation Manual
Forward Pressure: Pressure is being sensed downstream from the flow proportional valve.
Back pressure: Pressure is being sensed upstream from the flow proportional valve.
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