Agilent Technologies 6890 Series Service Manual page 548

Shutdown 3—Front inlet pressure shutdown
This message indicates the inlet failed to reach its setpoint in the allotted
time or cannot maintain its pressure setpoint. The inlet's flows shut off (split/
splitless inlets go to purge mode) and the instrument goes to a not ready state
until the problem is corrected and the inlet reaches the pressure setpoint.
For EPC inlets, the allotted time to reach the pressure setpoint before the
inlet shuts down varies with the type of inlet as shown in the following table.
Type of inlet
Purged packed, cool on-column
Split/splitless
Auxiliary
The following may be causing the error:
The initial gas supply pressure is too low to reach the setpoint.
Make sure that the initial gas supplies are high enough to support the
pressure and flow setpoints. The pressure at the initial supply should be
at least 5 psi (10 psi for the split/splitless inlet) greater than the desired
setpoint.
A large leak is present somewhere in the system.
Use an electronic leak detector to find leaks; correct them. Refer to
chapter 200 for the leak test procedure for your inlet. In addition to
checking the gas supply connections and the inlet, remember that the
column could be broken, which would cause a large leak.
If you are using the gas saver, make sure that the gas saver flow rate is
high enough to maintain the highest column-head pressure during a run.
The flow is too low for the column in use.
Make sure that the flow is adequate for the column you are using.
Jun 2001
Shutdown 3—Front inlet pressure shutdown
Lapse in time before shutdown
2 minutes
5.5 minutes
4 minutes
Error Codes and Internal Diagnostics
Agilent 6890 Gas Chromatograph Service Manual
Shutdowns 840
3 of 10