Agilent Technologies 6890 Series, Service Manual, Page: 532 / 867

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Jun 2001
Error Codes and Internal Diagnostics
Agilent 6890 Gas Chromatograph Service Manual
Not Ready Messages 820
Valve not ready
Valve not ready
Some valve conditions can put the GC in a not ready state.
Multiposition valve
Status message: Multiposition valve
The multiposition valve is causing the GC to be in a not ready state for one
of the following reasons:
❐
The multiposition valve is not at the setpoint position. The instrument
will be not ready until the valve reaches the setpoint.
❐
The BCD cable is missing or not plugged into the receptacle. If the cable
is missing, the valve will never become ready.
❐
The BCD setpoint is incorrect for the valve’s BCD output polarity. The
valve will most likely shutdown with Illegal Position or Not Switching
shutdown errors.
❐
If the valve is plugged or the sample is viscous, the switching time may
not allow adequate time for the valve to switch. Increase the switching
time.
24 volt valve drive
Status message: 24 V pneu valve drive
This Not Ready state indicates that the +24 V supply to the pneumatics valves
is actually less than +16.5 V. All the valves are disabled to prevent improper
operation. When the full voltage is restored, the GC will become ready.
This Not Ready state could indicate a hardware problem.
Gas sampling valve n
Status message: Gas sampling valve n
The GC is not ready because the inject time or load time has not elapsed.
❐
The GC will become ready as soon as the specified load or inject time has
passed.