Introduction 1
Operating Guide 19
Status lights
The status lights provide a basic look at what is currently
happening inside the Agilent 7890A GC.
A lit LED on the status board indicates:
• The current progress of a run (Pre Run, Post Run, and
Run).
• Items that may require attention (Rate, Not Ready,
Service Due, and Run Log).
• The GC is controlled by an Agilent data system
(Remote).
• The GC is programmed for events to occur at specified
times (Clock Table).
• The GC is in gas saver mode (Gas Saver).
Beeping instrument
A series of warning beeps sound if the GC encounters a
problem. For example, a series of beeps sound if the front
inlet gas flow cannot reach setpoint. The message Front inlet
flow shutdown is briefly displayed. The flow shuts down after
2 minutes. Press [Clear] to stop the beeping.
A continuous beep sounds if a hydrogen flow is shut down
or a thermal shutdown occurs. Press [Clear] to stop the beep.
One beep sounds for other types of faults, warnings, and
shutdowns. A single beep means that a problem exists, but
the problem will not prevent the GC from executing the run.
The GC will emit one beep and display a message. The GC
can start the run and the warning disappears when a run
starts.