If The Status Lamp Is Yellow And The Vacuum Pump Runs Continuously - Agilent Technologies 1100 Series Reference Manual

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Troubleshooting
Troubleshooting

If the Status Lamp is Yellow and the Vacuum Pump Runs Continuously

If the Status Lamp is Yellow and the
Vacuum Pump Runs Continuously
Before starting the following troubleshooting procedures check that all tubes
on the vacuum container, the pressure sensor, the vacuum pump and the
solenoid valve are tight and connected properly. Then follow the
troubleshooting instructions step by step to eliminate the individual parts
one after the other as the sources of the problem.
Preparing to Measure the Pressure Sensor Readings
First of all remove the top cover (see "Removing and Refitting the Top Cover"
on page 50). Use the "Overview of Internal Parts" on page 54 as a guide to
identify the individual parts.
For test purposes and for monitoring the readings of the pressure sensor
connect the auxiliary cable to the AUX output at the back of the micro
vacuum degasser. Connect a test meter to wire 1 (white) and 2 (brown) of the
auxiliary cable. When the vacuum chamber is at ambient pressure, a DC
voltage measurement across these wires will give between 1.5 and 2.7 Volts
(for pin connections see, "Auxiliary Cable" on page 72).
The voltage readings given for the various modes are rough values. All values
are set in the factory according to the vacuum level. Depending on the vacuum
sensor batch variations this will result in different voltage readings.
Regardless of the readings of the various stages no adjustment should be
performed on the degasser electronics.
Eliminate the vacuum pump as the source of the problem.
1 Disconnect the sensor tube at position 4.
2 Remove the vacuum pump and place it on the top of the vacuum chamber
3 Disconnect the solenoid valve tube at position 9.
4 Switch the degasser into continuous mode (SW1 to 1).
5 Turn ON the degasser, wait 15 seconds, then connect the sensor assembly
tube at position 9.
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