Fault message in HP 5890 series II GC

[saiprasathg]

Whenever i make an online injection, i get the following error message.
FAULT: AUX TEMP RDG.

After that the GC automatically starts to cool down all the temperature zones (INJ A, INJ B,DET A, DET B and AUX).

The user manual deciphers this fault message as "an inoperative temperature sensor for the auxiliary temperature zone". But the remedial measure is not given in the manual.

Could someone help me out.

Thanks & regards,

Saiprasathg

[GasMan]

saiprasathg,

It is a long time that I have used a 5890, but I believe that this message probably means that the temperature sensor for the auxillary heated zone is defective or there is a bad connection to the sensor. What type of heated zone do you have on this 5890.

Gasman

[jwmol]

Heating temperature zones without good feedback on the actual temperature can be dangerous. Pumping hundreds of watts into an aluminium block can even cause the block to melt leading to dangerous situations.

For this reason most GC systems have a security system built in for open (temp reading will be very high) and more importantly closed (temperature reading will be very low). More sophisticated systems may even detect that when power is applied and the temperature of a heated zone does not increase that something must be wrong. Can be a bad sensor or the heater is broken.

Either way the system will shut down its high power/high voltage circuits (usually a large relay with a loud "click") to prevent more serious problems.

Time to call in the GC doctor or check the PT100 temperature sensor and/or the heating element.

Jan Willem Mol
Appplied Instruments
http://www.applied-instruments.com

[saiprasathg]

Dear Mr. Gasman & Mr. J.W.Mol

Thank you very much for your prompt advices. I found the solution to the problem. I examined the temperature sensor carefully. The temperature sensor of the AUX temperature unit was in bad contact with the actuator. So whenever the GC gets the commmand to take a sample, it starts the actuator. The actuator or the vibration caused by the actuator somehow touches the temperature sensor and results in a shortcircuit. Now i just separated the sensor cables far from the actuators.

Now the GC works. I hope this will work properly..

Thank you once again.

Regards,
saiprasathg