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negative injection temperature
Posted: Thu Jun 25, 2009 2:28 pm
by vestelshirley
I have an Agilent 5890(II) that registers a negative 200 injection temperature. Fuses are fine. Any suggestions?
Posted: Thu Jun 25, 2009 2:32 pm
by berti
Short circuit on the thermocouple.
When the temperature is above 800 the thermocouple burned.
If the temperature is -200 the cable of the thermocouple is in short.
Posted: Mon Jun 29, 2009 3:40 pm
by Ron
The temperature sensor is actually an RTD or PRT, whichever term you prefer, and these are mechanically more fragile than a thermocouple. The temperature sensor can be replaced, but the platinum leads are very fragile and great care must be taken while replacing the sensor to avoid breaking or shorting out the leads. A replacement injection port from a third party vendor is probably the best way to solve this problem.
A less likely but possible problem is a bad connection at the board, or a bad board.
Posted: Thu Jul 02, 2009 5:16 pm
by AICMM
Vestel,
You can buy replacement RTDs for 5890s from Restek. Just the RTD and not the whole sensor assembly the way Agilent would sell it (for much more.) You have to feel comfortable getting into the guts of the GC but it is really pretty straight forward thing to do.
Best regards.