Hi everyone,

I'm trying to resurrect an older Waters ZQ. A lot is going well, some isn't going well. I don't have the correct Edwards 28 that comes standard with it, so I'm using an external roughing pump that I manually turn on before trying to evacuate the unit. The turbo will come on, but floats between 12 and 20% speed for several minutes before I get a pumping failure error.

Watching the numbers, I'm wondering if the issue is with the Pirani Gauge signal. The gauge apparently reads 0V and the pressure says 10e-4 which is what it reads when it isn't plugged in. I'm sure the computer won't let it pump at full speed if it isn't getting a reading from the gauge.

I know the gauge itself works because I connected it to another MS. I'm not sure if there is a bad fuse on the board, or something more serious or maybe a bad cable (not sure if it's straight or cross over). I think there is some command to check the gauge... Rio rings a bell but I forget the exact command.

Anyone have any ideas?