On PdM route it starts OK w/1 V/g sens (normal one I use on slow sleeve brgs) and takes ~3 readings, then goes to 'bad sensor'. Switching a bunch and it may take a few good readings and then back to 'bad'. Now I've taken it to 'off route' mode and it looks OK.

Any thoughts?

Sam,

In the measurement point setup,make sure that ICP Power is ON, Lowest and Highest Valid Signal Level is set appropriate. Exceeding either of these two limits will give the bad sensor warning. Some high sensitivity accelerometers take a while to power up, so you could try repeating a measurement to see if signal is stable.

Walt

Flaky cable/connector that makes supply to the transducer go off irregular and make bias voltage and signal flip hi / lo? Olov

Ususally ends up being a bad cable when this happens to me.

I think Oli is correct and it's a cable that 'comes and goes'. I'm using a sens of 1.010 V/g and therefore let the transducer discharge and then allow extra settling time - all techs have instruction to 'roll-on' the transducer gently and all are familar with procedures. Naturally timing and switching to various transducers with such an intermitten problem in an environment (union) where I can't touch DMM's and do testing is frustrating.

Thanks to all for the feedback and help - it is appreciated.