Can I apply power, at atmospheric pressure, to the Extorr Electronics (CCU) when it is plugged into the probe?
Sure, the unit is intended to start measuring pressure at atmosphere using the built-in Pirani gauge. The constant checks of total pressure make the Extorr virtually indestructible. The electronics may be operated at any pressure, either connected to the probe or not. No harm will come to the probe or the electronics.
