Background Energy Consumption

Cardew

I think this explanation is as good as any; noise can cause problems with unsophisticated measuring devices:

Originally Posted by Dave Fowler
I too have owl monitors. My Owl reads 0.067kW when the system has shut down for the night. I have looked at the waveform on the current sense probe at night and find it is just a mush of spikes - hardly any 50Hz (mains frequency) content. The Owl just processes the spikes and gives the erroneous reading. I would not trust the readings as being anything like accurate below 250W.

Dave F