Detecting whether a device is currently running

Hi Robin,

thanks for thinking along. The scanner does not clamp the negative holder while scanning or something.
Because the scanning takes quite some time and is a bit dependent on the type of scan, i thought it would be nice to have a feedback loop with the controller so it works reliably and efficient.

I just came across a ACS712 5A current sensing module. I think putting this between the poweradapter and scanner is nice because I can sense the current consumption over time. The circuit that is sensed and the circuit connected to the Arduino are isolated so that could work nicely.

Any experience/thoughts on this approach?