mdc10.50 It helps if you take the time to carefully read the published specs first. If your question is not mentioned or documented it usually means the machine is NOT capable of doing so. That’s the case here. It CANNOT measure wattage… by the way it can only measure AC current on the clamp NO DC

mdc10.50 Batterybox -or- alternate PWR supply

mdc10.50 IF it’s recurring at regular 1min intervals, perhaps it may proof useful to check the condensators soldering to the PCB and -or- possible influence by near short circuiting with other parts. I.e. bend them to another position. IF this does not work, just to make sure, move the Geiger teller to another location a couple of km’s away and check again. You never know if it accidentally does register correct.... Than you have an interesting case to solve =:)