Quote Originally Posted by Rangeball
If you know the amp rating of a particular motor, can you calculate the cost just from that?

What's the forumula you'd use?

I have a 12 amp motor, run it 24/7, and looking at my last bill I pay $.083 per KWH.
KWH is approximately (Amps X Volts divided by 1000) X Hours. At max current, your motor would use 12AX120V=1440W Dividing by 1000 gives 1.44KW X 24Hours= 34.56KWH per day, so at $0.083 per KWH, you are using $2.86 worth of electricity a day, or roughly $86 per month. Double that if that is a 220 motor.

The plate current is max, and you probably aren't using that. The only way to know how much current you are using is to measure it.