Originally Posted by
George Yetka
Malcolm I believe that measures KW usage. A clamp meter can show you amp usage while the tool is running but you would need to clamp each hot lead that goes to any particular tool. If you have a sub panel this would be easier.
The easier thing to do is calculate all major draws in the house based on equipment rating for running amps and estimate the smaller stuff add that all up and figure out what worst case draw on the house would be and figure out from there what worst case in the shop would be(compressor/dust collector/table saw/lighting)
Adding those together you should be safe.
Worst case would be if you had electric (dryer/stove/electric heat).