how do i check to see if I have three phase elec. wired in my shop?

Answer 1

Are you talking about a home or a commercial location? If you are at home, virtually no home in the US is wired with three-phase power.

If you are in a commercial location, an outlet for three-phase power will have three or four holes. (The fourth hole is for a ground connection.) Using a voltmeter, measure the voltage between each pair of connections. Every possible pair should give you the same reading. Then measure each of the connections to ground. Again, all three connections should have exactly the same measurement to a ground point. (I can't say exactly what the reading will be without knowing what the power company is delivering, but it will measure exactly the same for all three hot terminals.)

If you have single-phase power (which is every home in the US), you will have one connection that will be hot to ground for a 120-volt outlet, or two connections that will be hot to ground for a 240-volt outlet. In no instance should there be more than two connections hot to ground in a single-phase system.

Answer 2

Look at the outlets, you will see a definate difference. you can also read the power output on most 220-240 single and three phase outlets. It should also be seen in your panel box.

Answer 3

look on the buss bar.( where the breakers make contact with the power feed)
if there are 3 bars there, you have three phase service. if there are only 2, it's a single phase service. also if you breakers have to be bolted into the panel, you definately have three phase. they do not make a single phase panel with bolt in breakers.

Answer 4

The easiest way would be to call your supplier of electricity. Other than that an Oscilloscope would show you. With reservations, hire an electrician.