3 Phase outlet, one phase equipment.

[Dewayne Reding]

Dealing with a three phase 220V outlet, and single phase 220V tools. It has a blue-white-black-and a green ground wire. I do not want to modify the buildings wiring as we need the 3 phase capability. Can I make a pigtail drop cord to power the single phase tools? If so, which wire should I lose?

And if this is the least bit potentially unsafe, tell my that and I won't do it.

[Wayne Gauthier]

Call your power company and get someone out there to give you advice.


Wayne

[Kyle Kraft]

I'm not an electrician. If you have 220 across any 2 legs, then you should be able to drop a leg and have 220 single phase. The only problem I can see would be if you ran a whole bunch of machines this way, and dropped the same leg on each one, you may cause an imbalance in the force!:rolleyes:

I'm referring to the electrical force, not the Star Wars force.

[Bill Brady]

You can use two phases and the ground for your single phase device. You can connect a 240 volt device with no problem. You would have to watch connecting a new 120 volt circuit.

There is probably not going to be a problem with uneven loading, you would have to run a large number of single phase equipment before this would be a problem.

If you have a 120/208 volt three phase service there is not a problem. No problem with 120 or 208 (240) volt circuits.

If you have a 120/240 volt three phase service y ou will need to watch for the high leg. The voltage on this phase will run high so you can not use this for a 120 volt circuit.

[Rick Christopherson]

The existance of an un-labelled white can be confusing, as this signifies a grounded conductor as per NEC. So the quick answer to your question is to use the black and blue wires and the bare chassis ground.

The white may be a hot conductor, but it may also be a neutral, but since you don't need it, then it shouldn't matter as long as you don't use it.

You don't need to worry about the comment on the high leg because this only relates to its voltage with respect to neutral or ground, and your 240 volt tool does not use neutral. All phase conductors will have the same voltage phase-to-phase. (It is a valid comment however, but it just applies to 120 volt circuits.)

If this is a 120/208 volt balanced 3-phase, then your motors will run with reduced power.

[Dewayne Reding]

Thanks everyone. The blue and black leg do give us our 240 so we'll make the dropcord and try it out. Only planning to run one tool at a time. (A tablesaw, steamcleaner and a smallish TIG welder.