110v Light Wiring On 220v 3phase Lathe?

Uglydog

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I searched and didn't find a similar thread. I don't intend to duplicate.

I'm wiring a 220v 3ph lathe, and would like to wire in a 110v machine light without stretching any copper not needed.
Is it correct that I should be able to connect 1leg of the 110v light to one leg of the 220v wires, after I ensure that it is not the leg off the RPC?
However, the second leg would require additional copper wired normally to the panel, because wiring to the ground seems like a bad idea.

Is this accurate?
Are there better/different/safer options?

Thanks,
Daryl
MN
 
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A couple of our machines at the shop are 220 3 phase with 120 accessories. Therefore they have 5 conductor feed. 3 for the 3 phase for the 220, 1 neutral (which allows the 110 from one of the 3 phase wires) and 1 Ground. That is the best I can do for you. Someone with RPC experience will know better than I.
Pierre
 
I searched and didn't find a similar thread. I don't intend to duplicate.

I'm wiring a 220v 3ph lathe, and would like to wire in a 110v machine light without stretching any copper not needed.
Is it correct that I should be able to connect 1leg of the 110v light to one leg of the 220v wires, after I ensure that it is not the leg off the RPC?

Thanks,
Daryl
MN

Yes. You'll need to bring in the neutral. Also note that the 110V wire will need to be adequate to be protected by the circuit breaker on that circuit.
 
Yes. You'll need to bring in the neutral. Also note that the 110V wire will need to be adequate to be protected by the circuit breaker on that circuit.

I anticipated the neutral. Thanks for confirmation.
I hadn't considered that I'd need to up the gage on all the wires to match the breaker.
Makes sense....
It might be easier to run a second pair of 110v wires in the conduit (if there is room) with a 110v breaker.
Or just keep it completely separate!!

Hmmm, is it acceptable to keep things simple?

Thanks all!!
Daryl
MN
 
I anticipated the neutral. Thanks for confirmation.
I hadn't considered that I'd need to up the gage on all the wires to match the breaker.
Makes sense....
It might be easier to run a second pair of 110v wires in the conduit (if there is room) with a 110v breaker.
Or just keep it completely separate!!

Hmmm, is it acceptable to keep things simple?

Thanks all!!
Daryl
MN

You could also add a cartridge fuse in the RPC enclosure.
 
Any 3 phase equipment I've seen has a step down transformer across one leg that supplies low voltage for the control circuits (often 24v) and a tap to supply 110v for readouts and lights. If your running off a RPC you'd have to make sure that leg was the one not generated.
If you bring another wire in for neutral it would need to be switched in the main disconnect or/and main contactor.
Even 220 single phase equipment use this system to get control power and lights.

Greg
 
How about using low voltage LED lighting from a transformer that can be fed 220v.
 
I anticipated the neutral. Thanks for confirmation.
I hadn't considered that I'd need to up the gage on all the wires to match the breaker.
Makes sense....
It might be easier to run a second pair of 110v wires in the conduit (if there is room) with a 110v breaker.
Or just keep it completely separate!!

Hmmm, is it acceptable to keep things simple?

Thanks all!!
Daryl
MN
You got it now. Your easy answer for 110 circuits on a machine with no neutral leg coming in is going to be to pull a 12/2 with ground wire on its own breaker. If your wiring to the rpc isn't pulled yet, you could also pull a four wire lead to it and split your hot, neutral, and ground to create 110 before it goes into rpc. I think your separate 110 circuit from the box will come out cheaper. Good luck
 
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