Shop Wiring Question

[BanduraMaker]

I'm getting my first CNC machine in a week or so and I'll be using a spindle with VFD. The VFD I'm getting is a 240v model so I'll have to add an outlet somewhere in the shop for it.

So, what I'd like to do is run a 20A circuit with an outlet where the machine will be. On the machine itself, I'm thinking it would be cool if there was a single 240v plug that powered the whole machine, including the computer and any other 120v stuff I have on there (i.e. one cable & plug that powered up the whole system).

The idea would be to run the 240 to the VFD and split off one leg for a 120v outlet (or possibly both legs for 2 outlets) in the junction box on the machine. The spindle I'm getting is only 1.5hp so I don't think I'll be over loading anything.

I can see problems with the fusing of such a setup. I know that 20A 120v outlets are available but I have this feeling I missing something here.

Does anyone have any suggestions on how this could be done properly or should I just stop trying to be clever and run two lines to power the machine, a 240 and a 120?

[Al_The_Man]

The Stove type power receptacle could be used, these are 4 pin for 2/240v, neutral and ground.
You should by rights supply the right fusing in the machine enclosure for each control circuit.
Al.

[ger21]

If you do like Al says, like a stove or dryer, use a 20amp 240V breaker. Get the 4 conductor wire (red-black-white-green) to wire to the machine. Red and black go to the breaker, and the VFD. Then use the black and white(neutral) for your 110V.

Or just run them separate.

[S3MIH3MI]

I would suggest you get some 10/3 (drier cable) and a 6 or 8 circuit pony panel.
Then feed the panel with a 30 amp breaker. You will have 120/240 at the machine.
Now you can give 20 amps the CNC Machine and 2 15 amp breakers for whatever.

Main ----------30 A --------- 6 Circuit ------------- 20 A 240 Volt CNC
Panel ---------3 wire --------- Pony ----------------15 A 120 Volt
------------------------------ Panel ----------------15 A 120 Volt

[ger21]

Much better idea.

[ger21]

If this is in your basement (I think), then just running the separate circuits is probably a cheaper option than adding a sub panel.

[S3MIH3MI]

I agree. If it's close to the main Panel then run what you need directly.

[Al_The_Man]

I would say it depends on whether the machine has an enclosure on already or if it is a build from scratch, the OP just mentioned it was a CNC machine?
It is always preferable to have one power source and one disconnect at the machine, if it is practical.
Al.

[BanduraMaker]

Originally Posted by S3MIH3MI I would suggest you get some 10/3 (drier cable) and a 6 or 8 circuit pony panel. Then feed the panel with a 30 amp breaker. You will have 120/240 at the machine. Now you can give 20 amps the CNC Machine and 2 15 amp breakers for whatever. Main ----------30 A --------- 6 Circuit ------------- 20 A 240 Volt CNC Panel ---------3 wire --------- Pony ----------------15 A 120 Volt ------------------------------ Panel ----------------15 A 120 Volt

Yes, I had kind of a similar thought. This might be the way to go. Adds some cost though for the poney panel. I looked at home despot today for inline breakers but they didn't have any. Found some online though.

p.s. the machine is an Xzero so there's a bit of work to do as far as electrics go. I'm getting a VFD, powersupply and Gecko 540 to run the thing. Bench/stand will be home made so I'd like to make sort of an integrated thing.