120/240VAC for mill and lathe

[danroy323]

I'm about to start the wiring of my garage. I have a metal lathe and Bridgeport mill. Both are setup to run on 240VAC single phase. At my father's garage they were plugged with 6-50 plugs (welder plug) on 30A circuits. I have lights and digital readout(well, I wish I had the DRO... but I have the lights!!) on them that run on 120VAC so I need a 120V receptacle as well. I was thinking of using a NEMA 14-30 plug and receptacle (clothes dryer plug). That way I would have a neutral wire as well and I could wire a 120V receptacle right on the machines, reducing wiring clutter between machine and wall. Is this a legal way of doing things?

Thanks,
Dan

 

[TWX]

When I was researching this same thing before going with 14-50 for my compressor I learned that dryers used to be hot-hot-neutral so that they could run 120V or 240V depending on the system in the dryer. Now many dryers are four-wire, to add the ground.

I'm pretty sure the main reason why the 14-50 setup was chosen was specific for your application.

 

[Norcal]

How large are the motors? 30A is too large to tap off for lights w/o fusing it down, but a 20A 4wire 125/250V rated locking (NEMA config. # eludes me) receptacle/plug is EZ to get.

 

[Aceman]

How large are the motors? 30A is too large to tap off for lights w/o fusing it down, but a 20A 4wire 125/250V rated locking (NEMA config. # eludes me) receptacle/plug is EZ to get.

I honestly wouldn't have a problem with it. Light fixtures are fed from 30A circuits all the time. 240.5(B)2 lets you use 14 awg taps from a 30 amp lighting circuit, not that I consider this a light fixture, but just as an example.

 

[danroy323]

Thanks guys for the answers.

The machines aren't near me so I can't check for sure but I'd say 1 or 1 1/2hp.

The only thing I see is that I'd have 30amps at the 120V outlets. Just need to be careful and limit the use of these outlets to the work lights and digital readout.

Dan

 

[Falcon67]

FWIW - when I run my lathe and mill feeds, I run a dedicated feed for each. Running a separate #12 for a 110V accessory outlet doesn't cost much of anything unless you have to go buy a 250' spool. I like to be able to power down the machines and still have accessory power close by.

If you want to self-limit the outlet use, put twist lock plugs and sockets on the 110V power outlets

 

[danroy323]

I was thinking about it, if my machines are 1 1/2hp or less I should be ok with 20 amps circuits. 20amps in the 120V receptacle would be better.