how to wire 220 basement outlets + protection

[pjtoledo]

getting ready to wire up the new lathe, in the basement.
2hp, 220 volts, 12 amp full load. manual calls for 6-15 outlet, 14 ga wire, 15a breaker. 2 hots and a ground, no neutral.
I'll probably step up to 6-20 receptacle using 12ga wire and a 20 breaker. slight overkill/planning ahead.
will run dedicated metal conduit from box to the outlet, then HD power cord.
I'll also run a separate dedicated ground from the machine to the main ground going to the water line, hard wired.

since I'll be standing on the concrete floor my concern is fault protection, what does 220 use for GFCI?

on a side note, what about the 220 clothes drier?

 

[sgtsandman]

getting ready to wire up the new lathe, in the basement.
2hp, 220 volts, 12 amp full load. manual calls for 6-15 outlet, 14 ga wire, 15a breaker. 2 hots and a ground, no neutral.
I'll probably step up to 6-20 receptacle using 12ga wire and a 20 breaker. slight overkill/planning ahead.
will run dedicated metal conduit from box to the outlet, then HD power cord.
I'll also run a separate dedicated ground from the machine to the main ground going to the water line, hard wired.

since I'll be standing on the concrete floor my concern is fault protection, what does 220 use for GFCI?

on a side note, what about the 220 clothes drier?

@Jim Oaks @Curious Hound @franklin2 any tips for pj?

Eric is a professional electrician. Jim just did a lot of wire installation to his shop, including a 220 circuit, if I remember correctly, so has recent experience. Franklin seems to have a lot of electrical knowledge swirling around in his brain pan as well. I know enough to do automotive wiring but might get you killed when it comes to 220.

 

[pjtoledo]

It's the 220 fault protection I need help with. getting enough power there to fry my arse is easy.

hell, I could just run an extension cord across the concrete floor that's covered with sharp metal chips, right?

 

[lowspeedpursuit]

GFCI breaker, no? They're just ungodly expensive.

I wouldn't oversize the breaker for a single-purpose circuit. Follow what the equipment says, unless it's obviously stupid / contradicts code.

 

[Curious Hound]

getting ready to wire up the new lathe, in the basement.
2hp, 220 volts, 12 amp full load. manual calls for 6-15 outlet, 14 ga wire, 15a breaker. 2 hots and a ground, no neutral.
I'll probably step up to 6-20 receptacle using 12ga wire and a 20 breaker. slight overkill/planning ahead.
will run dedicated metal conduit from box to the outlet, then HD power cord.
I'll also run a separate dedicated ground from the machine to the main ground going to the water line, hard wired.

since I'll be standing on the concrete floor my concern is fault protection, what does 220 use for GFCI?

on a side note, what about the 220 clothes drier?

Stick to the 6-15 receptacle and 15amp breaker. For a dedicated piece of equipment like this, code says the overcurrent orotection needs to be 125% of full load current. That's where the 15amps comes from. I would run 20amp wire in case you need to upgrade for a different piece of equipmemt in the future. But leave the breaker at 15amps. That protects the equipment in case of a short circuit. A 15amp breaker trips sooner/faster than a 20amp breaker. Therefore, fault current will not get as high before tripping and less equipment damage. GFCI is a good idea. They make 2 pole GFCI breakers.

 

[Jim Oaks]

The 14ga wire concerns me. I would think this would be at least 12ga. I wouldn't use 14ga to power anything more than lights on a 15 amp circuit.

 

[scotts90ranger]

I think you're overthinking things but agree with Eric above, that's what I did for the $30 220V air compressor I got at a garage sale... If the machine is grounded and the receptacle is grounded you should be fine

 

[scotts90ranger]

The 14ga wire concerns me. I would think this would be at least 12ga. I wouldn't use 14ga to power anything more than lights on a 15 amp circuit.

220V cuts the amps in half per leg, but yes I would go 12ga

 

[Curious Hound]

The 14ga wire concerns me. I would think this would be at least 12ga. I wouldn't use 14ga to power anything more than lights on a 15 amp circuit.

14gauge wire is rated for 20 amps. BUT, code limits its' use to 15amps in branch circuits, which this is. And the nameplate of the machine says full load is 12amps. So, it's more than fine on a circuit with everything sized by code for 15amps. 15 amps is 15amps whether it's lighting, a lathe, a toaster or recharging a vibrator. The 125% rule accounts for "in-rush current" on inductive loads like motors and transformers.

 

[Curious Hound]

220V cuts the amps in half per leg, but yes I would go 12ga

The 12amps from the nameplate is full load current on both legs. It doesn't get cut in half. The same size motor, 2hp, on 120volts would pull 24amps.

 

[SenorNoob]

15 amps is 15amps whether it's lighting, a lathe, a toaster or recharging a vibrator.

Aren't those usually mains powered at that point?

 

[alwaysFlOoReD]

OT;
All my 5hp motors pull 22-25 amps. Its what I look for in amperage when I look at a "5hp" motor on compressors because of manufacturer inflation.
So why is a 2hp motor pulling the same? Is it less efficient motor?

 

[bobbywalter]

1500 watts is about 12.5 amps at 120 volts on bob math. but bob math is often fawked up by bob.....i bob math a electric hp to 750 ish watts.....


but i trust eric math more than bob math.