Adding compressor to 220v in my garage

[buickanddeere]

If the motor was 100% efficient and had a PF of 1. It would make 4.83HP with 15 amp and 240V. Probably running at approx 70% so 9.3amp would be doing work , 4 amps wasted as heat and 1.7 more amps of reactive power.

 

[hr3]

That makes sense to me, but I seem to recall numerous discussions about this not being acceptable in the NEC. Also in many discussions about proper grounding of generators. Can anyone elaborate?

Your right ground rod does not equal a forth wire for grounding..

 

[hr3]

There is an easy fix for your situation ..

1st. Install the proper outlet for your welder..
2nd. Put a new cord end on your welder..
3rd. Put a second cord end on a 2 circuit breaker box..
4th. From the load side of the new breaker box wire to your compressor..

You can mount the new breaker box next to the welder outlet and just plug it in when you want.. Simple fix...

 

[Scotty Dive]

This is what I intend on doing:

1. Pull the 220 out of the outlet it resides in now and terminate it into a sub panel box. Assuming I can do that with a three wire set up
2. Install a 50 amp and a 30 amp double throw breakers
3. Wire a new line from the 50 amp to the existing outlet - change outlet to proper 220v outlet
4. Replace welder plug to a matching 220 plug that mates with the new 220 outlet
5. Wire 10 ga from 30 amp breaker to new to me compressor.

Sound good?

 

[Gator6x4]

This is what I intend on doing:

1. Pull the 220 out of the outlet it resides in now and terminate it into a sub panel box. Assuming I can do that with a three wire set up
2. Install a 50 amp and a 30 amp double throw breakers
3. Wire a new line from the 50 amp to the existing outlet - change outlet to proper 220v outlet
4. Replace welder plug to a matching 220 plug that mates with the new 220 outlet
5. Wire 12 ga from 30 amp breaker to new to me compressor.

Sound good?

The plugin you are currently using is for a 110 volt AIr Conditioner. The plug and the pig tail on the AC unit are designed like that to prevent someone from plugging into a regular outlet. I am surprised you haven't enjoyed some hot times using it to power a 220 volt unit.

You need four (4) wires going to a 220 plug in. Most 220 wires with four wires have a red, black, green and white wires. the red and black each carry 110 volts, the green is for ground and the white is the neutral safety ground. 220 volt appliances require a minimum of number 10 wire. Most compressors require number eight (8) wire. Some require number (6).

 

[bigdeano]

This is what I intend on doing:

5. Wire 12 ga from 30 amp breaker to new to me compressor.

Sound good?

You can't do this if the wire is part of the building. The breaker is there to protect the wire from overheating. With a 30 amp breaker you will need 10 ga wire. Someone may plug a 30 amp load in and overheat the 12 ga wire, causing a fire.

 

[LD1]

You need four (4) wires going to a 220 plug in.

I'm not an electrician so forgive my ignorance, but I have been told that 4-wire is only needed IF the appliance has 220v AND 110v circuits within it. Like a stove that has 220 heating elements and a 110v digital display.

But things such as a compressor or welder that are 220 ONLY, 3-wire is okay??

 

[hr3]

This is what I intend on doing:

1. Pull the 220 out of the outlet it resides in now and terminate it into a sub panel box. Assuming I can do that with a three wire set up
2. Install a 50 amp and a 30 amp double throw breakers
3. Wire a new line from the 50 amp to the existing outlet - change outlet to proper 220v outlet
4. Replace welder plug to a matching 220 plug that mates with the new 220 outlet
5. Wire 10 ga from 30 amp breaker to new to me compressor.

Sound good?

#1 No.. A remote panel needs 4 wires,,,
#2 Yes
#3 Yes
#4 No.. 30amp. breaker = #10 wire "at least"

 

[Scotty Dive]

You can't do this if the wire is part of the building. The breaker is there to protect the wire from overheating. With a 30 amp breaker you will need 10 ga wire. Someone may plug a 30 amp load in and overheat the 12 ga wire, causing a fire.

My bad - meant to say 10 gauge. I fixed my post to reflect that.

All I have out there is three wires - black, white and un sheathed twisted aluminum. The welder only has three wires as well. I called the compressor (Campbell Hausfeld) manufacturer and they want 10 gauge run behind a 30 amp double throw breaker.

 

[bigdeano]

220 volt only loads like water heaters are wired with 2 conductor plus ground cable. You should be fine. I'm not an electrician, but I wired a couple of new houses and studied the code. I stayed at a motel once too