220 Compressor-Hard Wired or a Plug?

[tomshep]

I was curious as to how many hard wire their compressor compared to those that use a plug so they can have the option of running a welder (or other item) in that area of their shop.

I am considering the plug situation. I will have 220 in a few other walls in the shop but the flexibility of plugging in a welder on that wall is appealing without needing to use 2x the wire, breaker, etc. for another plug.

Thanks, Tom

 

[sr71]

plug.....

 

[HAP]

Plug for sure. Just get one of the big 50 amp ones even if you dont need that rating.

 

[Doxhog]

Go with the plug. I did it with the on demand water heater for my wash up sink and my air compressor. Use the same outlet for each, just unplug the one I was using and plug in the one I need. Can't wash my hands and use my air compressor at the same time.

 

[rvr6000]

Yep....used a plug as well.

 

[GeorgiaHybrid]

Hard wired but mine is in a dedicated room with a circuit that was run for it.

 

[mdbeck1]

Plug. It will make it easier to replace the compressor later. Plus if I NEED a 220VAC plug I've got one...

 

[larry4406]

Plug. Not only can you use the outlet for something else if necessary, the plug acts as your local service disconnect. I used a 50A range cord with integral pigtail.

 

[Falcon67]

Hard wire, dedicated circuit. It's going in a closet, not somewhere you'd plug in a welder. And 240V on 12-3 wire is not typically a 240V welder circuit.

 

[olytdi]

Plug is fine if you make sure that your recepticle and the wire run/breaker used is compatable with your welding needs as that will likely exceed the needs of your compressor. As such, you may be wiring in overkill mode for your compressor.

 

[the_glassman]

Am I correct in assuming that hardwired requires a safety disconnect switch per NEC? And a pig tailed plug and socket setup up does not?

 

[malibu101]

Am I correct in assuming that hardwired requires a safety disconnect switch per NEC? And a pig tailed plug and socket setup up does not?

You are very close to correct. The breaker can be used as the safety disconnect as long as it's within sight and less than 50' away. Otherwise a disconnect must be used that is within sight and less than 50'.
Yes, a cord and plug connection is acceptable as a safety disconnect.

 

[padroo]

If it's on wheels I would go with the plug and if it is one of those upright compressors with four mounting feet I would hard wire it.
Manufacturers owners manual should tell you the best way.

 

[Charles (in GA)]

Be aware that many devices (pressure switches, receptacles, etc) are not designed or rated for "cord" wire, that is, the very flexible, fine stranded wire used in cords. They may only be rated for use with "wire", either solid or stranded.

Charles

 

[dagoat_1]

Why not Hardwire with a recepticle running from there? Here is what I did with my my devibiss. This way I can have both welder and compressor at the same cornerof the garage.

(from panel)----------(Shutoff Switch)----------(recepticle)
I
I
I
I
(Hardwire to Compressor)

 

[dagoat_1]

Damn my diagram didnt come out the way I typed it but you should get the idea. The hardwire to compressor down runs from the shutoff switch.

 

[pro machine Engineering]

Im hard wired on the compressor into a fusable knife switch. I dropped down from the knife switch and added a plug for a welder. I used a heavy gauge wire and had an electrician verify what I was doing would be safe and right.

 

[Spam16v]

I put a plug on mine. 6-7a specified draw on the tag, ran 14/2 on a 15a breaker w/a 220 asian looking socket.

 

[PsRumors]

My compressor is behind the shop. I ran a 100 amp 6 breaker sub panel right next to it then hardwired the compressor. This gives me the option to add plugs as needed.

 

[evintho]

I went a little different route 'cause I bought my compressor before I got my welder. I hard wired the compressor and after I got my Hobart 210, I spliced in a 220v receptacle to the compressor hard wiring. Just have to remember to shut off the compressor before using the welder! So far, so good!

 

[Steves32]

Compressor is hard wired w/ a fused disconnect & whip.
I have other dedicated outlets for welder & lift.

 

[Chetter]

I am in the process of installing my compressor and I am making my own plug using a 50amp 250v plug that you assemble into the configuration you need for the receptacle that I am using which is also a 50amp 250v plug. I am using the same #6 wire that I am using for wiring the receptacle into the breaker box with a 30amp double throw breaker. I checked with an electrcian to be sure that what I am doing is safe and compliant and he said it is, so I can unplug it to use the mig welder that is also 220v and the plug will go into the receptacle I am using. I have no need to use both at the same time so I decided to go the plug route. I will have it double checked by an electrician before turning it on just to be sure. The compressor I got is the Husky Pro 60 gal 3.2 HP that requires 220v to operate.

 

[PRH44]

Please be adivised if you plan to disconnect or reconnect under load expect an arc. Motor stratup current is 6 times running load. If you plan to do this often the receptacle and you male plug will deteriorate over time. A disconnect switch is more safe and will last longer.

 

[Chetter]

Please be adivised if you plan to disconnect or reconnect under load expect an arc. Motor stratup current is 6 times running load. If you plan to do this often the receptacle and you male plug will deteriorate over time. A disconnect switch is more safe and will last longer.

Point well taken and thanks for that advice. I will throw the breaker off to connect and disconnect.

 

[036.6turbo]

Hard wired but mine is in a dedicated room with a circuit that was run for it.

Plus plugs for welders.

 

[Chetter]

Finished my compressor install today. I put in the 30amp double poll breaker used #6 wire from breaker to the wall plug I installed which was a lot of fun trying to pull the wire through the 3/4" pvc flex conduit rated for wet locations but it was what I wanted to use. Checked to make sure I had the 240v both at the breaker and the new plug. Wired the compressor with 3 wire cord that I believe is #8 or 10 wire and hooked the power cord up to the plug that I am using. I started the compressor and let it run for 30mins under no load to break in the pump per the instructions of Husky/ Campbell/Hausfield. For the time being I just reused my hand crank hose reel after getting the little bit of plumbing needed to hook it up. I will run hard line later after I figure out where I want to run my drops. I am going tomorrow to get another ball valve in 3/8" and with a little work and more plumbing pieces, try and have a drain setup that I can use easily for draining the tank instead of reaching under the tank to open the drain that comes with on the tank. I will post a pic tomorrow of the completed project.

 

[pattenp]

Finished my compressor install today. I put in the 30amp double poll breaker used #6 wire from breaker to the wall plug I installed which was a lot of fun trying to pull the wire through the 3/4" pvc flex ........

If you only needed 30A why did you use #6 when #10 would have worked?

 

[Chetter]

If you only needed 30A why did you use #6 when #10 would have worked?

It was wire that I had instead of buying new and my electrcian friend said it would be fine and if I ever needed to use a 50 amp breaker in the future I am all set.

 

[pattenp]

It was wire that I had instead of buying new and my electrcian friend said it would be fine and if I ever needed to use a 50 amp breaker in the future I am all set.

 

[PT Doc]

240v Hobart was quoted to need 50a 6 wire so I did the same as you did. Didnt want to run more wire since it already cost about $200. You are set for future needs.

 

[Los59]

A little late in the conversation guys but I am unsure on a couple things.
The previous owner of my home had installed quite a bit of extra electrical in the garage to run heavier equipment. I just purchased a Kobalt 80 Gal. compressor that requires these specs for electrical

Voltage 230
Amps 22.0

My concern or question is can I use a dryer power cord to run this monster? the plugs and breakers that the previous owner had installed are detailed in the photos below

I bought a dryer cord which matches the plugs which specs are

10/4 Gauge
4-wire
30 Amp-125/250V 6ft Cord

Now, can will this work properly? I heard elsewhere not to use a dryer cord it was after the purchase of the cord. Have any of you done this? Everything seems to be up to specs but still insure, I dont want to hook it up and mess something up.

Thanks in advance guys!

 

[pattenp]

Los59, the 30A circuit is okay for the compressor. The outlet is a 3/w ground which provides both 125V and 250V and your compressor only needs 250V which is 2/w ground. You can use that outlet but it's really not the correct one to use. Your compressor wire won't use the L shaped prong which is a neutral.

 

[Los59]

So it should be fine to connect it with this cord to this outlet even though the L shaped prong won't be used? I'm sure I will have to cap the neutral wire. Would it be wise to install a new outlet to a proper one? Or would you guys just stay with this configuration to run the equipment? Excuse all the questions just trying to protect my investment and my knowledge of electrical is extremely novice.

 

[Norcal]

If the equipment is not portable then a cord should not be used, flexible cord is not to be used in place of permanent wiring. Hard wire it & use a disco.

 

[Los59]

Disco? I always thought it would be preferance as whether to use plug or hard wire like the thread is titled? I don't want to seem like I don't want to take your recommendation into consideration but I already have the electrical wired in the garage for such use. Just want to know if why I am planning to use is up to par.

 

[Norcal]

Disco? I always thought it would be preferance as whether to use plug or hard wire like the thread is titled? I don't want to seem like I don't want to take your recommendation into consideration but I already have the electrical wired in the garage for such use. Just want to know if why I am planning to use is up to par.

Disco = Disconnect. Cord & plug connecting non portable equipment is not code compliant, flexible cords are not permitted to replace permanent wiring. See NEC art. 400.8(1).

 

[pattenp]

I have a different take on it. I believe flex cord is okay on the compressor because 400.8(1) says not permitted as a substitute for the fixed wiring of a structure.
I think 400.7(7) permits it.

Edit: Guess I should have put what 400.7(7) says....

Uses Permitted. (7) Prevention of the transmission of noise or vibration.
I'd think a compressor qualifies for that reason of permitted use.

Disco = Disconnect. Cord & plug connecting non portable equipment is not code compliant, flexible cords are not permitted to replace permanent wiring. See NEC art. 400.8(1).

 

[Los59]

Lol... Conflicted. Yay or Nay on my expected connection?

 

[Aceman]

You have to watch the HP ratings. A 50 amp Leviton recep only has a 3 HP rating. So for most members on here with larger compressors this isn't even an option.

Specs taken from here:
http://www.leviton.com/OA_HTML/ProductDetail.jsp?partnumber=5374&section=42418&minisite=10251

 

[fordcragar]

I used a plug for mine. My welder has a separate plug.