220v for compressor wiring

Reply

  #1  
Old 03-03-10, 11:11 AM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
220v for compressor wiring

Hey guys,

When we had our house built I asked the electrician to add 220V into my garage for a future compressor. Well I picked up a used compressor yesterday and went to plug it in... but the plugs are different. I'm attaching a picture of the wall plug, the compressor motor (which says 240V) and the plug that's on the compressor. Is it ok to just change the plug on the end of the compressor to one that matches the wall plate?


Thanks!




 

Last edited by the_dude; 03-03-10 at 01:11 PM.
  #2  
Old 03-03-10, 11:52 AM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,581
Received 13 Votes on 11 Posts
If the electrician was smart he would have asked you the amp rating of the compressor. With out knowing that whatever he did was pure guess. Tell us the breaker size, wire size to receptacle, and amp draw of the compressor and we can help you.
 
  #3  
Old 03-03-10, 12:17 PM
I
Forum Topic Moderator
Join Date: Feb 2005
Location: Near Lansing, Michigan
Posts: 10,942
Received 44 Votes on 42 Posts
Originally Posted by the_dude View Post
I'm attaching a picture
Your pictures aren't loading from 96.52.45.34 -- is the IP and URL correct? You can upload to imageshack, photobucket, etc if your hosting isn't up.

Is it ok to just change the plug on the end of the compressor to one that matches the wall plate?
Usually not, but we can know for sure once the pics are up.
 
  #4  
Old 03-03-10, 01:05 PM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
thanks for the replies. I'm trying to figure out why the pics aren't working and I'll move them. The Motor itself says it's 1phase, 14amps, max 3450 rpm. Motor Model # MO-3024 built by A.O.Smith on a devilbiss compressor. The breaker is two 15amp breakers, and the wiring is NMD90 14AWG.

Thx

edit: ok pics should be working.
 
  #5  
Old 03-03-10, 01:32 PM
I
Forum Topic Moderator
Join Date: Feb 2005
Location: Near Lansing, Michigan
Posts: 10,942
Received 44 Votes on 42 Posts
It would be very borderline to run the compressor on your existing 15A circuit given that the motor rating is 14A. The compressor currently has a 20A (6-20P) plug on it, but it was clearly added aftermarket so no telling if it's the right one from the mfg. You could replace the plug on the compressor with a 6-15 and see if it will start without tripping the breaker.

Honestly I would only want to run this compressor on a 20A circuit.
 
  #6  
Old 03-03-10, 01:33 PM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
ok thanks. So can the breakers be switched out to 20A breakers?
 
  #7  
Old 03-03-10, 01:42 PM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 15,238
Received 108 Votes on 94 Posts
The breaker size can only be changed if the wiring is #12. To do otherwise would create a fire hazard.
 
  #8  
Old 03-03-10, 02:51 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,581
Received 13 Votes on 11 Posts
Id talk to the electrician if he installed this without knowing the amperage for your compressor he made a mistake in my opinion. He should have asked. He needs to correct his mistake hopefully at reduced cost.
 
  #9  
Old 03-03-10, 03:11 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,915
Received 283 Votes on 247 Posts
Originally Posted by ray2047 View Post
Id talk to the electrician if he installed this without knowing the amperage for your compressor he made a mistake in my opinion. He should have asked. He needs to correct his mistake hopefully at reduced cost.
Or the homeowner should have told him what he was intending to buy. Good communication goes both ways.

I do agree that if the electrician did not know what kind of compressor the HO was going to buy, he would have at least installed a 20 amp circuit. At least that is what I would have done.
 
  #10  
Old 03-03-10, 03:13 PM
I
Forum Topic Moderator
Join Date: Feb 2005
Location: Near Lansing, Michigan
Posts: 10,942
Received 44 Votes on 42 Posts
Originally Posted by the_dude View Post
ok thanks. So can the breakers be switched out to 20A breakers?
Not without rewiring the circuit with larger wire.
 
  #11  
Old 03-03-10, 07:31 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: United States
Posts: 10,782
Received 99 Votes on 89 Posts
The 15 amp breaker may not trip initially with no air pressure in the tank, but when you start using air and the compressor starts to cycle under load, I think the 15 will trip.
 
  #12  
Old 03-03-10, 08:08 PM
ray2047's Avatar
Member
Join Date: Mar 2006
Location: USA
Posts: 33,581
Received 13 Votes on 11 Posts
Pros, if the compressor was hard wired could the OP use #14 on a 20a circuit or am I remembering the code wrong? Or is the FL to close to use on #14.
 
  #13  
Old 03-03-10, 08:31 PM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
Thanks for all the replies. I suppose I'm going to have to pull a new wire. I may as well pull a 10Ga so I can put a 30Amp breaker on it. From what I am reading a 14A motor can draw up to 30A on initial startup
 
  #14  
Old 03-03-10, 08:46 PM
CasualJoe's Avatar
Member
Join Date: Jan 2010
Location: United States
Posts: 10,782
Received 99 Votes on 89 Posts
There is NO need for #10 wire. I'd run a new circuit with #12 wire and try a 20 amp breaker, I think it will be fine. If the 20 trips, change it to a 25 amp breaker (you might have to order a 25 amp brkr).
 
  #15  
Old 03-03-10, 10:18 PM
braether3's Avatar
Member
Join Date: Nov 2009
Location: wisconsin
Posts: 413
Received 0 Votes on 0 Posts
I have a air compressor that claims its 16 amp at 120v and it has a 14awg cord on and a nema 5-15 and Iv never had it trip a breaker on its own.

first try the 6-15 plug and see how it starts

However if this is a unit you will be using day in and day out then yes you better run 12 gauge wire but if its just to drive a few nails or pump up the kids bike tire...then you could probably live on that 15 amps
 
  #16  
Old 03-04-10, 06:17 AM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
I'll be using sprayguns and board sanders primarily, so unfortunately I think I'll have to upgrade. But it's good to know that 12G will be enough!
 
  #17  
Old 03-04-10, 06:35 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,915
Received 283 Votes on 247 Posts
Originally Posted by ray2047 View Post
Pros, if the compressor was hard wired could the OP use #14 on a 20a circuit or am I remembering the code wrong? Or is the FL to close to use on #14.
That is a really good thought but I did some research and the minimum size wire for this motor is #12.
 
  #18  
Old 03-04-10, 07:43 AM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
Originally Posted by CasualJoe View Post
There is NO need for #10 wire. I'd run a new circuit with #12 wire and try a 20 amp breaker, I think it will be fine. If the 20 trips, change it to a 25 amp breaker (you might have to order a 25 amp brkr).
So I can run a 25amp breaker (double) on 12/3?

thx
 
  #19  
Old 03-04-10, 07:57 AM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 13,915
Received 283 Votes on 247 Posts
Originally Posted by the_dude View Post
So I can run a 25amp breaker (double) on 12/3?

thx
For a motor load, yes, you can use a 25 amp. You shouldn't need 12/3 though, just 12/2 with a ground. No neutral is needed for your compressor.
 
  #20  
Old 03-04-10, 08:07 AM
T
Member
Thread Starter
Join Date: Sep 2004
Location: Canada
Posts: 158
Received 0 Votes on 0 Posts
Thank You. I appreciate all the advice.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: