Forums | Home Repair | Home Improvement | Painting | Interior Decorating | Remodeling | Landscaping


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 12-14-2009, 09:07 PM   #1
Member
 
Join Date: Mar 2008
Posts: 47
Share |
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


I bought an old, much used craftsman air compressor off of craigslist. It's belt-driven and worked like a charm at point-of-sale.

I am confident with installing electric, not a pro but i have remodeled our entire kitchen, i've done some reading but I am just not 100% sure on this so I want to make sure I understand the setup.

First the specs:
volts 230/115
hertz 60
hp 2.0
rpm 3450
amps 11/22

I was told at pos that the motor can be wired for 120 but it's currently set to 220 - i suppose this makes sense from the specs then. The plug is a standard plug except is has a "wink" to it (like a wink of an eye) - if you are looking straight at it the wink is on the left. I've never seen this before but my impression is that this represents 20amps?

I should note that my intentions are to use it per its current setup as a 220, so my questions below should apply to that.

questions:
do i install a single 20amp circuit? it that sufficient, plus/minus or is 15amp sufficient?
is this suppose to be a double poll or single poll? and how can i tell?
I get the impression that I can pick up any 20A receptacle as long as it has the 'wink' part of the outlet and I am good to go?
12 gauge amp for a 20amp circuit i believe, let me know otherwise.


Thank you all for your time.
capslock is offline   Reply With Quote
Old 12-14-2009, 09:36 PM   #2
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 7,197
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Is it this one.


or this one?

The first one is 240 volt 20 amp. The second one is 120 volt 20 amp.

Use #12/2 cable. If the motor is wired for 240 then use a double pole breaker and connect both black and white to the breaker. No neutral. Install the matching receptacle.
__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is online now   Reply With Quote
Old 12-14-2009, 09:36 PM   #3
Member
 
Join Date: May 2009
Location: Brooklyn, New York (NYC)
Posts: 1,124
Thumbs up

Proper wiring for an electric motor from the breaker box (for an air compressor)


Quote:
Originally Posted by capslock View Post
I bought an old, much used craftsman air compressor off of craigslist. It's belt-driven and worked like a charm at point-of-sale.

I am confident with installing electric, not a pro but i have remodeled our entire kitchen, i've done some reading but I am just not 100% sure on this so I want to make sure I understand the setup.

First the specs:
volts 230/115
hertz 60
hp 2.0
rpm 3450
amps 11/22

I was told at pos that the motor can be wired for 120 but it's currently set to 220 - i suppose this makes sense from the specs then. The plug is a standard plug except is has a "wink" to it (like a wink of an eye) - if you are looking straight at it the wink is on the left. I've never seen this before but my impression is that this represents 20amps?

I should note that my intentions are to use it per its current setup as a 220, so my questions below should apply to that.

questions:
do i install a single 20amp circuit? it that sufficient, plus/minus or is 15amp sufficient?
is this suppose to be a double poll or single poll? and how can i tell?
I get the impression that I can pick up any 20A receptacle as long as it has the 'wink' part of the outlet and I am good to go?
12 gauge amp for a 20amp circuit i believe, let me know otherwise.


Thank you all for your time.
The "Wink" represents 20Amps. But @ 220Volts. A 220Volt circuit in the Good Ol' US of A is, by definition a 2-pole circuit;2 H.P. @ 220v. = 6.78Amps. Taking FLA (Full load Amps) into consideration, 15 Amps. should be sufficient But there is such thing as LRA (Locked Rotor amperes) and for that, 20Amps is better. In any case, if it's set up for 20A. leave it at that. (No matter what) Don't Drink and Drive, Ever!!!
spark plug is offline   Reply With Quote
Old 12-14-2009, 10:09 PM   #4
Member
 
Join Date: Mar 2008
Posts: 47
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Hi, thanks for the input so far,

Its the 5-20 image, which from what joed is saying its a 120v? hmm, now I am conflicted based on the specs I have...


ok well, then there are two questions I have at this point:

-if the specs show 230/115v and 11/22 amps then wouldnt this indicate that it is rigged for 220? How can I be certain here? I do not want to end up with a burned out or blown out motor.

-let's say we determined the compressor is rigged for 220, i understand that there would be two hot lines and no neutral line.

I assume I use 20 -amp breakers, one for each line? does this effectively make 40 amps? Or am i suppose to setup something different? Would a tandem breaker be sufficient?

-now let's assume it's really 110 as joed has indicated, does this mean single-pole with neutral is required?

Last edited by capslock; 12-14-2009 at 10:30 PM. Reason: oops, mistake on amp rating
capslock is offline   Reply With Quote
Old 12-14-2009, 11:19 PM   #5
Idiot Emeritus
 
Join Date: Mar 2008
Location: Fernley, Nevada (near Reno)
Posts: 1,494
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


This is almost certainly a 2 HP motor. If it is connected for 115 volts, it'll draw 22 amps. And trip a 20 amp circuit in about a minute or two. If it is connected for 230 volts, it'll draw 11 amps, and run forever on a 20 amp circuit.

The connection is an internal connection of wires or jumpers inside the motor. It's not all that hard to change it. I recommend you leave it 230.

The plug/receptacle is most likely a NEMA 6-20. Hold the plug like you're going to plug it in to the wall. With the ground prong down, if the sideways prong is on the right, it's a 6-20. If it's on the left, it's a 5-20.

You'll need a two pole 20 amp breaker, some 12/2 wire, a box, and a receptacle. The two pole breaker will give you two hots, and no neutral.

If the motor is connected for 115, and it's plugged in to a 20 amp 240 volt receptacle, it'll most likely trip the breaker before it is damaged. Older motors like this one can take a lot more abuse than newer ones.

You can also check the internal connections to know what voltage it's connected for.

Rob
micromind is online now   Reply With Quote
Old 12-15-2009, 07:46 AM   #6
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 7,197
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Those are the receptacle images. So if you are looking at the plug you will have them reversed.
The only way to be sure of the voltage required is to open the motor wiring connection box and look at the connections. There should be a drawing on the motor or inside the connection cover indicating the wire connection for the two voltages. A quick look should tell you which voltage it is wired for.
__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is online now   Reply With Quote
Old 12-15-2009, 12:25 PM   #7
Member
 
Join Date: Mar 2008
Posts: 47
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


I didn't realize that those were receptical images, in that case it's the 6-20 image.

Ill open the box to make sure, but I am confident on the requirements now. Assuming the motor is set to 220 and i was told that it was, I am to do the following:

-grab some #12 gauge wire
-get 2 20amp breakers (are the small tandem ones ok?)
-wire the white (mark it red or black) into one 20amp breaker
-wire the black into one 20 amp breaker
-feed both wires into a 20amp receptical
-turn on breakers, good to go.

I intend to have a ground wire, but my breaker box is a mix of ground and neutral on the same panel, there is no dedicated ground in the breaker box because of it's age. Is this a problem?

This sound right?
capslock is offline   Reply With Quote
Old 12-15-2009, 01:43 PM   #8
Member
 
joed's Avatar
 
Join Date: Mar 2005
Location: Welland, Ontario
Posts: 7,197
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Get a double pole 20 amp breaker. Two breakers are not acceptable, Tandems or minis are not acceptable either. They won't provide the 240 volts.

Unless you have conduit you must use cable not wires. The cable will have a ground wire in it. Connect it with the other grounds.
__________________
Do not PM with questions that can be asked in a forum. I will not respond.
joed is online now   Reply With Quote
Old 12-15-2009, 02:42 PM   #9
Member
 
Join Date: Mar 2008
Posts: 47
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


joed,

right, it's because i need the 2-pole so that the switch is the same for both...

there is a GE breaker (i have a ge breaker box) which is 2-pole 20amp but it 1inch i.e. same width as a standard single pole breaker. Is this sufficient?

for reference:
http://www.homedepot.com/h_d1/N-5yc1...atalogId=10053

You're right, i meant cable.
capslock is offline   Reply With Quote
Old 12-15-2009, 04:10 PM   #10
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,472
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Quote:
Originally Posted by capslock View Post
joed,

right, it's because i need the 2-pole so that the switch is the same for both...

there is a GE breaker (i have a ge breaker box) which is 2-pole 20amp but it 1inch i.e. same width as a standard single pole breaker. Is this sufficient?

for reference:
http://www.homedepot.com/h_d1/N-5yc1...atalogId=10053

You're right, i meant cable.
NO, that is a tandom breaker.
If you know what you are doing you can make that breaker work, but it easier to get a 2 pole 20 amp that is 2 inches wide.
__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is online now   Reply With Quote
Old 12-16-2009, 01:27 PM   #11
Member
 
Join Date: Mar 2008
Posts: 47
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


hi jbfan,

I'm not trying to be rude here, we just need to discuss this tandem breaker.

From what I have seen at two hardware stores (home depot then an ace hardware) there is the GE breaker I shown you; it's one inch, 2 pole - both switches turn on/off together as they are connected.

From what I understood, a tandem breaker is similar, except that the on/off switches can be worked independently from one another; this is not the case with at least from what i seen, and I am assuming the image i provided is what I seen.

I could not locate in either of those stores a 2inch 20amp 2-pole breaker. I have seen a 1inch 20amp 2-pole break where two on/off switches operate independently from one another and then there is a 1inch 20amp 2-pole breaker where the two on/off switches operate together, meaning you cannot turn one off while leave the other on.

The latter is what I assume I would purchase, and it wouldnt matter at that point that it is only 1 inch.

Is this off-base from the truth?
capslock is offline   Reply With Quote
Old 12-16-2009, 01:38 PM   #12
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,472
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


GE panels will accept slimline breakers.
Slimline breakers also come in 2 pole like the one you show.
This breaker has to be installed so it hits both legs of the panel.
__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is online now   Reply With Quote
Old 12-16-2009, 07:17 PM   #13
Member
 
Join Date: May 2009
Location: Brooklyn, New York (NYC)
Posts: 1,124
Thumbs up

Proper wiring for an electric motor from the breaker box (for an air compressor)


Quote:
Originally Posted by jbfan View Post
GE panels will accept slimline breakers.
Slimline breakers also come in 2 pole like the one you show.
This breaker has to be installed so it hits both legs of the panel.
Actually. this is for Capslock; Let me expand on what Jb fan said. The GE residential, single phase panels can accept both, the slimline (thin) and full size breaker. With the full size, Two pole breaker it's quite simple. You just "Plug" it in and you "Hit" (Make contact with) both legs of the circuit. With the Thin breaker, on the other hand, you may get power in both breakers but only 120v. The trick is, to insert it where one pole ends and the other begins.
(No matter what) Don't Drink and Drive, Ever!!!
spark plug is offline   Reply With Quote
Old 12-21-2009, 07:47 AM   #14
Member
 
Join Date: Mar 2008
Posts: 47
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


jbfan and sparkplug,

so taking your input I went doesn to the box to take a look at it again, with all of the breakers in there I couldnt see 100%, though i started to get your idea.

When i went to home depot i seen the same sub panel model being sold and open so i looked at it and now I understand fully what you both are referring to.

The slimline 2-pole will have to sit in "the middle" between the two locations where full 1inch breakers would go. This will allow one side of the slimline 2-pole to be touching the plate leading from the one hot lead and the other side of the breaker will touch the plate leading from the other hot lead.

In this fashion I would still have available two me two small slots for single slimline breakers for expansion or current use (i would have one slot not in use but the other would be used with a slimline 15amp for my dining room).


Quote:
Get a double pole 20 amp breaker. Two breakers are not acceptable, Tandems or minis are not acceptable either. They won't provide the 240 volts.
I am assuming here you are talking about the single-pole minis and not the double-poll which i have decided to use?
capslock is offline   Reply With Quote
Old 12-21-2009, 09:12 AM   #15
Electrical Contractor
 
jbfan's Avatar
 
Join Date: Jun 2004
Location: Newnan GA
Posts: 5,472
Default

Proper wiring for an electric motor from the breaker box (for an air compressor)


Yes. A 2 pole mini with a common trip is what you are after.
I'm glad you made sense of what I was talking about.
Good Luck
__________________
Yes I am a Pirate, 200 years too late. "Jimmy Buffett"
jbfan is online now   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
New Compressor - Wrong Charge? shayneb HVAC 4 08-23-2008 08:13 AM
electric wiring for fluorescent lamp toronbolo Electrical 3 03-24-2008 12:16 PM
Heat Pump compressor trips circuit breaker joejean HVAC 3 08-28-2006 12:15 PM
Electric Range Wiring manhattan42 Electrical 11 07-05-2006 05:03 PM
Wiring from electric motor Submarineman Electrical 1 06-17-2005 12:50 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.