To avoid these ads, REGISTER NOW!

Air Compressor wiring help

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
I have a Quincy QT 54 I want to wire up, but the breaker is full. I recently moved into this house and didn't realize until after the purchase it has a 100a panel and it is full. The panel wont accept tandem breakers to free up a spot. I can free up a spot with the 20a square d breakers that will take 2 wires. I can wire the air compressor to the oven breaker since my oven is gas and tape off the wire. My concern is the service wire comes in the bottom of the breaker and I don't want to get shocked. I would appreciate any help what the best course would be.

Thank You
 

Attachments

  • pic1.jpg
    pic1.jpg
    699.6 KB · Views: 86
To avoid these ads, REGISTER NOW!

blwn31

Active member
Joined
Aug 16, 2014
Messages
31
Dumb question but, why can't you put tandems in there. Are they not available? As far as getting shocked, trip the main breaker and work that way. If you can't trip a main, trip the breakers you are going to remove before you remove any wires. And don't touch the bus bar when you replace the breakers.

Keith
 
OP
C

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
Im talking about the lines coming from the meter can, I have tried simmens and square d tandems and they don't fit.
 

rocco611

Member
Joined
Sep 11, 2022
Messages
12
If there is no service disconnect between the panel in the picture and your meter, you would have to be careful, but it can be done reasonably safely by shutting off the main breaker in the panel . I am not seeing the main in your panel though as it would be above the frame in the picture. if your not comfortable doing it yourself do as much of the wiring between your compressor and the service panel then have an electrician finish it. If you let your utility know you want to upgrade the panel, you can usually contact them ask them to disconnect and reconnect your service, sometimes without a fee. They really hate when someone shorts out a circuit pops a primary fuse or blows up one of their transformers.
 
OP
C

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
If there is no service disconnect between the panel in the picture and your meter, you would have to be careful, but it can be done reasonably safely by shutting off the main breaker in the panel . I am not seeing the main in your panel though as it would be above the frame in the picture. if your not comfortable doing it yourself do as much of the wiring between your compressor and the service panel then have an electrician finish it. If you let your utility know you want to upgrade the panel, you can usually contact them ask them to disconnect and reconnect your service, sometimes without a fee. They really hate when someone shorts out a circuit pops a primary fuse or blows up one of their transformers.
Thank You I will probably run the romex and the air compressor 10/3 cord to junction box and have a election swap out breaker for the stove since I have a gas stove. My last house the feeder wires came in from the top so it wasn't an issue.
 

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
Thank You I will probably run the romex and the air compressor 10/3 cord to junction box and have a election swap out breaker for the stove since I have a gas stove. My last house the feeder wires came in from the top so it wasn't an issue.
That's a negative on the 10/3 cord, and any other kind of cord. You want 8/2 romex and just use the existing range breaker. It should be a 40 or 50 and you can use up to a 60 for a five horse compressor with #10 wire.

It's a Homeline panel and if it's listed for tandem breakers, they would only fit on the bottom. Probably only the bottom two spaces on each side. Looking at the picture, it doesn't appear that the bottom right space doesn't have the notch, so it's a no go on the twins.

What's the concern about getting shocked by the service wire? The only places you are going to get bit is where the bus bar is exposed (lower right corner) and stripped sections of wire. Just loosen the screws on the range breaker, take the wires off, tape or wire nut the ends, strip 1/2" off the black and white of the romex, put a band of black tape around the white wire to mark it as a hot and put them under the screws and tighten them up. Also don't forget to land the ground wire. Done. If you want to shut the main off, go ahead, but I've seen several mains that were shut off and wouldn't turn back on.
 
Last edited:
OP
C

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
That's a negative on the 10/3 cord, and any other kind of cord. You want 10/2 romex and just use the existing range breaker. It should be a 40 or 50 and you can use up to a 60 for a five horse compressor with #10 wire.

It's a Homeline panel and if it's listed for tandem breakers, and it probably isn't, they would fit on the bottom two spaces on each side. Otherwise, it's going to be a no go.

What's the concern about getting shocked by the service wire? The only places you are going to get bit is where the bus bar is exposed (lower right corner) and stripped sections of wire. Just loosen the screws on the range breaker, take the wires off, tape or wire nut the ends, strip 1/2" off the black and white of the romex, put a band of black tape around the white wire to mark it as a hot and put them under the screws and tighten them up. Also don't forget to land the ground wire. Done. If you want to shut the main off, go ahead, but I've seen several mains that were shut off and wouldn't turn back on.
My concern is the feeder wire coming in on the bottom left of the panel runs right up against the range breaker that is circled. Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit and a 30a double pole breaker without any issues.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,994
Location
Modesto, CA
I have a Quincy QT 54 I want to wire up, but the breaker is full. I recently moved into this house and didn't realize until after the purchase it has a 100a panel and it is full. The panel wont accept tandem breakers to free up a spot. I can free up a spot with the 20a square d breakers that will take 2 wires. I can wire the air compressor to the oven breaker since my oven is gas and tape off the wire. My concern is the service wire comes in the bottom of the breaker and I don't want to get shocked. I would appreciate any help what the best course would be.

Thank You

What is the HP rating on the motor? 5HP? if so you will need #10 THWN or #8 NM-b. breaker can be max 70a.

what is the rating on the oven breaker?

you wont get shocked by the service entrance because it is insulated wire

Im talking about the lines coming from the meter can, I have tried siemens and square d tandems and they don't fit.
looks like you have a SQ D panel. tandems may only fit in certain places. what does the breaker panel label say as to where tandems can be installed?
 

Norcal

Well-known member
Joined
Mar 16, 2008
Messages
13,752
My concern is the feeder wire coming in on the bottom left of the panel runs right up against the range breaker that is circled. Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit and a 30a double pole breaker without any issues.
Without any issues?? I don't think not complying with code is not a issue, cords are not a substitute for permanent wiring.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,994
Location
Modesto, CA
If there is no service disconnect between the panel in the picture and your meter, you would have to be careful, but it can be done reasonably safely by shutting off the main breaker in the panel . I am not seeing the main in your panel though as it would be above the frame in the picture. if your not comfortable doing it yourself do as much of the wiring between your compressor and the service panel then have an electrician finish it. If you let your utility know you want to upgrade the panel, you can usually contact them ask them to disconnect and reconnect your service, sometimes without a fee. They really hate when someone shorts out a circuit pops a primary fuse or blows up one of their transformers.
shutting off the main breaker in the panel wont shut the power off to the service entrance wire so no point in that.
 

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
My concern is the feeder wire coming in on the bottom left of the panel runs right up against the range breaker that is circled. Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit and a 30a double pole breaker without any issues.
That feeder wire isn't going to hurt you. There is insulation on it or it would be shorted out.

I messed up, If you're going to use romex, it has to be an 8/2. You can't use SOOW because, well because you can't. I'm not going to screw around opening up the code book to cite an article you aren't going to read anyway. You might not have had any issues before and probably wouldn't now, but that doesn't make it right.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,994
Location
Modesto, CA
Thank You I will probably run the romex and the air compressor 10/3 cord to junction box and have a election swap out breaker for the stove since I have a gas stove. My last house the feeder wires came in from the top so it wasn't an issue.
NM-b needs to be #8/2 if motor is 5HP.... 10/3 cordage would not be kosher here.... use MC or FMC with #10
That's a negative on the 10/3 cord, and any other kind of cord. You want 10/2 romex and just use the existing range breaker. It should be a 40 or 50 and you can use up to a 60 for a five horse compressor with #10 wire.
10/2 NM-b is too small for 5HP
My concern is the feeder wire coming in on the bottom left of the panel runs right up against the range breaker that is circled.

you still havent told us what your concern is. there is no issue with insulated service entrance wire touching other wires or breakers.... not sure what the issue is here.... if it causes you concern just move it out of the way
Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit and a 30a double pole breaker without any issues.
cordage is not a replacement for building wire..... putting cordage in FMC is even worse.... definitely not to code
 
OP
C

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
That feeder wire isn't going to hurt you. There is insulation on it or it would be shorted out.

I messed up, If you're going to use romex, it has to be an 8/2. You can't use SOOW because, well because you can't. I'm not going to screw around opening up the code book to cite an article you aren't going to read anyway. You might not have had any issues before and probably wouldn't now, but that doesn't make it right.
Thanks, I was under the impression you could run a cord from the air compressor to a junction box and wire nut the romex from the breaker.
 
OP
C

cquint

Member
Joined
Jan 18, 2021
Messages
12
Location
Tennessee
NM-b needs to be #8/2 if motor is 5HP.... 10/3 cordage would not be kosher here.... use MC or FMC with #10

10/2 NM-b is too small for 5HP


you still havent told us what your concern is. there is no issue with insulated service entrance wire touching other wires or breakers.... not sure what the issue is here.... if it causes you concern just move it out of the way

cordage is not a replacement for building wire..... putting cordage in FMC is even worse.... definitely not to code
I guess my fear wasn't warranted, I didn't realize you couldn't be shocked from the insulated wire in the breaker.
 
To avoid these ads, REGISTER NOW!

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
Thanks, I was under the impression you could run a cord from the air compressor to a junction box and wire nut the romex from the breaker.
You can run a cord from the compressor starter but not the breaker. The only place you stated anything about a cord was in the first post, which led me to believe you were running the cord inside the wall from the breaker to the box.
 

rocco611

Member
Joined
Sep 11, 2022
Messages
12
10/3 usually means three conductors with a ground, you only need 2 conductors with ground. look up the current draw of the compressor then use the appropriate wire size for the max current draw. if you are surface mounting the box and using conduit or armored flex then use thhn wire inside the conduit not romex. romex inside a wall is fine , but not for conduit. the breaker in the service panel is to protect the wiring not the compressor, the breaker needs to be sized to the wire being used. the compressor should have its own protection for the motor.
 

walta

Well-known member
Joined
Jan 13, 2017
Messages
2,309
Location
Dutzow Missouri
If the blue arrow points to the wires feeding this panel from the meter, then the yellow arrow points to the main breaker for this panel. With the main breaker off the panel is safe with the exception of the screws of the main breaker.

If it were me, I would turn off the main and the range breakers. Then disconnect tape up and labels unused wires going the range. Use the now empty breaker to power your compressor.

Just be aware the real danger is not so much getting shocked the real danger is that you might drop a tool and if it should find a way to connect one or both buss bars to each other or panel case. If that happens the tool could be vaporized into conductive plasma ball IE great balls fire.

If you are unsure about doing this work the smart move is to pay hundred or two it will cost for a pro.



Walta
 

Attachments

  • pic11 copy.jpg
    pic11 copy.jpg
    710.5 KB · Views: 58

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
10/3 usually means three conductors with a ground, you only need 2 conductors with ground. look up the current draw of the compressor then use the appropriate wire size for the max current draw. if you are surface mounting the box and using conduit or armored flex then use thhn wire inside the conduit not romex. romex inside a wall is fine , but not for conduit. the breaker in the service panel is to protect the wiring not the compressor, the breaker needs to be sized to the wire being used. the compressor should have its own protection for the motor.
10/3 cord is three conductors. Black, white, and green. In one of the posts he stated SOOW, so cord is what he meant.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,994
Location
Modesto, CA
10/3 usually means three conductors with a ground, you only need 2 conductors with ground. look up the current draw of the compressor then use the appropriate wire size for the max current draw. if you are surface mounting the box and using conduit or armored flex then use thhn wire inside the conduit not romex. romex inside a wall is fine , but not for conduit. the breaker in the service panel is to protect the wiring not the compressor, the breaker needs to be sized to the wire being used. the compressor should have its own protection for the motor.
this is not the correct way to size wire for a motor circuit under the NEC. it is to be sized by the table FLC amps NOT the nameplate amps

there is no code prohibition for NM-b (Romex) inside conduit indoors.
 

rocco611

Member
Joined
Sep 11, 2022
Messages
12
yes 10/3 cord is different than 10/3 romex. I was trying to clarify the OP's comment (Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit.) for someone that is not an electrician its important understand what the electrical terms mean and how they are affected by the electrical code. I am assuming he is going to break into the sheetrock, punch out a plug in the service panel , possibly run romex into the box, then run conduit with individual wires (thhn) over to the location of the compressor. then either connect the compressor to a box at that end with flex or install the appropriate plug and short cord to the compressor. If I were planning on running a 220v welder, saw etc. I would opt for a plug. then he could unplug the compressor and plug something else in.
 
Last edited:

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
yes 10/3 cord is different than 10/3 romex. I was trying to clarify the OP's comment (Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit.) for someone that is not an electrician its important understand what the electrical terms mean and how they are affected by the electrical code. I am assuming he is going to break into the sheetrock, punch out a plug in the service panel , possibly run romex into the box, then run conduit with individual wires (thhn) over to the location of the compressor. then either connect the compressor to a box at that end with flex or install the appropriate plug and short cord to the compressor. If I were planning on running a 220v welder, saw etc. I would opt for a plug. then he could unplug the compressor and plug something else in.
Plugging in a 5 horsepower compressor is against code unless the cord and plug are rated for 5 HP, and trust me when I tell you this, it's out of the budget. It's also against the code to run cord inside a wall or any type of conduit. NEC 400.12 will tell you when and where you can't use cord. You can Google it.
 
Last edited:

rocco611

Member
Joined
Sep 11, 2022
Messages
12
cquint, (op) to avoid overcomplicating your installation, does the manual for the compressor give specs for wiring the compressor? I couldn't find a manual for it online, I looked at a picture of the model of the compressor you are going to connect. It appears that all the current goes through the pressure switch and not a contactor like all other 5hp and larger compressors I have seen. most 5hp and larger motors I have seen as well as some smaller ones that draw a large amount of current use a contactor that is separate from the the pressure switch and also contain overload protection with a timer. I wonder about the actual rating of this motor and its current requirements.
 

PoorUB

Well-known member
Joined
Mar 29, 2021
Messages
11,622
Location
Fargo, ND
My concern is the feeder wire coming in on the bottom left of the panel runs right up against the range breaker that is circled. Im not a electrician, so I don't understand the issue with using 10/3 soow. My last house I ran 10/3 wire through metal flex conduit and a 30a double pole breaker without any issues.
If you are running conduit, why run romex or any other type of cable. Buy individual THHN of the appropriate size.

https://www.garagejournal.com/forum/threads/quincy-air-compressor-wiring-help.353669/
 

Mzungu

Well-known member
Joined
Sep 3, 2022
Messages
176
Up here in Canada, I would run a teck cable or bx cable straight from the panel to the compressors starter box. Do you guys in the US not have a cable approved for that type of purpose?
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,994
Location
Modesto, CA
Up here in Canada, I would run a teck cable or bx cable straight from the panel to the compressors starter box. Do you guys in the US not have a cable approved for that type of purpose?
teck cable is overkill for this application...

BX doesnt exist anymore. it was replaced with AC...

MC would work just fine here..... or SER....
 

Mzungu

Well-known member
Joined
Sep 3, 2022
Messages
176
teck cable is overkill for this application...

BX doesnt exist anymore. it was replaced with AC...

MC would work just fine here..... or SER....
Teck itself is definitely an upgrade, the teck connectors themselves are overkill. In that situation I would just use a normal flex connector on it.

The brand name BX has carried on for decades after it was discontinued and the AC90 is still often referred to as BX. BX was long gone when I started back in 89.
 
To avoid these ads, REGISTER NOW!
Top Bottom