Strange (to Me) Wiring In Garage - Electrical - DIY Chatroom Home Improvement Forum
Advertisement


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

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

Reply
 
Thread Tools
Display Modes
Old 06-06-2010, 10:26 PM   #1
Newbie
 
Join Date: Jun 2010
Location: Plymouth MI
Posts: 23
Rewards Points: 10
Default

strange (to me) wiring in Garage


Garage is detached. Wire run through conduit back to house. In conduit is a thin gauge wire with a 3 prong plug (house side) and direct wired into a junction box w/outlets in the garage. There is also a 15 amp 'sub' box in the garage that seems to be disconnected fed by a 10awg wire coming directly from the house panel. When I had the panel in the house off today there were 3 wires coming from the 10awg Black/Red in a standard 220 config on a dual 20amp breaker and what I swear was a green wire (same gauge) conected to a different 15amp single pole.

Is this some goofy 3 phase set up I have never seen (amatuer)? House was built in the 20's, but the electrical seems to have been upgraded in the BX era.
jgold47 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 06-06-2010, 10:36 PM   #2
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Rewards Points: 2,000
Default


Where are you located ?



Scuba_Dave is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 06-06-2010, 10:37 PM   #3
Newbie
 
Join Date: Jun 2010
Location: Plymouth MI
Posts: 23
Rewards Points: 10
Default


SE michigan
jgold47 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 06-07-2010, 06:23 AM   #4
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 8,597
Rewards Points: 2,800
Default


The green wire must be taken off of the single pole breaker and connected to the ground bus bar (or terminal strip). Wire nut on a short length (pigtail) of green or bare wire if it does not reach.

If there is no white wire in the 10 gauge cable or cluster then only 240 volts can be run to the garage that way. And it is not proper to have a second feed taken from the classifications: 120 or 240 or 120/240, as in the thin gauge wires, running between the same two buildings (house and garage here).

For 120 volts you may choose to disconnect the 10 gauge wires (with no white) completely and use just the thin gauge wires.

For 120 and 240 volts usage you may be able to string new wires (waterproof rated) through the conduit, removing the thin gauge wires as you pull. You need four: white, bare/green, and most folks use red and black for the other two. It is possible that the size of the conduit limits you to 10 gauge (240 volts @ 30 amps) or even 12 gauge (240 volts @ 20 amps). You must take these all the way to the panel and connect the red and black to opposite sides of the 120/240 volt service using a double wide breaker.

It is rare to find full 3 phase in individual homes in a residential area. But if you do have 3 phase, you can run that to your garage with red, blue, black, green, and white wires all in the same conduit getting three allotments* of 120 volts (at 30 amps for 10 gauge wires) all sharing one (white) neutral. Here you need a triple wide breaker positioned in the panel to span all three phases.

* If you draw just 20 amps of 120 volts from one leg or phase, you may not draw 40 amps from another leg on the 10 gauge wire 30 amp 240 volt circuit (208 volt if symmetric 3 phase with neutral).
__________________
Stick to your lawn watering schedule until it really starts to pour. After the storm you have only the same number of rest days you always had and then you need to start watering again.

Last edited by AllanJ; 06-07-2010 at 06:53 AM.
AllanJ is offline   Reply With Quote
Old 06-07-2010, 06:39 AM   #5
Master Electrician
 
Join Date: Mar 2010
Location: Indiana
Posts: 4,413
Rewards Points: 5,082
Default


Quote:
Originally Posted by AllanJ View Post
The green wire has to be taken off of the single pole breaker and connected to the ground bus bar (or terminal strip).

If there is no white wire in the 10 gauge cable or cluster then only 240 volts can be run to the garage. It is not proper to have a second feed of any of the classifications: 120 or 240 or 120/240, as in the thin gauge wires, running between the same two buildings (house and garage here).

For 120 volts you may choose to disconnect the 10 gauge wires completely and use just the thin gauge wires.

For 120 and 240 volts usage you may be able to string new wires (waterproof rated) through the conduit. You need white, bare/green, and most folks use red and black for the other two. It is possible that the size of the conduit limits you to 10 gauge (240 volts @ 30 amps) or even 12 gauge (240 volts @ 20 amps). You must take these all the way to the panel and connect the red and black to opposite sides of the 120/240 volt service using a double wide breaker.
You cannot tell someone this without knowing the situation. While a green wire is to be used only as a grounding conductor obviously some fool used it as a hot conductor.Although unlikely in this case, it could be a hot for a critical circuit. The whole scenario must be understood before simply telling someone to put a wire somewhere else.
brric is offline   Reply With Quote
Old 06-07-2010, 07:09 AM   #6
Newbie
 
Join Date: Jun 2010
Location: Plymouth MI
Posts: 23
Rewards Points: 10
Default


The 'green' wire in question a a pale green, fully insulated and the same gauge as the other wires in the romex. I dont recall now if there was separate neutral (I assume there is) but this was ungrounded cable. I am going to remove the thin gauge and re hook up the sub box to this goofy config once I figure it out. At some point I will run back new romex and a new mains panel in the garage as part of a remodel. Just curious why I would have 3 hot wires running. is it possible someone was trying to do a 240 + a separate 120 feed to individual circuits? Also, does anyone recall a 4 wire from the 50/60's that would have had this third wire (not a ground)
jgold47 is offline   Reply With Quote
Old 06-07-2010, 07:09 AM   #7
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 12,413
Rewards Points: 3,662
Default


Unfortunately for the OP this sounds like some cobbled together mess that needs a complete evaluation and corrections. It sounds like the outbuilding may be served by more than 1 circuit and it did not sound like there was a disconnect either. I also get the impression that a cord cap has been installed on either NM or UF, which would also be incorrect.

With problems like this i think it might be time to make a phone call.
__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.
Jim Port is online now   Reply With Quote
Old 06-07-2010, 07:11 AM   #8
Newbie
 
Join Date: Jun 2010
Location: Plymouth MI
Posts: 23
Rewards Points: 10
Default


Quote:
Originally Posted by Jim Port View Post
Unfortunately for the OP this sounds like some cobbled together mess that needs a complete evaluation and corrections. It sounds like the outbuilding may be served by more than 1 circuit and it did not sound like there was a disconnect either. I also get the impression that a cord cap has been installed on either NM or UF, which would also be incorrect.

With problems like this i think it might be time to make a phone call.

Already coming (if he would return my calls) to change out the main service panel and clean up some of the wiring. Just thought I would ask here since its bugging me.
jgold47 is offline   Reply With Quote
Old 06-07-2010, 09:53 AM   #9
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 8,597
Rewards Points: 2,800
Default


Quote:
Originally Posted by jgold47 View Post
The 'green' wire in question a a pale green, fully insulated and the same gauge as the other wires in the romex. I dont recall now if there was separate neutral (I assume there is) but this was ungrounded cable.)
For Romex cables except some of the very large sizes the ground conductor is the same gauge as the other conductors.

For running separate conductors, for the smaller gauges I think 8 and smaller, you run a ground conductor the same size as the other conductors.

You may double check to see if the pale green wire was really white at some time in the past. Perhaps sand the surface of the insulation slightly. If it is moldy it may well be too deteriorated to continue using.
__________________
Stick to your lawn watering schedule until it really starts to pour. After the storm you have only the same number of rest days you always had and then you need to start watering again.
AllanJ is offline   Reply With Quote
Old 06-07-2010, 09:59 AM   #10
Newbie
 
Join Date: Jun 2010
Location: Plymouth MI
Posts: 23
Rewards Points: 10
Default


Quote:
Originally Posted by AllanJ View Post
For Romex cables except some of the very large sizes the ground conductor is the same gauge as the other conductors.

For running separate conductors, for the smaller gauges I think 8 and smaller, you run a ground conductor the same size as the other conductors.

You may double check to see if the pale green wire was really white at some time in the past. Perhaps sand the surface of the insulation slightly. If it is moldy it may well be too deteriorated to continue using.
Possible - but why hook up the neutral to 15amps?
jgold47 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools
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
Wiring Main-Breaker Box in Detached Garage wstribl Electrical 15 05-11-2013 05:15 PM
Underground Wiring From House to Garage Virginhomeowner Electrical 7 05-21-2010 10:53 PM
Wiring a garage reverendcolin Electrical 34 11-10-2008 04:53 PM
Enhancing existing wiring to detached garage justinperkins Electrical 46 07-07-2008 07:29 PM
wiring 220 in garage maberry72 Electrical 1 03-12-2006 11:45 AM




Top of Page | View New Posts