Testing 110V wiring to garage, unknown wiring

[Lil'John]

I've got a garage that was built in the 70s or earlier that is detached from a 1940s house(~30 feet from house to garage).

The wiring in it was a mess but I didn't think the wiring to it was as bad.

It has three or more power sources coming into the garage

The 220V circuit works fine with 2 hots and a ground.

But it has three misc wires(singles with no real color coding to it) and a 14/2 romex coming in are unknown

I pulled the old rats nest wiring out that was working but no idea how.

I tried to tie in one of my new 110V circuits (12/2) to the 14/2 romex and it didn't work. The one circuit was just four outlets.

So the question is how do I check the romex and three misc wires to see if they are 110V, neutral, or grounds?

I plan to head to Home Depot for a volt meter(mine died before moving into house) Anything else I should grab?

 

[wyliesdiesels]

I would also grab an outlet tester and an inductive voltage tester!!

http://www.homedepot.com/p/Klein-Tools-GCFI-Receptacle-Tester-RT200/203195019

http://www.homedepot.com/p/Klein-Tools-Dual-Range-Non-Contact-Voltage-Tester-NCVT-2/203391692

As far as testing goes, the inductive tester will ONLY pickup hot wires. Use the voltmeter to check for voltage, then if u get no reading, test for continuity.

A detached structure should not have more than one source of power. SOunds like u have a mess to clean up! I would ditch all the old power feeds and put in a new feeder and subpanel!

 

[Lil'John]

I would also grab an outlet tester and an inductive voltage tester!!

http://www.homedepot.com/p/Klein-Tools-GCFI-Receptacle-Tester-RT200/203195019

http://www.homedepot.com/p/Klein-Tools-Dual-Range-Non-Contact-Voltage-Tester-NCVT-2/203391692

As far as testing goes, the inductive tester will ONLY pickup hot wires. Use the voltmeter to check for voltage, then if u get no reading, test for continuity.

Sadly my local homedepot doesn't have either of the above in stock

For the volt meter testing, can I use the ground out of the known good 220V wiring to find out which of the other wires are 110V?

How would I use a volt meter to check if a wire is a neutral?

A detached structure should not have more than one source of power. SOunds like u have a mess to clean up! I would ditch all the old power feeds and put in a new feeder and subpanel!

You have hit a known problem that I'm trying to limp along just a little longer. I intend to enlarge the garage shortly(next summer) Right now at 20'x14', it is very tight with a car and washer/dryer in it.

 

[wyliesdiesels]

Sadly my local homedepot doesn't have either of the above in stock

For the volt meter testing, can I use the ground out of the known good 220V wiring to find out which of the other wires are 110V?

How would I use a volt meter to check if a wire is a neutral?

You have hit a known problem that I'm trying to limp along just a little longer. I intend to enlarge the garage shortly(next summer) Right now at 20'x14', it is very tight with a car and washer/dryer in it.

Yes, u can use the ground prong on the known 240 outlet to check other outlets. But first, i would make sure that the ground is hooked up by testing hot to ground on the outlet. What type of outlet is it?

As far as testing for neutral, if all these feeds go back to the main service panel, neutral and ground wires will be at the same potential so theres no way to check with a voltmeter.

Do they at least have the same types of testers in a different brand?

 

[Lil'John]

Yes, u can use the ground prong on the known 240 outlet to check other outlets. But first, i would make sure that the ground is hooked up by testing hot to ground on the outlet. What type of outlet is it?

As far as testing for neutral, if all these feeds go back to the main service panel, neutral and ground wires will be at the same potential so theres no way to check with a voltmeter.

Do they at least have the same types of testers in a different brand?

The outlet is listed as a Leviton 30 Amp 2-Pole Flush-Mount Single Outlet-Black:
http://www.homedepot.com/p/Leviton-...-000/202077700?N=c33aZwcZ1z13nok#.UmNAp3nn-wU

The outlet looks like this(sorry for oversize):

 

[wyliesdiesels]

That is a non grounding recepticle but for testing purposes it doesnt matter.

 

[Bib Overalls]

Post a picture of the sub-panel.

Are your walls open or closed?

Is the service from the house overhead or underground? If it is overhead can you count the number of cables.

14/2 may be a lighting circuit.

The white wire from the main panel should be terminated at the neutral bus bar. It may be black and it may be a smaller gauge that the feed wire. Since everything works I would assume they are terminated correctly.

Since your garage was built in 1970, or so, you may or may not have a fourth green or bare wire wire from the main panel terminated on a separate ground bus.

You should have a bare #6 wire that terminates on the ground bus that comes from a grounding rod. If you don't have a separate ground bus bar the bare #6 should terminate at the neutral bus. If you don't have a separate ground bus, a #6 bare copper wire to ground, or a fourth green or bare wire from the main panel in your sub-panel the all your garage grounds are through the neutral wire to the house. I don't recall when the code was changed to require a separate/fourth conductor to sub-panels but I think a detached structure require a separate ground rod in 1970.

It is quite possible your 1940s house was wired with out any ground wires or a ground rod! Just a bond wire from the main panel neutral bus to the nearest cold water line. A quick way to confirm this is to look at an outlet. Will it accommodate a three prong plug? If no, you don't have a separate ground in the house and may not have one in the garage. If you have screw in fuses in your main panel I can almost guarantee you do not have grounds. Not improper when built but not code today.

Back at your garage the simplest way to determine the function of your mystery wires is to leave them unterminated and see what does not work.

Your mystery 14/2 cable should have a black, white, and possibly a bare copper wire. The black goes to a 15 amp breaker, the white goes to neutral, and the bare copper goes to the grounding bus if one is present and to the neutral bus if not. You know that, of course, but I'm feeling verbose tonight.

Older houses have a variety of electrical quirks that code changes have eliminated in newer construction. A short could make the water taps tingle and, over time, water supply pipes in the house and the service lines could be eaten away by cathodic action.

More than you asked for. Hopefully I did not confuse you. Good luck

 

[wyliesdiesels]

Post a picture of the sub-panel.

Are your walls open or closed?

Is the service from the house overhead or underground? If it is overhead can you count the number of cables.

14/2 may be a lighting circuit.

The white wire from the main panel should be terminated at the neutral bus bar. It may be black and it may be a smaller gauge that the feed wire. Since everything works I would assume they are terminated correctly.

Since your garage was built in 1970, or so, you may or may not have a fourth green or bare wire wire from the main panel terminated on a separate ground bus.

You should have a bare #6 wire that terminates on the ground bus that comes from a grounding rod. If you don't have a separate ground bus bar the bare #6 should terminate at the neutral bus. If you don't have a separate ground bus, a #6 bare copper wire to ground, or a fourth green or bare wire from the main panel in your sub-panel the all your garage grounds are through the neutral wire to the house. I don't recall when the code was changed to require a separate/fourth conductor to sub-panels but I think a detached structure require a separate ground rod in 1970.

It is quite possible your 1940s house was wired with out any ground wires or a ground rod! Just a bond wire from the main panel neutral bus to the nearest cold water line. A quick way to confirm this is to look at an outlet. Will it accommodate a three prong plug? If no, you don't have a separate ground in the house and may not have one in the garage. If you have screw in fuses in your main panel I can almost guarantee you do not have grounds. Not improper when built but not code today.

Back at your garage the simplest way to determine the function of your mystery wires is to leave them unterminated and see what does not work.

Your mystery 14/2 cable should have a black, white, and possibly a bare copper wire. The black goes to a 15 amp breaker, the white goes to neutral, and the bare copper goes to the grounding bus if one is present and to the neutral bus if not. You know that, of course, but I'm feeling verbose tonight.

Older houses have a variety of electrical quirks that code changes have eliminated in newer construction. A short could make the water taps tingle and, over time, water supply pipes in the house and the service lines could be eaten away by cathodic action.

More than you asked for. Hopefully I did not confuse you. Good luck

woa....I dont think u read the previous posts. There is no subpanel in the garage.

And just because there is 3 prong outlets, it doesnt mean theyre grounded! Anyone could replace a 2 prong with a 3 prong despite there being no EGC...

 

[Lil'John]

Bib, thanks for all the info.

The garage has almost none of the old wiring. The old wiring coming to the garage is in an open wall.

From the main panel to the garage in three underground conduits are four sets of wires(yes, this is NOT code):

1. 220V set - This is three separate wires. It is known to be good as they were hooked directly to the plug shown above. In conduit #1
2. 3 or 4 mystry wires. I have not checked gauge. There is a white, red, black, and I think a forth of unknown. In conduit #1 with the 220V set.
3. 14/2 romex. In conduit #2
4. two 14/2 romex in conduit #3. These are for a light switch and exterior light on the garage. They are part of a circuit that includes three lights on the house, one switch in the house, one light on the garage, and one switch in the garage.

The mystery wires and 14/2 romex were used to power:

• Washer outlet
• garage door opener outlet
• 2 lights

The wiring was beyond odd. Some of the misc wires and the 14/2 romex went to the washer outlet. Yes, some of ALL of the wires were in the back of the washer outlet. No, the tabs were not broken off of the outlet to separate plugs. I'll see if I can get a picture of the plug and some of the wire.

I was going to have two 110V circuits in the garage:

1. Four 110V outlets
2. Two work bench lights, washer, garage door opener, and two regular lights

 

[Lil'John]

Here are two pictures showing the "mess" before I pulled most of it out.

First picture shows the power coming in:

• Circled in green is the good dryer outlet
• Beside the green is the misc wires: black, red, and white.
• Pointed in light blue is the pair of romex for outdoor lighting
• Pointed in red is the "power" 14/2

The misc wires are wire nutted in the box with the 220V dryer and then routed up the conduit into the outlet box. In the outlet box, some of the misc wires are connected to the outlet showing in addition to the "power" romex shown going in.

 

[2ManyProjects]

Bib, thanks for all the info.

The garage has almost none of the old wiring. The old wiring coming to the garage is in an open wall.

From the main panel to the garage in three underground conduits are four sets of wires(yes, this is NOT code):

The wiring was beyond odd. Some of the misc wires and the 14/2 romex went to the washer outlet. Yes, some of ALL of the wires were in the back of the washer outlet. No, the tabs were not broken off of the outlet to separate plugs. I'll see if I can get a picture of the plug and some of the wire.

I am not completely convinced that you have correctly identified all of those wires; and based in part on our previous discussions of this cluster-fsck of ad-hoc DIY add-ons (http://www.garagejournal.com/forum/showthread.php?t=215691 and http://www.garagejournal.com/forum/showthread.php?t=216610), I'm guessing that at least SOME of them go to (or come from) that "shed" you spoke of earlier.

I was going to have two 110V circuits in the garage:

1. Four 110V outlets
2. Two work bench lights, washer, garage door opener, and two regular lights

I have a better idea.

How far away is the nearest coin-op laundromat? You've already stated that within six months or so, you're going to tear down ALL of this mess, (or at least close enough to "ALL" as to effectively be the same thing). If you (or perhaps more importantly, your wife) can live without the washer & dryer until that time, then BY FAR the easiest, simplest, cheapest, and SAFEST course of action is to simply disconnect everything which doesn't work correctly, and even the "apparently working" stuff, if it looks too horridly kludged to live with -- and leave it disconnected until such time as you can re-do it from scratch (presumably as part of the garage rebuild project), and thus be SURE that it's done right.

Any "temporary jury rigs" you make now, will necessarily be based on GUESSING which wire goes where. And even if you guess correctly, the usability and safety of whatever you tack on now will still be dependent on how well all that old stuff was installed (which I'd call "not very", based on both your descriptions and the pics), AND whatever the current condition of all that old stuff (especially in places you CAN'T see, such as those underground conduits) might be. All in all, it's a huge **** shoot -- and given the timing involved, that's a gamble that is just not worth taking.

Wait until you can do the job RIGHT, and do it ONCE.

 

[Lil'John]

I am not completely convinced that you have correctly identified all of those wires; and based in part on our previous discussions of this cluster-fsck of ad-hoc DIY add-ons (http://www.garagejournal.com/forum/showthread.php?t=215691 and http://www.garagejournal.com/forum/showthread.php?t=216610), I'm guessing that at least SOME of them go to (or come from) that "shed" you spoke of earlier.

Winner answer The 14/2 romex actually goes to that shed.

The heavier stuff is definitely the dryer.

Once I identified the romex, the other three(red, black, and white) are a 110V, 110V, and neutral.

I have a better idea.

How far away is the nearest coin-op laundromat? You've already stated that within six months or so, you're going to tear down ALL of this mess, (or at least close enough to "ALL" as to effectively be the same thing). If you (or perhaps more importantly, your wife) can live without the washer & dryer until that time, then BY FAR the easiest, simplest, cheapest, and SAFEST course of action is to simply disconnect everything which doesn't work correctly, and even the "apparently working" stuff, if it looks too horridly kludged to live with -- and leave it disconnected until such time as you can re-do it from scratch (presumably as part of the garage rebuild project), and thus be SURE that it's done right.

Any "temporary jury rigs" you make now, will necessarily be based on GUESSING which wire goes where. And even if you guess correctly, the usability and safety of whatever you tack on now will still be dependent on how well all that old stuff was installed (which I'd call "not very", based on both your descriptions and the pics), AND whatever the current condition of all that old stuff (especially in places you CAN'T see, such as those underground conduits) might be. All in all, it's a huge **** shoot -- and given the timing involved, that's a gamble that is just not worth taking.

Wait until you can do the job RIGHT, and do it ONCE.

Point taken and we did so the other day when water company killed a water main. For two loads, it was close to $12 So from a "cheaper" standpoint, not quite

From a time/ease standpoint, beating my head on cleanup is my therapy from work.

While my plan still stands for ripping it apart this summer, some things aren't falling into line as I'd like so I may be stuck a little longer than liked

 

[RickP]

Sounds like you could hook this garage up temporarily until you can build a new garage, and it wouldn't be that hard to fix. If you've already got red/black/white wires run, then you could install a sub panel pretty easily. A small panel is pretty cheap, or you could use a bigger panel now, then move it to the new garage when it's finished.

Even if you don't have ground rods, do you have metal water pipes in the garage? Grounding the subpanel to a water pipe might not be up to current code, but it would work for now.

Using the wires feeding the garage now wouldn't meet code, because you have multiple circuits in a detached building, but you could fix it by pulling new larger wires to the subpanel and abandoning the old wires.


Posted from Garagejournal.com App for Android

 

[wyliesdiesels]

Here are two pictures showing the "mess" before I pulled most of it out.

First picture shows the power coming in:

• Circled in green is the good dryer outlet
• Beside the green is the misc wires: black, red, and white.
• Pointed in light blue is the pair of romex for outdoor lighting
• Pointed in red is the "power" 14/2

The misc wires are wire nutted in the box with the 220V dryer and then routed up the conduit into the outlet box. In the outlet box, some of the misc wires are connected to the outlet showing in addition to the "power" romex shown going in.

What a fricken MESS!!

 

[Lil'John]

Sounds like you could hook this garage up temporarily until you can build a new garage, and it wouldn't be that hard to fix. If you've already got red/black/white wires run, then you could install a sub panel pretty easily. A small panel is pretty cheap, or you could use a bigger panel now, then move it to the new garage when it's finished.

Even if you don't have ground rods, do you have metal water pipes in the garage? Grounding the subpanel to a water pipe might not be up to current code, but it would work for now.

Using the wires feeding the garage now wouldn't meet code, because you have multiple circuits in a detached building, but you could fix it by pulling new larger wires to the subpanel and abandoning the old wires.

I have been strongly considering doing a "temp" panel. What I have been told by one electrician is I can run a panel to my current shed and then use some "special" conduit to run ALL the individual circuits in this single conduit to the garage(~2 foot between the4 two structures)

On the water, unfortunately it is PVC. And only cold water a that.

No question on the current multi-circuit setup not being to code. Not overly amused with it.

What a fricken MESS!!

That is only the tip of the iceberg. I still need to crawl under the house and fix the electrical under there.

I haven't gotten fully under there yet. But from what I've seen, there is at least 3 unsecured wires under there spanning 5+ feet

 

[RickP]

It sounds like your best bet would be to add a subpanel and two ground rods. You'll need to add the ground rods when you upgrade anyway, so you might as well do it now.

You could re-purpose one of the mystery wires as the ground from the main panel, as long as it's sized correctly and in conduit #1 with the other 240v wires.