To avoid these ads, REGISTER NOW!

I lost a leg...

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
... of AC power coming into my shop?

I did some work in my detached shop last night after work, used several circuits as usual, no issues. I've never had any real electrical issues in shop, ever. No flickering lights or anything of that nature. I believe shop, most wiring, and panel are about 22 years old. Aluminum wiring feeds 100A panel. Tonight I decided to park a truck inside and unplug a battery charger quick... No ceiling lights, no ceiling fans, no compressor, no welder outlet, no 2-post lift... Half of the 110 powered circuits work fine. Propane heater works, thankfully! I yanked the panel off and checked voltage coming in to meter, one "hot" reads 0V.

I'm in Central Minnesota. It has been extremely cold lately, below -20* the last two days. Ground is very frozen. Nothing at all has happened in the yard at time of failure, nothing. No dirt work or heavy trucks, nothing.

Shop is fed from meter on house 100+ ' away. The much older home receives power from aerial lines and wiring to home is fine, all circuits and 220v appliances OK.

So there must be a problem in-between meter on home and 1 aluminum wire feeding shop. Meter box has a power company "lock" on it. Should I call them first and ask to check connections at meter socket? Meter socket is customer responsibility AFAIK.

Any guesses on what failed? Kinda dreading a wire failure = i'm screwed
 
To avoid these ads, REGISTER NOW!

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
Have the POCO come out and pull the meter to check the connections. It possible, but not probable, that the problem is there. I've been on more than one winter service call for no or partial power that turned out to be a bad underground wire. I don't recall ever having a bad meter socket connection but anything is possible.
 

The Cobbler

Super Moderator
Staff member
Joined
Oct 24, 2013
Messages
25,856
Location
Niagara Region, Ontario, Canada
A residential townhouse complex I used to work in had underground aluminum wire, it was all failing undergorund . they had several hundred feet of Teck cable strung around at any given time as jumpers until they could get a repair done . before they tendered replacing it all
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,995
Location
Modesto, CA
... of AC power coming into my shop?

I did some work in my detached shop last night after work, used several circuits as usual, no issues. I've never had any real electrical issues in shop, ever. No flickering lights or anything of that nature. I believe shop, most wiring, and panel are about 22 years old. Aluminum wiring feeds 100A panel. Tonight I decided to park a truck inside and unplug a battery charger quick... No ceiling lights, no ceiling fans, no compressor, no welder outlet, no 2-post lift... Half of the 110 powered circuits work fine. Propane heater works, thankfully! I yanked the panel off and checked voltage coming in to meter, one "hot" reads 0V.
when you say meter, what are you referring to? voltmeter?
I'm in Central Minnesota. It has been extremely cold lately, below -20* the last two days. Ground is very frozen. Nothing at all has happened in the yard at time of failure, nothing. No dirt work or heavy trucks, nothing.

Shop is fed from meter on house 100+ ' away. The much older home receives power from aerial lines and wiring to home is fine, all circuits and 220v appliances OK.

So there must be a problem in-between meter on home and 1 aluminum wire feeding shop. Meter box has a power company "lock" on it. Should I call them first and ask to check connections at meter socket? Meter socket is customer responsibility AFAIK.

Any guesses on what failed? Kinda dreading a wire failure = i'm screwed
how is the feeder to your shop connected to the main service panel @ the house? Do you have a divorced meter with dual lugs and feeder connects to meter? Or do you have a breaker or lugs in the main service panel that the feeder connects to?

is the feeder direct buried or in conduit?
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
when you say meter, what are you referring to? voltmeter?

how is the feeder to your shop connected to the main service panel @ the house? Do you have a divorced meter with dual lugs and feeder connects to meter? Or do you have a breaker or lugs in the main service panel that the feeder connects to?

is the feeder direct buried or in conduit?
I apologize, I'm tired and miss-typed. I removed the shop panel cover only, and checked voltage with a voltmeter. (NOTHING CHECKED AT METER)

I believe this must be a divorced meter with dual lugs?? Shop is not fed from house service panel.

I do not know if feeder is direct buried or in conduit. Risers above ground are in conduit obviously.

This place was purchased as-is, I do not know much about how this was set up. I directly helped install/upgrade previous home garage. A divorced meter setup was used and wiring was direct buried, looks similar above ground, but older...
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
and how old is it, soil conditions
I believe shop panel was installed in 2002-2003. Soil conditions are hard packed and very frozen. I don't understand how anything underground could move or change at all now, unless ice was affected.

I will contact power company, hopefully they can check meter connections soon-ish.
 

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
I believe shop panel was installed in 2002-2003. Soil conditions are hard packed and very frozen. I don't understand how anything underground could move or change at all now, unless ice was affected.

I will contact power company, hopefully they can check meter connections soon-ish.
It could be something as pathetic as a pebble in the backfill laying on the wire. 20+ years of freeze/thaw cycles and the movement with it and the wire gets rubbed through among other things. Keep your fingers crossed and pray it's at the meter socket.
 

mm08822

Well-known member
Joined
Jan 13, 2012
Messages
5,890
Location
NJ
It could be something as pathetic as a pebble in the backfill laying on the wire. 20+ years of freeze/thaw cycles and the movement with it and the wire gets rubbed through among other things. Keep your fingers crossed and pray it's at the meter socket.
yup, that's what I was getting at with soil conditions.......select fill can easily pay for itself.
 

mm08822

Well-known member
Joined
Jan 13, 2012
Messages
5,890
Location
NJ
So if the worst happens and a leg is open somewhere, the temporary solution may be to disconnect the failed leg at the cb in the sub-panel and jumper across both bus bars with a 2p cb and jumper. This would get all of your circuits working except for any 240vac loads.

Then plan for the repair in warmer weather. Even if you can locate the point of failure now, there may be other locations on their way. Very difficult to tell. See what a fault locator will charge and roll the dice from there.
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
19,995
Location
Modesto, CA
I don't understand how anything underground could move or change at all now, unless ice was affected.
as stated by sparky, a very small pebbly couldve nicked the insulation. 20yrs of freezing and thawing can cause contraction and expansion. eventually the insulation wears thru, water gets into the aluminum wire (or copper) and it eventually turns into a white toothpaste like substance.... once all strands are lost, you lose voltage potential in the subpanel.

repair gonna be a pain right now.

If you have to run a new feeder and current one is direct burial, I would switch to underground conduit.... cheap insurance
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
Welp, power company came out almost immediately (wow) after I made an online report of "partial" outage to outbuilding and they checked socket connections. Guys said they look fine. Also said not surprised to see an open leg and asked if direct buried... Very impressed with power co service but a bit crushed that my home shop is half down, for awhile. Bus bar jumper sounds like a good temp option to get lights back on.

Thank you guys for your advice. I really appreciate it.
 

Bert_

Well-known member
Joined
Dec 24, 2016
Messages
9,716
Location
NW Iowa
I had a guy with a bad underground wire to a pig nursery last month. Normally I don't see underground fail in the dead of winter.

I tried a few times and couldn't get my underground fault locator to find it. Best I could do was string a wire 300' across the ground. I'll locate it and repair it in the spring.
 

Stuart in MN

Well-known member
Joined
Sep 8, 2005
Messages
23,063
Location
Minneapolis
Welp, power company came out almost immediately (wow) after I made an online report of "partial" outage to outbuilding and they checked socket connections. Guys said they look fine. Also said not surprised to see an open leg and asked if direct buried... Very impressed with power co service but a bit crushed that my home shop is half down, for awhile. Bus bar jumper sounds like a good temp option to get lights back on.
Out of curiosity, who is your service provider? I'm a retired electrical engineer, when I was still working I interacted with most of the electric utilities in the state on a regular basis. Some were very responsive, others not so much...
Rather than jumpering both legs together, I'd suggest moving some individual circuits on the dead side to the live side and/or rearranging some of the circuit breakers. Be careful with trying to run everything on one leg so you don't overload it.
 

PCustoms

Well-known member
Joined
Jul 23, 2011
Messages
22,575
Location
VT
Rather than jumpering both legs together, I'd suggest moving some individual circuits on the dead side to the live side and/or rearranging some of the circuit breakers. Be careful with trying to run everything on one leg so you don't overload it.

That accomplishes the same thing and is more work. Why?
 

Bert_

Well-known member
Joined
Dec 24, 2016
Messages
9,716
Location
NW Iowa
Will need both ends of the bad wire disconnected anyway at some point when it gets a fault locator hooked to it
 

Stuart in MN

Well-known member
Joined
Sep 8, 2005
Messages
23,063
Location
Minneapolis
He should disconnect them at both ends...
I agree, but it was said the workshop wiring was connected to lugs in the meter at the house - maybe I missed it, but I didn't see mention of a disconnect switch there, so it would be unsafe for him to work on an energized connection.
 
To avoid these ads, REGISTER NOW!

PCustoms

Well-known member
Joined
Jul 23, 2011
Messages
22,575
Location
VT
I agree, but it was said the workshop wiring was connected to lugs in the meter at the house - maybe I missed it, but I didn't see mention of a disconnect switch there, so it would be unsafe for him to work on an energized connection.
I suspect meter main, but yeah, you could be correct
 

mm08822

Well-known member
Joined
Jan 13, 2012
Messages
5,890
Location
NJ
Worst case if the previously suggest temp later fails, buy your conductors (extra long) aand layout as Bert did.
Obviously, this only works if they won't be damaged in the interim.
 

KenC

Well-known member
Joined
Dec 20, 2009
Messages
2,578
... of AC power coming into my shop?

I did some work in my detached shop last night after work, used several circuits as usual, no issues. I've never had any real electrical issues in shop, ever. No flickering lights or anything of that nature. I believe shop, most wiring, and panel are about 22 years old. Aluminum wiring feeds 100A panel. Tonight I decided to park a truck inside and unplug a battery charger quick... No ceiling lights, no ceiling fans, no compressor, no welder outlet, no 2-post lift... Half of the 110 powered circuits work fine. Propane heater works, thankfully! I yanked the panel off and checked voltage coming in to meter, one "hot" reads 0V.

I'm in Central Minnesota. It has been extremely cold lately, below -20* the last two days. Ground is very frozen. Nothing at all has happened in the yard at time of failure, nothing. No dirt work or heavy trucks, nothing.

Shop is fed from meter on house 100+ ' away. The much older home receives power from aerial lines and wiring to home is fine, all circuits and 220v appliances OK.

So there must be a problem in-between meter on home and 1 aluminum wire feeding shop. Meter box has a power company "lock" on it. Should I call them first and ask to check connections at meter socket? Meter socket is customer responsibility AFAIK.

Any guesses on what failed? Kinda dreading a wire failure = i'm screwed
Sorry to hear that. I was hoping that you would find the same as I've had three times now. The "fuse" on one of the 3 conductors, (3ph service) line to transformer, had tripped. In all one case there was a dead squirrel at the foot of the pole, the other two were during some lightning storms. Watching the guys manipulate that 25' 'hot stick' to replace them from the ground is something.
 

Norcal

Well-known member
Joined
Mar 16, 2008
Messages
13,753
as stated by sparky, a very small pebbly couldve nicked the insulation. 20yrs of freezing and thawing can cause contraction and expansion. eventually the insulation wears thru, water gets into the aluminum wire (or copper) and it eventually turns into a white toothpaste like substance.... once all strands are lost, you lose voltage potential in the subpanel.

repair gonna be a pain right now.

If you have to run a new feeder and current one is direct burial, I would switch to underground conduit.... cheap insurance
Not so cheap anymore but still cheaper then digging things up to to replace a failed feeder.
 

driftpin

Well-known member
Joined
Dec 22, 2016
Messages
11,221
Location
Miami-Dade/Broward Co. Florida
I have an above-ground aerial service to the weatherhead in my FL SFR (single family residence) & a detached 1-car garage w/a 100 1 Ph service, fed from the meter can/main disconnect box to the 1-car garage 100 amp service in EMT. I did it in UG conduit just for the ease of replacement of wires, if that was ever needed. It's about a 50 ft separation, so say 60 ft end-to-end. The connection at the garage is outside and is a disconnect. Inside the garage is the 100 amp circuit panel, and a variety of 120V and 240V circuits. I have 30 amp 240V for a 240V air compressor and another for a 120/240V multi-process welder. Only pne 240V at a time, operates.

I bet the OP will end-up running a temporary 240V until the ground thaws. And I bet he does it in conduit of one type or another.
 

PCustoms

Well-known member
Joined
Jul 23, 2011
Messages
22,575
Location
VT
I bet the OP will end-up running a temporary 240V until the ground thaws. And I bet he does it in conduit of one type or another.

If it was me I'd run the conduit long on the surface, run the wire long in the conduit and hook-up.

When the ground thaws trench, pull the wire back enough (leaves pull rope on it) to cut and finish the conduit on each end then pull it back into panel and terminate. Probably not 100% to code but sometimes you have to do what you can...
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
Out of curiosity, who is your service provider? I'm a retired electrical engineer, when I was still working I interacted with most of the electric utilities in the state on a regular basis. Some were very responsive, others not so much...
Rather than jumpering both legs together, I'd suggest moving some individual circuits on the dead side to the live side and/or rearranging some of the circuit breakers. Be careful with trying to run everything on one leg so you don't overload it.
Minnesota Power. Very unlikely that our previous power co. would have stopped by that quick.

"Break" or problem spot is intermittent. Saturday, shop functioned as if nothing happened. I had 122v at problem leg, 125v on the other. Today, dead again (0v).
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
If it was me I'd run the conduit long on the surface, run the wire long in the conduit and hook-up.

When the ground thaws trench, pull the wire back enough (leaves pull rope on it) to cut and finish the conduit on each end then pull it back into panel and terminate. Probably not 100% to code but sometimes you have to do what you can...
Unfortunately I can't really run anything temporarily on the surface, as its mostly all my driveway. Snowplow literally scraped it off yesterday.

My thoughts are to hopefully have "break" located late spring? Dig it up and inspect? If it can be repaired, great... If not, OK, will do whatever is a proper fix. I need this taken care of, but I realize it will likely have to wait.

I may just continue to use power as is, intermittently? I don't see it damaging anything at this point, all affected loads are OFF.
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
I've never seen an underground aluminum wire fail intermittently. Goes bad and stays that way. Maybe it can happen but I would triple check for other issues.
I also find this odd? I will probably check meter connections myself, although I shouldn't have any reason do doubt power company techs. I don't believe there are any other accessible connections, aside from the shop panel itself. Connections are tidy and tight there. ???
 

Bert_

Well-known member
Joined
Dec 24, 2016
Messages
9,716
Location
NW Iowa
Unfortunately I can't really run anything temporarily on the surface, as its mostly all my driveway. Snowplow literally scraped it off yesterday.

My thoughts are to hopefully have "break" located late spring? Dig it up and inspect? If it can be repaired, great... If not, OK, will do whatever is a proper fix. I need this taken care of, but I realize it will likely have to wait.

I may just continue to use power as is, intermittently? I don't see it damaging anything at this point, all affected loads are OFF.
Spring is good. My fault finder works best when the ground is moist.

Fixing a bad underground wire is no big deal. If a guy comes prepared I've had them dug up and fixed in an hour. That's ideal conditions.
 

bronc076

Well-known member
Joined
Jul 17, 2023
Messages
190
Location
Ozarks
If you are pumping power into the earth due to a bad wire you may notice that on your electric bill. At my place in AR I lost a phase to the detached garage due to an underground failure. The place is unoccupied when I'm not there and I had wondered why the electric bill had gone up. Fixing the problem brought the electric bill back to where it belonged.

The intermittent phase should be disconnected at the meter by your POCO If it's known for sure the problem is underground. You sure there is not a disconnect on the outside of the building, or a splice in a box somewhere you may not be aware of? Some people switch from direct burial to cable that's permitted indoors like SER or THHN for code reasons.
 
Last edited:

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
This is a long shot, but when you checked the voltages, were you on the lug or the wire? I really doubt it's a bad connection at the shop panel but it's nothing to verify. When the power goes out, check the wire feeding the breaker, not just on the lug itself.
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
This is a long shot, but when you checked the voltages, were you on the lug or the wire? I really doubt it's a bad connection at the shop panel but it's nothing to verify. When the power goes out, check the wire feeding the breaker, not just on the lug itself.
Checked at lug and wire at lug, was at 0v via my cheapish handy multimeter today. Yesterday, was at 121.5-122v and all was working normal. Opposite feeder was and still is at 125v.
 

sparky 1971

Well-known member
Joined
Oct 9, 2018
Messages
7,967
Location
Central Iowa
Checked at lug and wire at lug, was at 0v via my cheapish handy multimeter today. Yesterday, was at 121.5-122v and all was working normal. Opposite feeder was and still is at 125v.
Then that is eliminated. How is it connected at the meter? Does it have two sets of lugs or are the house and garage both stuffed under the same one? You would have had to seen it when the POCO was out and opened it up, so you may not know.
 
OP
X

xjfish

Well-known member
Joined
Feb 22, 2014
Messages
1,290
Then that is eliminated. How is it connected at the meter? Does it have two sets of lugs or are the house and garage both stuffed under the same one? You would have had to seen it when the POCO was out and opened it up, so you may not know.
I do not know, was trying to get some shut eye when they were here. It was late and they didn't spend much time... I will probably open lid and perhaps snap a pic this week if I get time. I am also curious. Don't call the PowCo police. :shocking:
 
To avoid these ads, REGISTER NOW!
Top Bottom