Subpanel fed from single conductor

[MVWSR]

So im trying to help my GrandMother & Mom with a subpanel(b) issue in a detached garage. They mentioned the golf cart stopped charging after sometime recently but cant pinpoint exactly when. Everything is 110 in this garage. And all the lights work.
Im thinking it is a result of recently construction/electrical work, somehow damaged or dropping the neutral.

So what i know is the house had its subpanel(a) moved. Flipping from previously, inside the half bath, to the otherside of the wall making it in the garage. (attached garage)
The location of the 2pole breaker previously tagged "shop" has been made to the new air handler in the garage. trying find the new source for the detached shop I found a single #2 spliced outside the panel to a #10 going into an open KO. This is a single pole 20. The subpanel(b) at the detached garage has #2 mhf in conduit ,LB , with 1 leg isolated(not connected) and #6 EGC from a ground rod just outside.
I can see the detached subpanel(b) is floating neutral with the neutrals & grounds bonded in the same buss. Im measuring full current on ground conductor 1.7A with lights, trying to spin up the grinder, i found the clamp at the ground rod arc'n&spark'n. I couldn't get to it with the flathead to tighten, so I changed it out. No fix.

The charger works from another outlet at the attached garage. I also found when trying to use a bench grinder, the lights started brownout. So as it is ,low current LED's and other 110 devices work, but the high current loads expose the problem this subpanel circuit cant handle the load.

To summarize, main has 100a 2pole going to the attached garage subpanel(a), feeding detached garage subpanel(b) with a single conductor. Both subpanels the neutrals, grounds are improper bonded. The last subpanel in the detached garage has just single leg, no neutral that i can find feeding it. How tf? I mean i think I know how its working (kinda) but how to? Lol

 

[MVWSR]

Forgot to mention, I put a locator on the open conductor and neutral conductor from subpanel(b) it crosses paths with a new gas line for a new hot water heater. I didnt dig in those locations, but I did find a single #2 coming from the dirt into the attached garage coming from the source subpanel(a). Digging at that I found a splice, atleast a tape job coming out of a 1" iron pipe. It was raining abit and its being my last day here i didnt want to get any deeper into exploration. I cant say if the tape is as fresh as the recent rehab project , but the iron pipe is well rusted and too small to have had all 3 of the mhf that I find in the LB at the detached garage. Its possible when the did the gas, they did some fix before anyone home realized it, I guess ill have to spot hole it a few times along the new trench to see if I see the 2" pvc with the mhf .unfortunately thats gotta wait until I comeback in April or July.

 

[PCustoms]

Need pics of the faulty sub panel with the cover off

 

[MVWSR]

I cant get them. But like I said, at the detached garage subpanel(b) the mhf- 1 leg is hot and landed, 1 is taped and isolated. The neutral is landed on the common ground buss with #6 EGC. Ive got full current flow on the #6, matching the hot leg. *no current flow on the neutral because its open

 

[mike93lx]

Rip it out (or abandon in place) and install a new feeder.

I'd tell them to stop using it and shut the breaker off. Running an extension cord for the time being would be safer

 

[MVWSR]

Rip it out (or abandon in place) and install a new feeder.

I'd tell them to stop using it and shut the breaker off. Running an extension cord for the time being would be safer

I know its a problem, im interested more so on "how the heck its working this way" and why any electrician would've even considered leaving it working this way.

 

[mike93lx]

I know its a problem, im interested more so on "how the heck its working this way" and why any electrician would've even considered leaving it working this way.

There are lots of hacks in all professions.

 

[MVWSR]

Again i guess I was really hoping on the theory and principle of this . I know its not right, unsafe.

 

[mike93lx]

Again i guess I was really hoping on the theory and principle of this . I know its not right, unsafe.

You have a hot wire and something carrying current back. Looks like you found what is carrying it back.

 

[wyliesdiesels]

Wow a lot to unpack here.... I'll do my best to go over it all but pics of all panels in question with covers on and removed would be really helpful here.

So im trying to help my GrandMother & Mom with a subpanel(b) issue in a detached garage. They mentioned the golf cart stopped charging after sometime recently but cant pinpoint exactly when. Everything is 110 in this garage. And all the lights work.
Im thinking it is a result of recently done construction/electrical work, somehow damaged or dropped the neutral.

So what i know is the house had its subpanel(a) moved. Flipping from previously, inside the half bath, to the otherside of the wall moving it into the garage. (attached garage)

The location of the 2pole breaker previously tagged "shop" has been made to feed the new air handler in the attached garage. trying find the new source for the detached shop I found a single #2 spliced outside the panel to a #10 going into an open KO. This is a single pole 20.

The subpanel (b) at the detached garage has #2 mhf in conduit ,LB , with 1 leg isolated(not connected) and #6 EGC from a ground rod just outside. I can see the detached subpanel(b) is floating neutral with the neutrals & grounds bonded in the same buss. Im measuring full current on ground conductor 1.7A with lights, trying to spin up the grinder, i found the clamp at the ground rod arc'n & spark'n. I couldn't get to it with the flathead to tighten, so I changed it out. No fix.

(I assume you meant detached garage above when you said detached shop in red above)

what you described as a floating neutral is most definitely not a floating neutral since it is bonded to the ground bus. It definitely sounds like you lost the neutral connection to the house subpanel somewhere so the neutral return current is now flowing on the EGC in the MHF (if it is hooked up; you mentioned ground conductor but didnt specify if this is the EGC in the feeder or GEC going to rod) and the GEC going to the ground rod that you saw sparking.

If the neutral was isolated and lost, none of the 120v circuits in the detached garage would be working as there would be no alternate pathway (neutral bus with no connections to EGCs or GECs) for current to flow on.

The charger works from another outlet at the attached garage. I also found when trying to use a bench grinder, the lights started brownout. So as it is ,low current LED's and other 110 devices work, but the high current loads expose the problem this subpanel circuit cant handle the load.

the brown out is because the alternate pathway the neutral return current is taking back to the subpanel is not stable and is causing voltage drop.

To summarize, main has 100a 2pole going to the attached garage subpanel, feeding detached garage subpanel with a single conductor. Both subpanels the neutrals, grounds are improper bonded.

both subpanels need to have the neutral busses corrected. this may mean running 4-wire on the attached garage subpanel

The last subpanel in the detached garage has just single leg, no neutral that i can find feeding it. How tf? I mean i think I know how its working (kinda) but how to? Lol

awww ok so there is no neutral from the feeder connected to it. Is the EGC from the MHF connected? If not, then all the neutral return current is flowing on the GEC to the ground rod and thru the earth back to the main service panel in the house.
What with the absolute mess you described with the MHF spliced to #10 and going thru a KO, missing leg, etc., this all needs to be ripped out and redone especially considering its a safety hazard now with potential for shock

The neutral busses needs to be isolated/floated. The EGC and GEC needs to be connected to a separate ground bar which probably needs to be added.

The golf cart charger not working sounds like a separate issue

now earlier you stated you think its a comprised/lost neutral. doesnt sound like thats the case since there isnt one connected in the detached garage. sounds like someone started a job they couldnt finish. who wired all this? If they were paid i would make them come back and finish the job

This needs to be corrected ASAP as its a shock potential that can be fatal. If it cant be corrected properly because of money, then disconnect the detached garage so someone doesnt get hurt.

 

[wyliesdiesels]

You have a hot wire and something carrying current back. Looks like you found what is carrying it back.

sounds like the ground rod (and possibly the EGC in the feeder) is carrying the neutral return current since there is no neutral wire connected anywhere. CRAZY!

 

[TRWham]

sounds like the ground rod (and possibly the EGC in the feeder) is carrying the neutral return current since there is no neutral wire connected anywhere. CRAZY!

A homemade Single Wire Earth Return (SWER) system with assistance from the EGC. The current will flow through both the earth and EGC in proportion to their impedance and potential difference so I would guess most is in the EGC. I have seen it happen strictly via earth when the neutral to a structure was damaged and the current still wanted to go home one way or another.

 

[mike93lx]

I wonder if you can get more current to flow after a nice rain

 

[dave*99]

You should be able to collect worms in the yard along wherever that current is going,.

 

[MVWSR]

I think you fully understand, and nailed it. When I get off the road in a few hours, ill re-read and try to answer the missing blanks

- at SP(b) no EGC in the MHF, just 2 hots & neutral .that neutral bonded to GEC & rod, along with all branch neutrals & ends

- based on the trench of the new gas line to the new tankless water heater, its likely they comprised the MHF feeder to SP(b). 95% of the time its just LED shop lights giving the appearance we are left with of nothing happened .

Besides the work in the past 9months, the no EGC with MHF, and all gnd/neu bonded in SP(b) have been that way for 50years.

 

[dave*99]

In addition to the hazard to people, the dogs, animals etc. are also at risk. If they step in a hot spot in the yard

 

[JohnX14]

I agree - shut off power to this garage until it's repaired properly. A lot of potential (no pun intended) for someone to get hurt with this setup.

 

[sparky 1971]

That's an effed up mess, but I doubt the guys that were there knew anything about it. If anything, they probably walked in the garage, checked the lights, and with a little three light tester, verified all the receptacles were working. They may not have even done that.

I've seen it once and heard about many others where the farmers use a similar trick. They'll have about 1000' of wire that is so old it's no longer insulated running about 7' off the ground to a well. They need an electric fence so they tap into a hot wire using a hose clamp and pound a piece of scrap pipe or a broken fence post in the ground for a neutral: alas they have oneten from twotwenny. The one I saw, he wanted me to install a weatherproof box and cover so it would be more permanent than a receptacle hanging in the air. When I asked if he wanted to take care of the 1/4 mile long trench or wanted me to hire someone, I was asked to leave and never come back. I have honored that request.

 

[BurtEggley]

First thing I might do is find out who did the work, and then check the state license board to see if they are licensed. If yes then I would get them back out to fix what they broke or did wrong. If they are not licensed then find someone who is. Electricity is not going to say sorry if it hits you, or someone else, nor is it going to ask you not to do something stupid you might be about to do. I have been doing my own electrical work for 60+ years, was thoroughly trained in electronic engineering, but these days the codes can change so fast that it is just easier to hire an electrician friend to do anything I have questions about. I would not even think about moving a panel in an old home myself. The guy next door tried it using a handyman three months ago, and it was just completed 2 weeks ago because the city and POCO inspectors found so many violations, and had to come back over and over.