# Help! Glowing spot at bonding screw



## WillK (Aug 29, 2010)

So I heard a faint sound that could have been either a sizzle or a squirrel on the roof. Since a quiet house with a 5 year old girl, a 6 year old boy and a high strung redheaded wife is something that only happens when everyone is asleep, I decided the best way to figure out if it was electrical was to take off the cover from my main panel.

Sure enough, I saw a little spot glowing on the side of my bonding screw. By the time I took the picture, the spot had cooled down to the point it isn't glowing enough to capture in a photo. However the label next to the spot is burnt and the neutral wire for the dryer shows signs of having overheated.

I have 2 questions:

One thing that seems to be needed is to ensure the bonding screw is tightenned properly, is there any reason to be concerned about doing this (I'd otherwise assume the answer is no, but with enough current to cause metal to glow where there should be no current flow, I don't want to assume it's safe.)

Second question: What could cause this? 

For those that don't remember, I installed this panel myself and it was done under permit with very close scrutiny under inspection. All the circuits in this panel are new, my POCO moved the service entrance to this panel just before labor day after which a tree fell on the service entrance.

For some reason I'm having difficulty posting pics, but it's a 200A Homeline panel and I'll get back to post pics later when I Can.


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## WillK (Aug 29, 2010)

I have the photos attached now.

The bonding screw was originally green.

I've tightenned the bonding screw a quarter turn but it's still acting the same. I'm pretty sure I probably originally went so far as putting a torque wrench on the screw.

Also I've shut off the breaker for the garage and dryer, but that had no effect.

Could I be getting current jumping from one of the hot wires to the neutral in the service entrance? After the tree fell, I had complained about how the POCO fixed it, but they said it was fine. Their fix put the hot wires under tension.


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## gregzoll (Dec 25, 2006)

Power surge most likely, somewhere on the same leg that your house is on.


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## brric (Mar 5, 2010)

Where is the grounding electrode conductor??????????
And what type of electrode(s) do you have?


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## Stubbie (Jan 7, 2007)

When you say you turned off the dryer breaker and garage breaker and it didn't change anything are you saying that the bonding screw is continuing to glow ?


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## WillK (Aug 29, 2010)

The panel has a GEC connected to the ground bar on the right hand side and it connects to two 5/8" ground rods.

It does not glow continuously. It is arcing intermitently. It stopped for a little while when I asked my neighbor if he'd stop by and look at it, but it has since restarted.


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## WillK (Aug 29, 2010)

Stubbie said:


> When you say you turned off the dryer breaker and garage breaker and it didn't change anything are you saying that the bonding screw is continuing to glow ?


Yes. The arcing it was doing intermitently did not seem to stop when I did anything like shutting off the garage and/or dryer circuit breaker, and it did not change either with shutting off bathroom lights, christmas tree or anything else I tried.

I had been noticing that the bathroom lights would dim for a second here and there in the morning, but I never noticed anything else. Today now that I noticed the ground bonding screw, I'm noticing that when it arcs that a slight dimming of any incandescent lights in the house can be seen.


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## AllanJ (Nov 24, 2007)

Flip off all branch circuit breakers. Then turn on breakers one at a time or a few at a time. Can you isolate the glowing spot to just one breaker? What appliances does that breaker serve?

Next, unplug everything except for a few incandescent lights. Remove the bonding screw. Turn on the breakers for the incandescent lights. Go upstairs and turn individual lights on and off. Do other lights dim or brighten? Try plugging in the incandescent light into different circuits.

With the bonding screw removed and a few incandescent lights turned on, and all 240 volt circuits (double breakers) flipped off what is the voltage from hot to hot, and from hot to neutral and from neutral to ground in the panel. Write it all down.

By the way, hot shorting to neutral up on the line going to the utility pole will probably not cause the glowing spot you described.


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## kbsparky (Sep 11, 2008)

It sounds like you have quite a load imposed on the connection between the grounded enclosure of your panel, and the neutral wires.

I see from your photo that you have a separate equipment grounding bar present. You may have back-feeding juice coming in from your water mains, if you are bonded to a municipal water system.

OR your neutral line outside could be bad, and all your juice is returning VIA your water pipes. Either way, you should call the power company.

Is this a sub-panel, or your main service panel (It should be your main service panel, considering there is a bonding screw present)?


Since you have separate equipment grounding bars, AND you are dealing with the main service panel, start by installing a jumper wire between them. That should eliminate the potential between the neutral and the enclosure.


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## joed (Mar 13, 2005)

kbsparky said:


> It sounds like you have quite a load imposed on the connection between the grounded enclosure of your panel, and the neutral wires.
> 
> I see from your photo that you have a separate equipment grounding bar present. You may have back-feeding juice coming in from your water mains, if you are bonded to a municipal water system.
> 
> ...



Since there should never normally be any current flow through the bond, this is the best advice you have received. Loose neutral connection on your or a neighbour's service was my first thought.


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## WillK (Aug 29, 2010)

kbsparky said:


> Is this a sub-panel, or your main service panel (It should be your main service panel, considering there is a bonding screw present)?
> 
> 
> Since you have separate equipment grounding bars, AND you are dealing with the main service panel, start by installing a jumper wire between them. That should eliminate the potential between the neutral and the enclosure.


The arcing at the bonding screw is observed in the main service panel. I originally installed this as a sub with the intent of moving the service entrance such that this panel became the main. Late August is when the POCO completed the move of the service entrance.

My longer term intent is to move all the old circuits from the original main panel, which is now acting as a subpanel. The old work is suspect, but the worst has been replaced.

At any rate, after the PoCo connected, a tree fell on the service entrance. We didn't lose power. The Poco disconnected and reconnected over top of the fallen tree. But the service drop hung too low to the garage, so I called and they came out and pulled it tighter to gain clearance, and reconnected. Then after that I had an electrician replace a broken insulator in the service cap, so that would be a third time the service connection at the top of the service mast was redone.

At any rate, I'll try shutting off more breakers after kids go to bed. I've been meaning to disconnect the old main which is now a sub since that would isolate a big chunk, but the TV and first floor lights run off that and the kids would start shrieking without TV or lights.


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## WillK (Aug 29, 2010)

joed said:


> Since there should never normally be any current flow through the bond, this is the best advice you have received. Loose neutral connection on your or a neighbour's service was my first thought.


And the same electrician that replaced my service cap insulator replaced my neighbor's main panel, about the same time the other half of my tree would've landed on his service entrance (actually it fell while they had it down.)


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## WillK (Aug 29, 2010)

One note I wanted to add: Same time we got the service move, PoCo upgraded the neighborhood including us to digital meters. I was wondering how well this might serve in the PoCo being able to detect a problem remotely if I was to call?


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## gregzoll (Dec 25, 2006)

Not really. They operate in the same sense that a Ted5000 does, but only update in a lesser rate than the Ted does.


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## Billy_Bob (Sep 11, 2008)

If an appliance (such as the dryer) were to have a hot shorting to ground, how would that hot current get back to neutral?

Only via that bonding screw?

Do you have 2 ground bars?

Do they both connect to ground via heavy gauge ground wires? Or is one only connected to your ground and to neutral via that screw?


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## ddawg16 (Aug 15, 2011)

Take a voltmeter and measure between neut and your two hots.....maybe turn something on like the dryer to see if there is a voltage change. Both of your hots should be within a couple of volts with the other....but if one leg jumps up in voltage and the other drops down....you have a problem with the transformer....

That one neut that is getting hot....do you know where it is going?


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## WillK (Aug 29, 2010)

The screw bonds neutral to the chassis and both grounding bars are attached to the chassis.

I've done some more diagnostics:
With the main breaker off, the arcing stops.
With all circuits off and the main breaker on the arcing stops.
With everything off except the old main which is now a subpanel, arcing occurs.
With a few other things on, but the old main which is now a subpanel off, arcing occurs.

It seems that I get the arcing when any power is on, with no particular connection to any circuit.

I also made another attempt to tighten the bonding screw, it is now welded.

I know the info above is probably more useful diagnostic-wise than a video, but I have one which I'll be putting on youtube and posting a link shortly.


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## WillK (Aug 29, 2010)

ddawg16 said:


> Take a voltmeter and measure between neut and your two hots.....maybe turn something on like the dryer to see if there is a voltage change. Both of your hots should be within a couple of volts with the other....but if one leg jumps up in voltage and the other drops down....you have a problem with the transformer....
> 
> That one neut that is getting hot....do you know where it is going?


The neutral that appears to be getting hot goes to the dryer. I think it's more likely it's getting hot due to proximity to the arcing, if the wire was heating up then the burn would not be isolated to the area near the neutral bar.

Before the kids went to bed I put the cover back on. When I ran my latest diagnostics, the cover was warm over where the arcing occurs.

And I haven't gotten out a voltmeter yet because it'll take some searching in the garage. Kids are asleep now so I will have time for that next.


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## ddawg16 (Aug 15, 2011)

We need voltage readings....but it really sounds like your return path is via earth ground and not your neutral....


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## Billy_Bob (Sep 11, 2008)

Sounds to me like something is shorting to ground in the old panel (subpanel).

Or an appliance or circuit connected to that panel.

(Hot shorting to ground.)


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## Jim Port (Sep 21, 2007)

Is the bond screw still installed in the old panel?


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## joed (Mar 13, 2005)

If it was a short to ground the breaker would be tripping. 
It sounds to me like an open neutral causing the current to flow on the ground wire(from the panel not from a circuit) instead of the neutral.
Do you have a clamp on ammeter? Can you measure the current on the main service neutral and the main service ground wire. Try the main water line as well.


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## WillK (Aug 29, 2010)

Jim Port said:


> Is the bond screw still installed in the old panel?


I have removed the bond screw in the old panel.


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## Stubbie (Jan 7, 2007)

Reason I asked earlier was to clarify that the event is still occurring. Kb sparky is likely correct in his analysis. The only word of caution I'd like to convey is that your enclosure metal and ground wires are likely energized. From what source is yet to be determined. Becareful with this .. it may be more dangerous than you might think.

The discolored insulation on the dryer neutral at its connection point to the neutral buss bar lends itself to a high resistance return. As Joe said an amp meter would be your best friend at this point IMO ...


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## WillK (Aug 29, 2010)

joed said:


> If it was a short to ground the breaker would be tripping.
> It sounds to me like an open neutral causing the current to flow on the ground wire(from the panel not from a circuit) instead of the neutral.
> Do you have a clamp on ammeter? Can you measure the current on the main service neutral and the main service ground wire. Try the main water line as well.


I don't have a clamp on ammeter.

Did I mention the bond screw is now welded, and the arcing is continuous at this point?


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## Billy_Bob (Sep 11, 2008)

The breaker might not trip if it was a high amperage breaker (such as the breaker to the old panel). That screw might just appear as a normal load to that breaker. A heating element!


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## brric (Mar 5, 2010)

WillK said:


> I don't have a clamp on ammeter.
> 
> Did I mention the bond screw is now welded, and the arcing is continuous at this point?


At this point it seems to me you need a professional on site ASAP or sooner.


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## WillK (Aug 29, 2010)

I've got my electrician coming out tommorrow afternoon, I spoke with him on the phone just now and that's about the sense of urgency he assigned to it when I described it as I had above. He also indicated that if they found it was with the PoCo he had contacts to break through the red tape and maybe get things to happen a little quicker.

Here's the video now:
http://www.youtube.com/watch?v=TUz7wbOMYik

Since the last work that was done, the meter was never re-sealed so I'm thinking maybe next I'll open it up and see if there's anything visually obvious. When I go to bed, though, I'm shutting everything down that I can... I'll have to leave things on like the kids lights, alarm clock, fridge, sump pump, fire alarms. Definitely shutting off electronics once I'm done talking to you guys... This laptop is going on battery.


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## WillK (Aug 29, 2010)

Pics of the meter socket top and bottom from just now, from my layman's perspective it doesn't look like a smoking gun. I'm thinking I'll go through the exercise of calling this in to the PoCo now as well. The arcing is very unsettling.

I'll also see if I can shut off the main breaker and get a jumper in between ground and neural bars using light from the laptop to work. At least maybe I can eliminate the arcing.


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## jimmy21 (Jul 2, 2008)

I think that screw is what bonds the neutral bar to the neutral service conductor and its making a crap connection causing it to heat up. Take that screw out and wire brush it, apply some de-ox and torque it back down.

Nevermind. Looks like that screw bonds the can. There shouldn't be any current on it, but either way, the heat is from a poor connection


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## WillK (Aug 29, 2010)

jimmy21 said:


> I think that screw is what bonds the neutral bar to the neutral service conductor and its making a crap connection causing it to heat up. Take that screw out and wire brush it, apply some de-ox and torque it back down.


Too late, it's welded in.

For other matters, I found 2 voltmeters fairly easily, but the digital meter I didn't find the leads. I have an older analog meter that has the leads, so in the dark it's hard to get a precise reading, but here's what I found.

I measured hot-to-hot and got 240 volts.
I measured hot #1 to neutral and got 140 volts
I measured hot #2 to neutral and got 110 volts

I got the same readings with some circuits on so I could see as I got with all circuits off.

Again, these aren't highly precise readings, but there's clearly a difference in voltages at the hots whether load is present or not.


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## Jim Port (Sep 21, 2007)

jimmy21 said:


> I think that screw is what bonds the neutral bar to the neutral service conductor and its making a crap connection causing it to heat up. Take that screw out and wire brush it, apply some de-ox and torque it back down.
> 
> Nevermind. Looks like that screw bonds the can. There shouldn't be any current on it, but either way, the heat is from a poor connection


Correct, the screw bonds the enclosure to the neutral. The neutral connection should be made on the buss to the neutral conductor.


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## insaneirish (Jul 29, 2011)

WillK said:


> Again, these aren't highly precise readings, but there's clearly a difference in voltages at the hots whether load is present or not.


You're getting a voltage divider effect from different loads on each leg and a bad return path. I would just call the PoCo right now, and tell them your electrician diagnosed a floating neutral.

If he still comes tomorrow and says the same thing, you've gained some time (only maybe since it's a Sunday night). If he finds something else, no harm done.

The circumstantial issues with things happening after the storm further the case for a floating neutral.

Personally, I would power down the house completely (this might bolster your case with the PoCo). The arcing is very concerning.


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## Jim Port (Sep 21, 2007)

WillK said:


> Too late, it's welded in.
> 
> For other matters, I found 2 voltmeters fairly easily, but the digital meter I didn't find the leads. I have an older analog meter that has the leads, so in the dark it's hard to get a precise reading, but here's what I found.
> 
> ...


The voltage difference between the leg is signs of a loose neutral.


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## WillK (Aug 29, 2010)

I went to my neighbor's house and checked, and his voltages were the same on both legs, but I wasn't going to power down his house.

I borrowed a flashlight (we gave up on flashlights because every time we have one, the kids find them and use up the batteries or otherwise destroy them) and this time I found that with the main shut off that both legs are measuring 120-125.

I installed a jumper from the LH ground bar to the neutral bar (#4 solid copper) and now both legs read 120-125 and the arcing stopped.

So I won't cancel any appointments, it sounds like something still isn't quite right. At least I can feel safer leaving the alarm clock on, but I'll be up a bit longer so if anyone feels different I'd like to hear.


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## jimmy21 (Jul 2, 2008)

WillK said:


> I went to my neighbor's house and checked, and his voltages were the same on both legs, but I wasn't going to power down his house.
> 
> I borrowed a flashlight (we gave up on flashlights because every time we have one, the kids find them and use up the batteries or otherwise destroy them) and this time I found that with the main shut off that both legs are measuring 120-125.
> 
> ...


I think that neutral bar wasn't making a connection and the neutral current on that buss bar was trying to go through the enclosure. Or perhaps there was supposed to be a jumper from the original installation and it wasn't installed. 

You should probably bond your enclosure with a new lug or something, since the factory one is now useless


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## kbsparky (Sep 11, 2008)

WillK said:


> ...I installed a jumper from the LH ground bar to the neutral bar (#4 solid copper) and now both legs read 120-125 and the arcing stopped.....


Yup, that's the short-term fix for the moment. At least, your box won't do a melt-down overnight.

Since this is your main service panel, I'd leave that in place in lieu of the bonding screw, which is toast at this point. #4 is the proper size for a 200 Amp service.

When your electrician shows up tomorrow, he should be able to figure out why your neutral has failed. It could be a bad or broken connection outside, as a result of the recent tree incidents. Or some other bad connection on the pole or transformer.


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## kbsparky (Sep 11, 2008)

Stubbie said:


> Reason I asked earlier was to clarify that the event is still occurring. Kb sparky is likely correct in his analysis.....


Thanks for the compliment. Hey welcome back! Have not seen you around here for MONTHS!

How have you been?


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## Speedy Petey (Feb 1, 2004)

Jim Port said:


> The voltage difference between the leg is signs of a loose neutral.


Yup. All signs so far point to this. The up and down (L-N) voltage readings confirm it.


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## frenchelectrican (Apr 12, 2006)

Wilk.,

I am not sure if I did catch someone mention the bonding on the water line but if that the case if you are on the métro { city } waterline then there is one more step you will have to do this but senice you will have your electrician to come out and assit you on the loose netural connection situatuion.

For the water pipe bonding what I useally do is take a ampclamp and read the current drawage { there is a serious warning JAMAIS (NEVER) remove or loosen the bonding clamp for safety reason }

Some case with bad netural connection you will get current reading thru the water pipe { only if you have metal water pipe run underground that will useally do this but plastique it will do squat } 

By the way do you have electrique water heater ?? if so it may have bad heating element going out. ( this generally pretty common on hard water situation ) 

Few guys in this fourm did give you the best answer there.

Merci,
Marc


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## WillK (Aug 29, 2010)

Thanks to all.

Regarding the water heater and water pipes, that was a point I had adressed to satisfy concerns raised by the inspector on the permit... I had assumed that it was bonded, but apparently I needed to redo it plus the code when it was bonded previously only needed it to be bonded one place. So I have a single wire clamped to the water pipe at both sides of the meter then both sides of the water heater and then to the gas pipe.

The meter isn't metal. The water heater is gas. The pipe coming from the city water main is copper. The house is plumbed mostly with copper, except an icemaker line I did in CPVC.


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## Stubbie (Jan 7, 2007)

kbsparky said:


> Yup, that's the short-term fix for the moment. At least, your box won't do a melt-down overnight.
> 
> Since this is your main service panel, I'd leave that in place in lieu of the bonding screw, which is toast at this point. #4 is the proper size for a 200 Amp service.
> 
> When your electrician shows up tomorrow, he should be able to figure out why your neutral has failed. It could be a bad or broken connection outside, as a result of the recent tree incidents. Or some other bad connection on the pole or transformer.


I'm betting the service neutral has degraded from broken stranding. The only thing I have seen similar to this was a situation years ago where a home lost one leg of the service. That turned out to be a broken and corroded connection at the drip loop from a split bolt connection. The next door neighbor said she had brightening lights and dimmings lights all the time. I took a look see and the bonding screw it was bright red as was the neutral bus for about an inch. I followed the triplex out to the pole and could tell that several of the strands were broken on the service neutral (messenger) and only one or two remained intact just before the center tap of the transformer. POCO sent a bucket truck and repaired it a few hours later. I've never seen the arcing before though and I was starting to think that the bond screw in this example was not tight and the current using it was jumping the air gap between the screw head and the neutral bar.

To answer your other question ... I've been fine and life is good. Thought I would check in and see how all you guys have been doing these past months.


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## AllanJ (Nov 24, 2007)

Running a jumper from the neutral bar to the panel metal itself is a suitable permanent substitute for the ground screw that digs into the panel back and which, here, is welded in a position that does not make good contact. Main breaker off when doing this.

When it keeps arcing from continuous power usage it can get mighty hot, enough to make nearby metal strips red hot. The panel back, being a larger piece of metal, might not get quite as hot but still hot enough to burn your fingers.

If you keep load to a minimum (possibly leaving the refrigerator plugged in but definitely not using stove or oven or dryer) you might get by with a bad neutral and with the ground acting as neutral for a short time until the power company can come out and fix it.


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## AllanJ (Nov 24, 2007)

Running a jumper from the neutral bar to the panel metal itself is a suitable permanent substitute for the ground screw that digs into the panel back and which, here, is welded in a position that does not make good contact.

If you keep load to a minimum (possibly leaving the refrigerator plugged in but definitely turning off electric water heater and not using stove or oven or dryer incl. hair dryer) you might get by with a bad neutral and with the ground acting as neutral for a short time until the power company can come out and fix it.


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## carmusic (Oct 11, 2011)

you can just move the neutral wire on the right neutral bus and put it at the left one and completely remove right neutral bus as it is defective now. This has nothing to do with ground, it was just a loose bus connection


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## WillK (Aug 29, 2010)

carmusic said:


> you can just move the neutral wire on the right neutral bus and put it at the left one and completely remove right neutral bus as it is defective now. This has nothing to do with ground, it was just a loose bus connection


If you mean moving all the wires on the RH neutral bus to the LH neutral bus, part of the problem with that is I don't think the AFCI neutral pigtails would reach.

If you're talking about the #2 wire attaching to the neutral bus, that's the neutral for a subpanel. The incoming netural is in the center between the two hots. I've added descriptions to my earlier diagram.


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## WillK (Aug 29, 2010)

AllanJ said:


> Running a jumper from the neutral bar to the panel metal itself is a suitable permanent substitute for the ground screw that digs into the panel back and which, here, is welded in a position that does not make good contact. Main breaker off when doing this.
> 
> When it keeps arcing from continuous power usage it can get mighty hot, enough to make nearby metal strips red hot. The panel back, being a larger piece of metal, might not get quite as hot but still hot enough to burn your fingers.
> 
> If you keep load to a minimum (possibly leaving the refrigerator plugged in but definitely not using stove or oven or dryer) you might get by with a bad neutral and with the ground acting as neutral for a short time until the power company can come out and fix it.


Yeah, I suspect the insulator behind the bus might've slightly melted. I can see bubling on the surface of the bus. The bus bar did not get to the point that it was glowing.


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## WillK (Aug 29, 2010)

Stubbie said:


> I've never seen the arcing before though and I was starting to think that the bond screw in this example was not tight and the current using it was jumping the air gap between the screw head and the neutral bar.


I think that the arcing was most likely jumping an air gap between the screw head and the neutral bar. By the time I saw what was going on, I suspect the neutral bar had heated to the point the plastic behind had melted some allowing it to lose compression. When I found I was able to tighten, I probably bent the neutral bar back further, which bent it such that it moved further away from the screw head on one side.


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## mpoulton (Jul 23, 2009)

I bet you've deduced this already, but your home's service neutral current is returning on your water line, through the water pipe bonding connection. So don't remove that! If you do, the grounding system (including the clamp and bare wire you just removed and are still holding) will be electrified. Using any 240V loads should be fine and have no influence on this, but you should keep 120V loads to a minimum, and preferably well balanced. Fixing an open neutral is a power company emergency - they should fix it within a few hours at most.


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## brric (Mar 5, 2010)

Part of the problem is that the grounding electrode conductor should be terminated on the neutral buss, not on the auxillary ground bar attached to the can.


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## WillK (Aug 29, 2010)

FWIW it's now confirmed by an electrician, I have no connection to neutral and the break is in the Poco's service drop.


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## kbsparky (Sep 11, 2008)

You should be able to get reimbursed by the POCO for the electrician's bill for this problem.

Submit it to them since it was THEIR wire that was the culprit.


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## WillK (Aug 29, 2010)

brric said:


> Part of the problem is that the grounding electrode conductor should be terminated on the neutral buss, not on the auxillary ground bar attached to the can.


I'll admit I by no means would claim to know better because I don't, but it was connected as is when the AHJ inspected, and anyone who recalls all the posts I made at the time can attest that he really made me fix a lot of things, so I would be under the impression that if it was a code violation he would have directed me to change it.

With that said, there are particular reasons why I did not connect it as you say. This panel was first installed as a sub-panel, knowing it would later be the main panel. As such, it needed to have ground and neutral seperated until the day that the PoCo moved the service entrance to the new service riser, meter socket, etc. that is behind this panel.


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## brric (Mar 5, 2010)

WillK said:


> I'll admit I by no means would claim to know better because I don't, but it was connected as is when the AHJ inspected, and anyone who recalls all the posts I made at the time can attest that he really made me fix a lot of things, so I would be under the impression that if it was a code violation he would have directed me to change it.
> 
> With that said, there are particular reasons why I did not connect it as you say. This panel was first installed as a sub-panel, knowing it would later be the main panel. As such, it needed to have ground and neutral seperated until the day that the PoCo moved the service entrance to the new service riser, meter socket, etc. that is behind this panel.


The objectionable current is going through the bonding screw, through the can to the grounding electrode conductor. Had the GEC been terminated on the neutral buss, current would flow through the buss to the GEC rather than through the bonding screw and can.


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## WillK (Aug 29, 2010)

brric said:


> The objectionable current is going through the bonding screw, through the can to the grounding electrode conductor. Had the GEC been terminated on the neutral buss, current would flow through the buss to the GEC rather than through the bonding screw and can.


Yes, but the return path to the transformer should be through the neutral not the GEC, and the real problem is that the neutral is broken and the system is using the GEC as the return path to the transformer - i.e. this is likely causing the water pipes to be energized.


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## brric (Mar 5, 2010)

WillK said:


> Yes, but the return path to the transformer should be through the neutral not the GEC, and the real problem is that the neutral is broken and the system is using the GEC as the return path to the transformer - i.e. this is likely causing the water pipes to be energized.


 That is totally correct. However, the arching may not have occured.


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## biggles (Jan 1, 2008)

that's not a neutral from the pole..just a mechanical ground...see that black/white striped on the left catching all those whites...the mounting screw is taking the hit when the dryer runs as the return to the panel....need to take that dryer over to that left neutral bar or bring the neutral over to the grounding bar to give it an easier path when running...if you slip that white/burnt insulation wire out with the dryer running it would shut off...


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## bernie963 (Dec 18, 2010)

has poco been there yet to find and fix the bad neutral? this is more important than the rest of the discussion. After it is fixed, then the discussion. I worked for 11 years doing cust service for an electric utility. a large number of trouble calls were open neutrals. they were high priority right behind downed wires, etc.


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## WillK (Aug 29, 2010)

biggles said:


> that's not a neutral from the pole..just a mechanical ground...see that black/white striped on the left catching all those whites...the mounting screw is taking the hit when the dryer runs as the return to the panel....need to take that dryer over to that left neutral bar or bring the neutral over to the grounding bar to give it an easier path when running...if you slip that white/burnt insulation wire out with the dryer running it would shut off...


You say that as if you've never seen SE-U cable, a Homeline panel, and you know that a wire I label as the neutral (from an SE-R cable that is #2 AWG and would be undersized for 200A service) is actually the neutral from the pole.

I'm quite confident I labelled my picture correctly.


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## WillK (Aug 29, 2010)

bernie963 said:


> has poco been there yet to find and fix the bad neutral? this is more important than the rest of the discussion. After it is fixed, then the discussion. I worked for 11 years doing cust service for an electric utility. a large number of trouble calls were open neutrals. they were high priority right behind downed wires, etc.


I wish you worked for my PoCo. I called while the electrician was there in hopes I'd reach someone and I could put the electrician on the phone. They said to call back tomorrow. I asked again "I have flickering lights and an electrician saying I have an open neutral from the pole, and you're telling me to call back tomorrow??" They confirmed.

I've filed a complaint with the state's utility regulatory commission.


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## bernie963 (Dec 18, 2010)

tomorrow is not acceptable. call again asap. all electic utilities have 24 hr coverage. a trouble man should be dispatched.


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## mpoulton (Jul 23, 2009)

WillK said:


> I wish you worked for my PoCo. I called while the electrician was there in hopes I'd reach someone and I could put the electrician on the phone. They said to call back tomorrow. I asked again "I have flickering lights and an electrician saying I have an open neutral from the pole, and you're telling me to call back tomorrow??" They confirmed.
> 
> I've filed a complaint with the state's utility regulatory commission.


They must have an emergency number. Call it until they respond. Tell them part of your panel is glowing red! But still follow through with the complaint to the commission. Totally unacceptable.


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## biggles (Jan 1, 2008)

your labeling the sub panel gound and neutral are the same wires:wink: all are raw grounds not load neutrals as that black/white stripe is from the pole on the left terminal strip that screw is arc'g because voltage is passing thru it. disconnect the black wire from the pair of wires that white comes from 115V... there is no wire going to that right side raw terminal bar the screw is the only thing tieing it to the panel


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## WillK (Aug 29, 2010)

With all due respect, why are you so sure of yourself that you persist with insisting you're right and I'm wrong about labelling a picture of a panel I installed myself which you seem to not have seen before in spite of how common it is?



biggles said:


> your labeling the sub panel gound and neutral are the same wires:wink: all are raw grounds not load neutrals as that black/white stripe is from the pole


No. You're wrong. The black wire with the white stripe on the left side neutral bus does NOT come from the pole, it connects to a sub-panel in the house in another room. I know this because I ran the wire myself. It is from a 2-2-2-4 SE-R cable, which means it has a 2 gage black wire, a 2 gage black wire with red stripe, a 2 gage black wire with white stripe and a bare aluminum ground conductor. This is a 200A panel. 2 gage aluminum would be undersized for 200A. It would be undersized for 100A. The subpanel is fed from a 60A breaker.

The wire I'm labelling as subpanel ground is the 4 gage aluminum wire from the SE-R cable going to the subpanel. It is not the same wire as the neutral wire from the meter socket. 

The bare wire going into the center terminal is the neutral wire which connects to the utility pole (after it goes out to the socket where it connects to the neutral wire going up the service riser to the service drop). It is part of a 4/0 SE-U cable. That is to say a black 4/0 wire, a black with red stripe 4/0 wire and a series of aluminum strands wrapped around the outside, and no ground conductor. 



> on the left terminal strip that screw is arc'g because voltage is passing thru it. disconnect the black wire from the pair of wires that white comes from 115V... there is no wire going to that right side raw terminal bar the screw is the only thing tieing it to the panel


The right hand neutral bus bar is tied to the neutral wire that connects at the top in the middle between the two 4/0 black hot wires the same way the left hand neutral bus bar connects to it. The flat metal strip to which all 3 of these items connects passes beneath the two terminals where the hot wires connect to the main breaker. That's how the neutral bars are set up on a Square-D Homeline panel, it's pretty common and I'd assume that it isn't necessary to explain that to an electrician that was sufficiently qualified to provide the advice you're offering.

As I've said, I did this work, I did it under permit, I consulted here extensively in the process, I had it inspected by a very thorough AHJ and passed. 

From left to right, there are 4 bus bars. The left most bus bar is for ground, then there is a neutral bus bar to the left of the circuit breakers, then a neutral bus bar to the right of the circuit breakers and another ground bus bar to the right of that. The right hand ground bus bar is not visible. 

Both ground bus bars are only going to ever connect to the neutral bus bars and neutral wire by way of the grounding screw or any jumper wires that get installed. This is how it is supposed to work. This is the way the panel is built because it can be used as a subpanel which requires the bonding screw to not be present. If used as a subpanel (as I said, it was) neutral and ground MUST be seperated.


Sorry if I'm coming down hard, but I tried to subtly point out before that you sound like you're wrong and you don't know what you're talking about. I would really hate to think that someone could read this and not know any better and follow your advice, hell if I didn't know any better and read what you posted and took it as truth I might end up disconnecting the service neutral myself and replacing it with the undersized neutral to the subpanel.


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## WillK (Aug 29, 2010)

mpoulton said:


> They must have an emergency number. Call it until they respond. Tell them part of your panel is glowing red! But still follow through with the complaint to the commission. Totally unacceptable.


I agree, but as much as I'd rather not name names, this is DTE Energy in the Detroit metro area. I hate maligning unions, and I know that being an electrician pretty much means you're probably in an electricians union, so I tread carefully by saying what I'm about to say: there are a lot of bad stereotypes about unions, and I've worked with union people and groups that have not been like the negative stereotypes, but around Detroit there are certainly a lot of places those stereotypes apply. Where I've dealt with electricians locally, the reputation is that the stereotypes apply with DTE as well.

The number I called is the emergency number. They said their system is down and I need to call tomorrow morning. I've had such a hard time getting action from DTE that 1) it sounds like BS and 2) it's situation normal to me.


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## WillK (Aug 29, 2010)

bernie963 said:


> has poco been there yet to find and fix the bad neutral? this is more important than the rest of the discussion. After it is fixed, then the discussion. I worked for 11 years doing cust service for an electric utility. a large number of trouble calls were open neutrals. they were high priority right behind downed wires, etc.


FWIW I put a lot of grounding upgrades in too...

The original ground rods for the old main now subpanel are still in place connected to the subpanel, I've seen 1 not sure if there is a second.
The new main panel has 2 5/8" ground rods.
There are 2 more 5/8" ground rods for the garage subpanel.
The garage subpanel has a ground conductor with the underground feeder.
The garage subpanel also has rigid metal conduit 18" underground, this forms a continuous metal path to the main subpanel in the house.
All new ground rods are wired to their respective panels with a single continuous wire which passes through a ground lug attached on the conduit.
Another ground wire bonds the plumbing at both sides of the water meter, both sides of the water heater and the gas pipe near the water heater.
The garage is much closer to the utility poles than the house, so it's likely that the path of least resistance is more likely through the garage ground rods than the water pipes.


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## Stubbie (Jan 7, 2007)

Biggles said



> your labeling the sub panel gound and neutral are the same wires:wink:


Nope his labeling is fine



> disconnect the black wire from the pair of wires that white comes from 115V... there is no wire going to that right side raw terminal bar the screw is the only thing tieing it to the panel


Why in the world would you advise someone to do that ????



> Sorry if I'm coming down hard, but I tried to subtly point out before that you sound like you're wrong and you don't know what you're talking about. I would really hate to think that someone could read this and not know any better and follow your advice, hell if I didn't know any better and read what you posted and took it as truth I might end up disconnecting the service neutral myself and replacing it with the undersized neutral to the subpanel.


Your not coming down hard your simply telling him he doesn't understand and is obviously wrong. Persistent though he is ....


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## mpoulton (Jul 23, 2009)

WillK said:


> I agree, but as much as I'd rather not name names, this is DTE Energy in the Detroit metro area. I hate maligning unions, and I know that being an electrician pretty much means you're probably in an electricians union, so I tread carefully by saying what I'm about to say: there are a lot of bad stereotypes about unions, and I've worked with union people and groups that have not been like the negative stereotypes, but around Detroit there are certainly a lot of places those stereotypes apply. Where I've dealt with electricians locally, the reputation is that the stereotypes apply with DTE as well.
> 
> The number I called is the emergency number. They said their system is down and I need to call tomorrow morning. I've had such a hard time getting action from DTE that 1) it sounds like BS and 2) it's situation normal to me.


Sounds like fun. I'd say that "Detroit" is the explanation rather than "union". Almost all power companies are union, AFAIK, and almost all would have had a service truck out in an hour! As a construction manager, I worked with both union and non-union electrical contractors. Almost all in Indiana were union, and none in Arizona were union. I saw few quality differences, but substantial cost differences and moderate differences in ease of management.


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## AllanJ (Nov 24, 2007)

This will get the power company out in a jiffy. If there is a (added later; change the "a" to "any") utility pole on your side of the street not too far from your house and there is a bare ground wire going up the pole, you run a wire across the lawn (suggest 10 gauge or all 3 wires of a Romex cable tied together at both ends. One end goes to the neutral bus in your panel, the other end is clamped to the ground wire on the pole. This acts as a neutral jumper around the broken neutral in the service drop. 

Turn off your main breaker and try it. If this cures the unbalanced neutral problem (still don't use big 120 volt loads like hair dryers except for brief testing) then this almost certainly proves that the overhead service drop neutral was the problem.


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## WillK (Aug 29, 2010)

AllanJ said:


> This will get the power company out in a jiffy. If there is a utility pole on your side of the street not too far from your house and there is a bare ground wire going up the pole, you run a wire across the lawn (suggest 10 gauge or all 3 wires of a Romex cable tied together at both ends. One end goes to the neutral bus in your panel, the other end is clamped to the ground wire on the pole. This acts as a neutral jumper around the broken neutral in the service drop.
> 
> Turn off your main breaker and try it. If this cures the unbalanced neutral problem (still don't use big 120 volt loads like hair dryers except for brief testing) then this almost certainly proves that the overhead service drop neutral was the problem.


The utility poles are located at the rear lot line in my neighborhood, and I don't have a pole that falls on my property lines. The pole my power comes from is at the far side of the next lot north of me. His yard is kind of messy, he's almost never home and he has a dog that roams his back yard. When we first moved in, we saw a rat running across the top of the fence, climbing vines and disappearing into his second floor.

The electrician verified the neutral by pulling all 3 wires at the meter socket and measuring for voltage from the hots to the neutral. I don't know if he found low volts or no volts, I didn't ask what his meter read, but he used the words "open neutral."


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## SD515 (Aug 17, 2008)

WillK said:


> I wish you worked for my PoCo. I called while the electrician was there in hopes I'd reach someone and I could put the electrician on the phone. They said to call back tomorrow. I asked again "I have flickering lights and an electrician saying I have an open neutral from the pole, and you're telling me to call back tomorrow??" They confirmed.
> 
> I've filed a complaint with the state's utility regulatory commission.


 Isn't dealing with DTE great? :no: 
Wonder if you interrupted their office party or their game of solitaire on the computer.


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## bernie963 (Dec 18, 2010)

Has poco been out yet??? what did they find?


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## Stubbie (Jan 7, 2007)

The electrician found an open service neutral.


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## WillK (Aug 29, 2010)

bernie963 said:


> Has poco been out yet??? what did they find?


I had been considering posting updates, but I was thinking along the lines of a new thread rather than bumping a thread that had rolled down a page or two. But since you asked, I'll update here:

Weds. morning I received an e-mail from DTE customer service responding to the complaint I filed with DTE. In this e-mail, it was stated that the case was sent to dispatch at 7:29 AM that day. As far as my question about reimbursement for the electrician I had paid, they stated "we do not offer compensation for obtaining service through an electrician." I responded that I felt that reimbursing me for the $85 I paid for my electrician should be the least they do, and I should probably also seek reimbursement for the damage that their faulty equipment cause to my new service panel and anything else that I may find in the future that has been damaged as a result of this.

Weds. we went to dinner for my 40th birthday. Before we left for dinner, the online system indicated that no estimate was available for the restoration. After we got home, the online system indicated the work was complete. I pulled my jumper wire, and sure enough, the bonding screw was still arcing.

I called, understandably perturbed, but I refrained from anything abusive other than a stern tone of voice. The customer service rep informed me that the issue had been referred to a tree cutting crew and a line crew, so the case was still active with another department. Indeed, the service drop is touching a tree in a neighbor's yard at 2 points. This is more a result of the service drop having been pulled towards the house before the midspan.

Yesterday, I was fortunate enough to have been home for lunch when people started showing up from DTE. First a tree crew showed up, but they also left without talking to me. Then a little while later, a DTE guy came out and we looked at the line together. He basicly confirmed what I had been saying since Labor Day: The service drop should not have been pulled so far towards the house, and replacing the service drop will get it away from the trees and correct the open neutral.

The work will be done on Monday, Dec. 12.


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## insaneirish (Jul 29, 2011)

WillK said:


> The work will be done on Monday, Dec. 12.


Completely unacceptable. I would have called the police and fire departments and let them deal with the PoCo.

Unreal.


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## kwilcox (Nov 19, 2011)

Unbelievable. I've never read anything like this before. The Detroit PoCo is a disgrace to the industry. Keep the kids out of the basement as long as your plumbing is energized....


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## jimmy21 (Jul 2, 2008)

Our power company would be out same day. No question about it


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## WillK (Aug 29, 2010)

kwilcox said:


> Unbelievable. I've never read anything like this before. The Detroit PoCo is a disgrace to the industry. Keep the kids out of the basement as long as your plumbing is energized....


Hehe... well, that's easy since we don't have a basement. The house is over a dirt crawlspace and has been standing since 1917 without a foundation.

So today, I went to work, then came home to see if I could work from home and keep an eye out to make sure the job got done right. When I got here, there were 4 trucks out in the street and the new service drop was already finished, they were just wrapping up some tree trimming.

I shut off my main and pulled my jumper wire to verify that the open neutral had been cured, and it had. So I put the jumper back to keep everything safe, looked outside to make sure I had proper garage clearance and that was good.

So ultimately, it seems I finally got the right people out to make the PoCo's part of the system right.


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## darlingm (Aug 20, 2011)

Been following your situation. Glad DTE finally got it sorted out. I see from your experience and other's comments that DTE is as bad as my experience with them.

They let a 50,000 volt line keep my back yard on fire for 72 hours this summer, no exxagerating. (I'm not sure I have the exact voltage correct, but the order of magnitude is correct. It was a subdivision primary transmission line. And they knew this.)

You might remember a horrendous storm in early July this year. One of my neighbor's trees came down, snapping one of the primary transmission lines that runs along our back yard. I never got them to tell me precisely how much voltage it runs, but they confirmed it was tens of thousands of volts, and researching online it looks like those are usually 50kV. One end fell into our back yard, dangling on the fence, trees, and shrubbery. We were going outside to check the house for storm damage, and I heard that horrible electrical arcing sound.

DTE's emergency line was only accepting automated calls, so called 911. Within a few minutes, the arcing quickly set the shrubbery on fire, despite everything being soaking wet from all the rain.

The fire department came out, and an hour later said their dispatcher was still on hold trying to get in touch with a person at DTE, about my fire and two others in Westland due to downed wires. Apparently DTE has an unlisted phone number for city dispatchers to be able to call - this way, the city dispatcher can sit on hold for a longggg time to speak to someone, but it at least doesn't say they're only accepting automated calls and hang up on the person. They gave me this number, and said I could try calling them too.

I'm a squeeky wheel, so I was calling the DTE city emergency line every 1-2 hours, after my last conversation with them.  That night, hold times were over an hour each.  They kept saying for 72 hours they couldn't give an ETA to get the line shut off.

Each time I spoke with them, I asked for a supervisor. I explained I knew a lot of people were without power, and I wasn't asking to have my power back -- I just wanted the line turned off. I explained that my backyard was on fire. I explained that it was dangling on a metal fence, and that everyone has metal fences linked together in my neighborhood, so there was an electricution hazard even like 10-20 houses away.

No line crews showed up, but a few DTE workers who weren't line workers came by to see the fire, and verify that the situation was really bad.

DTE supervisors kept blaming it on dispatch, saying they were sending in escalated priority tickets, but that dispatch kept sending out non-line workers and ignoring the tickets.

Fire department finally left about 6 hours into the fire, saying they couldn't sit there the whole time that it burned. They of course can't use water to fight it, and said all they could do is spray foam on our house if it got significantly closer to the house. Luckily the fire never got closer than 8-10 feet.

Fire department told us to watch the fire, and call back if it got closer to the house. So, my wife and I got to take shifts watching the line for 72 hours making sure the house didn't burn down, while frantically making phone calls to supervisors at DTE begging to just have the line shut off.

All this, while DTE was busy at work in my subdivision getting the rest of the neighborhood's power back on. I'd even drive by DTE trucks, begging them to shut it off, and they all said they had to follow the tickets in order given by dispatch, while they saw smoke off in the distance. The head line crewman that eventually came by said quite a few things about DTE that I can't repeat. He was very upset about the non-important jobs they had been having him do for the past few days when this was still going on.

Here's a link to a video I shot when it had just about started. It got much worse, but I didn't shoot any additional video.

http://www.youtube.com/watch?v=WzomgvwvCcM


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## jbfan (Jul 1, 2004)

All I can say is WOW!

I glad all you had was a fire and no one got hurt!


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## mpoulton (Jul 23, 2009)

That's unbelievable! I can't imagine that a situation like that could occur in the United States. That line was almost certainly 7200V, not higher - but an incredible hazard nonetheless.


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## AllanJ (Nov 24, 2007)

A single 7200 volt primary is one line of a 12,500 volt 3 phase primary system. It is not unheard of for the primary system to be in the 30 to 50 KV range phase to phase in which case the single primary would be around 17,000 to 29,000 volts phase to ground.

If the pole top insulator for the primary suggests a pine cone rather than a mushroom then there is a good chance that the phase to ground voltage is over 15 KV.


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## darlingm (Aug 20, 2011)

Picture came out pretty bad through a window, but gets the job done. Looks to be a pinecone style to me.

Almost all of the rest of our neighborhood got power back before the line was shut off. Strangely, to me anyway not having a great understanding of the grid, they got everyone else power except for one neighbor on one side, and two neighbors on the other side, with that line in that condition.


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## bernie963 (Dec 18, 2010)

that is totally unbelievable. around here we ran 13.8 kv. 7.2 near the salt h2o. the closest thing i ever saw was an arc on a 3 ph pole in a driving rain. the trouble man could not open the switch from the ground, so he went up in the bucket w a sledge hammer. I was inside watching. it was lighting up the sky.

i think dept public utilities needs to see that video.


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## kbsparky (Sep 11, 2008)

That size insulators could possible handle up to 14,400/25,000 Volts. But probably not 50,000.

Most neighborhood distribution systems operate at 7200/12,500 Volts.


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## WillK (Aug 29, 2010)

File a complaint with the Michigan Public Service Commission, it's the state regulatory agency responsible for holding public utility companies accountable to customers.

http://www.michigan.gov/mpsc/0,1607,7-159-16368_16415---,00.html


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