Any conclusions about black wire causes?

[ejager]

Good morning Brain trust!

I did an inspection of a 2001 condo with blackened copper wires. This was in Calgary so "high-sulpher" drywall is not really suspected, though it is not ruled out.

The wires are almost 'fuzzy black' not just a simple black/grey corrosion. First noticed it in the panel, which was in a dry storage closet. In the tightest corners of the panel, the ground wires still have patches of copper. I went looking at wall outlets and saw the same problem. Water pipe is all PEX so it was no indicator.

No pool, no signs of high humidity.... any other ideas what might be a cause?

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[Dale McNutt]

Since you say condo, I am leaning toward airborne spray either from landscape or pest control. (HOA contractors)

[AHI in AR]

I think the wire is growing a fur coat since it's too cold there at times...

[Jim Katen]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

[John Kogel]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

I think that could be it. They may have had a mobility scooter with lead/acid batteries, which they charged in the hall under the panel.

[gpdewitt]

In the 3rd picture, the receptacle, is that a hot, neutral or ground? By it's location, looks like a hot or neutral, so is that black fuzz on the insulation as well, or is that way too much bare wire for a current carrying wire?

[ejager]

The 'black wire' in the third picture was the uninsulated black ground wire, they back-stabbed the hot and neutral wires. this receptacle was 15 ft from the hall closet. The receptacle in the kitchen across the condo showed similar copper corrosion.

So the US Consumer Protection remediation guidance for homes with problem drywall calls for the replacement of all:

problem drywall;

fire safety alarm devices, including smoke and carbon monoxide alarms;

electrical distribution components, including receptacles, switches and circuit breakers; and

gas service piping and fire suppression sprinkler systems

.

http://www.cpsc.gov/cpscpub/prerel/prhtml11/11176.html

Assuming this is not drywall for the time being, would these guidelines still be the recommended course of action for electrical repairs?

And why would steel gas piping and steel fire supression sprinklers systems need repalcing? - Overly cautious?

[Marc]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

How so?

The initial charging of a new lead-acid battery results in the off-gassing of hydrogen gas. Excessive discharging results in the off-gassing of oxygen.

Excessive charging/discharging or excessive charge/discharge rates can result in the need to replace lost water, but the H2SO4 never leaves the solution...unless it spills or leaks out.

This 'fuzzy black' is a mystery!

Marc

[John Kogel]

this receptacle was 15 ft from the hall closet. The receptacle in the kitchen across the condo showed similar copper corrosion.

Rereading on a fresh coffee recharge, this is more than just a localized off-gassing, as you found it in the kitchen as well.

So the US Consumer Protection remediation guidance for homes with problem drywall calls for the replacement of all:

problem drywall;

fire safety alarm devices, including smoke and carbon monoxide alarms;

electrical distribution components, including receptacles, switches and circuit breakers; and

gas service piping and fire suppression sprinkler systems

.

http://www.cpsc.gov/cpscpub/prerel/prhtml11/11176.html

Assuming this is not drywall for the time being, would these guidelines still be the recommended course of action for electrical repairs?

And why would steel gas piping and steel fire suppression sprinklers systems need replacing? - Overly cautious?

I can't speak for them, but if the drywall was the source of this corrosion, then it would appear that replacing the iron pipe is a wise precaution, especially while it is all exposed anyway. In your case, the source of the corrosion needs to be found. I would suggest a lab test of the drywall, for starters.

Yes all the electrical needs to be inspected and the damaged sections replaced. If the source is air-borne, then the unexposed wiring should be OK, but I would pass this off to a remediation company and advise my client to sit tight.

[Jim Katen]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

How so?

The initial charging of a new lead-acid battery results in the off-gassing of hydrogen gas. Excessive discharging results in the off-gassing of oxygen.

Excessive charging/discharging or excessive charge/discharge rates can result in the need to replace lost water, but the H2SO4 never leaves the solution...unless it spills or leaks out.

This 'fuzzy black' is a mystery!

Marc

Lead-acid batteries will give off hydrogen sulfide gas when charging if their plates are damaged or if their water level is low. Try it.

[Rocon]

Guys, I am not completely buying into the sulfur or off gassing. The fuzz only occurs on black wires, and it seems only the 12-14 ga. not the larger conductors. Some may say that the larger wires are not copper, however sulfur oxidizes aluminum also.

The photos I have seen of homes with the Chinese drywall, they have no visible damage to the insulation. The sulfur passes through the insulation and corrodes the wires along the length of the wires. That is why homes with Chinese drywall cannot just strip some more insulation to expose fresh wire.

Additionally in the top left of photo #2, I can see some bright or very lightly tarnished copper. If sulfur was the issue the copper would have a complete black patina, it is next to the insulation with fuzz and should be subject to the same environmental effects.

I think it might be wise to look towards the plasticizer in the insulation casing. The plasticizer might be reacting to an environmental issue or it could be something related to the particular manufacturer of that wire.

Some more questions I would ask:

• Can the wire be identified by any of the casing marks?

o If the wire can be identified research if any insulation failures are known.

• Could the wire have been exposed to chemicals before installation?

o (back of the truck)

• Could those wires be/have been conducting too much current?

[ejager]

Sorry if I confused the issue Rocon.

The fuzz occurs only on the bare copper wires, but it was so thick that I thought I might be looking at nylon covered wires.

On the exposed end of the neutral wires in the previoiusly posted photo one, we can see the black corrosion.

In the second photo, as you pointed out there is some very bright copper. This is the ground wire and where the outher sheating for the cable protected it, it was unaffected.

In the last photo there is some regular green oxidation of screws in the grounding bar, as well as black oxidation of the ground wire.

You are right that there didn't appear to be any effect on the aluminum SEC. Here is a whole panel pic...

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My clients are not interested in pursuing the why's of how this came to be, there were enough other things off-putting about the unit and building to make them search elsewhere.

I on the other hand, want to rip apart the wall, to find the brand/manufacturerer of the wire as you suggest. I want to knock on the neighbour's door and ask if I can remove the cover from their panels, and remove some switch plates in the front lobby.

Oh, and thanks to all for all the help, insight and discussion! This board is fantastic!

[John Kogel]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

How so?

Lead-acid batteries will give off hydrogen sulfide gas when charging if their plates are damaged or if their water level is low. Try it.

For what it's worth, I remember the smell coming from a car battery on quick charge. We'd remove the caps to check the water level, and the smell was .. sulphuric.

But I can't imagine that much gas drifting all the way to the kitchen.

[:-magnify There is another possibility - Meth lab. Cooked in the kitchen, stored in the utility room.

[Terence McCann]

Any source of sulfur in the air would do it.

Battery charges are famous for it.

How so?

The initial charging of a new lead-acid battery results in the off-gassing of hydrogen gas. Excessive discharging results in the off-gassing of oxygen.

Excessive charging/discharging or excessive charge/discharge rates can result in the need to replace lost water, but the H2SO4 never leaves the solution...unless it spills or leaks out.

This 'fuzzy black' is a mystery!

Marc

Lead-acid batteries will give off hydrogen sulfide gas when charging if their plates are damaged or if their water level is low. Try it.

How would you test for the presence of hydrogen sulfide gas Jim?

[Jim Katen]

How would you test for the presence of hydrogen sulfide gas Jim?

I'd just use my nose. If hydrogen sulfide is present, it has a strong smell.

However, if it had been present in the past, I'm not aware of any way to test for it other than by the damage it leaves behind.

I can easily imagine a bad battery flooding the interior of a condo with enough gas to blacken the wires throughout.

I can also imagine that other airborne contaminants could do it as well. A meth lab might well produce this kind of damage.

The single bright piece of copper might have been exposed after the contamination occured.