Ideal Wire Nuts Turning to Powder

mbrooke

Batteries Not Included
Location
United States
Occupation
*
Anyone ever notice those red Ideal wire nuts discoloring and turning into powder especially behind luminaries? I swear I can see a re-call coming for these things.

1590115328322.png
 

brantmacga

Senior Member
Location
Georgia
Occupation
Electrical contractor
Yeh, I’ve seen it. I don’t use them. When using wirenuts I use Buchanan reds and 3M tan twisters.


Sent from my iPhone using Tapatalk
 

McLintock

Senior Member
Location
USA
Occupation
Electrician
I would guess heat. What kind of lights are they?


“ shoot low boys their riding shetland ponies”
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
HID is the worst, followed by LED. In general these wire nuts seem to self biodegrade.
Besides heat, UV light doesn't play well with most plastics. Are these wire-nuts getting exposed to direct light as well as heat? LED's would be a prime source; I don't know about HID's.
 

kwired

Electron manager
Location
NE Nebraska
I've seen it with other "wire nuts" also.

I don't see any recall coming, as they were likely used above their temp rating in those cases.

With HID's you about have to use a high temp connector. Ideal has the most common one I have found other than types that are all porcelain, theirs is some sort of black plastic. Don't know what is different, they can still degrade but seem to hold up better than any other "standard wire nut".
 

GoldDigger

Moderator
Staff member
Our church has some 300W PAR 56 spotlights that use fiberglass insulated wires and ceramic wire nuts. The connecting wire also has to be high temp rated. I would not try to use regular wire nuts there! :)
 

paulengr

Senior Member
Besides heat, UV light doesn't play well with most plastics. Are these wire-nuts getting exposed to direct light as well as heat? LED's would be a prime source; I don't know about HID's.
LEDs do not put out UV. A white LED is a blue LED with a white phosphor coating (converts blue to white. A fluorescent is mostly UV again with a phosphor coating. A metal halide is a mercury vapor lamp (almost pure UV) with a halogen gas that converts UV to bluish-white. So only the fluorescents or especially metal halides eat plastic.

Guessing the wire nuts are PVC PVC plastic uses chlorine atoms to cross link the vinyl polymers. But the chlorine turns into hydrochloric acid when it breaks down which attacks the PVC and creates a self destructing chain reaction. That’s why white (natural) outdoor PVC plumbing breaks down in ten years. If you paint it, coat it, wrap it in a nylon jacket, or fill it full of something to block UV, it lasts quite a bit longer.

The fact that it is turning to powder is a big hint...that’s not overheating which causes it to peel and crack and melt. That’s clearly either chemical attack or UV.
 

kwired

Electron manager
Location
NE Nebraska
LEDs do not put out UV. A white LED is a blue LED with a white phosphor coating (converts blue to white. A fluorescent is mostly UV again with a phosphor coating. A metal halide is a mercury vapor lamp (almost pure UV) with a halogen gas that converts UV to bluish-white. So only the fluorescents or especially metal halides eat plastic.

Guessing the wire nuts are PVC PVC plastic uses chlorine atoms to cross link the vinyl polymers. But the chlorine turns into hydrochloric acid when it breaks down which attacks the PVC and creates a self destructing chain reaction. That’s why white (natural) outdoor PVC plumbing breaks down in ten years. If you paint it, coat it, wrap it in a nylon jacket, or fill it full of something to block UV, it lasts quite a bit longer.

The fact that it is turning to powder is a big hint...that’s not overheating which causes it to peel and crack and melt. That’s clearly either chemical attack or UV.
OP said "especially behind luminaires". Whatever he is experienceing is primarily because of heat. I see this often within HID luminaires, but is behind the lamp reflector where there should be no light or UV. But use the black connectors that are rated higher temp and they definitely last much longer. Guessing they are made from a different kind of plastic than most other connectors.
 

McLintock

Senior Member
Location
USA
Occupation
Electrician
T12 lights I worked on the insulation would crumble off. Seams like those old oil filled ballast built up a lot of heat, they had the rubber like wire nuts( the kind that would not come off, had to use Klein’s). Just retro fitted some T8 to LED and the insulation was almost melted on the wire.


“ shoot low boys their riding shetland ponies”
 

flashlight

Senior Member
Location
NY, NY
Never saw those do that. I guess never saw the right conditions. Have seen plenty of old insulation on conductors go to heck, mostly on hot luminaires or next to old ballasts McLintock mentioned. But the wirenuts on those were from the 50s or 60s I think, hard plastic or bakelite?
They seemed indestructable.
 

ppsh

New User
Location
CA
Occupation
Electrician
Most often ones I see crumble are Buchanan B-caps in linear fluorescent fixtures.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
OP said "especially behind luminaires". Whatever he is experienceing is primarily because of heat. I see this often within HID luminaires, but is behind the lamp reflector where there should be no light or UV. But use the black connectors that are rated higher temp and they definitely last much longer. Guessing they are made from a different kind of plastic than most other connectors.
What type of wire are you using for the field connection at the fixture? Standard wirenuts are rated at 105°C.
 

kwired

Electron manager
Location
NE Nebraska
What type of wire are you using for the field connection at the fixture? Standard wirenuts are rated at 105°C.
Been a few times I seen HID luminiares have 90C supply conductors that fails, even if luminaire is marked for 90C supply conductors. Sometimes I would even use a high temp fixture wire in a FMC whip for those luminaires when installing new based on seeing such failures.
 
Top