What do you think caused this electrical fire?

[P3dStealth]

It's surprising to me that an outlet claiming to be rated for 50A isn't able to maintain 32A continuous. How did a product like that pass validation for being a 50A product? 32A is only 64% of max load - it should be able to maintain that without any issue at all.

My guess is it was a pisspoor installation with exceptionally loose wires, causing overheating behind the outlet.

I agree with you. Most of these melted 14-50 outlets are not torqued down correctly. I have been running a cheap 14-50 outlet for 4 years charging at 32amps no problems at all. I did however torque the lugs down to specs with a torque driver. It was surprising how hard the spec calls for and most people are not going to be getting there from just feel. My outlet doesn't even get warm.

The other issue with the cheaper 14-50 outlets is they are not designed to be unplugged often. If they become loose you need to toss them. I rarely unplug mine. If you do unplug it often get a better outlet.

I have no doubt the Bryant and Hubble are better. I think what's happening is the better product allows for an amount of negligence in the installation that the cheaper products do not. Also someone that seeks these high end brands tends to already know what they are doing and torque them correctly.

 

[Supcom]

The detail picture you see is precisely as it was when I pulled it from the wall so the aluminum connector had basically burned itself through somehow. Maybe a sharp angle bent caused a weak point?

I dunno I’ll update when somebody comes by. I don’t love the aluminum at all— particularly since the original electrician couldn’t even seem to snuggled up properly to the breaker (used to trip in 2021 shortly into a charge until I figured it was because it wasn’t tight enough so I tightened it and that stopped it—was producing a lot of heat at the panel). I know there are already threads about aluminum so I don’t want to rehash that heheh.

I suggest having a (different) electrician wire your breaker directly to the EV charging equipment with copper wire. It appears that the Grizzl-e does not have a temperature sensor in the plug (very bad design) but can be wired directly to the breaker by replacing the power cable.

 

[father_of_6]

I suggest having a (different) electrician wire your breaker directly to the EV charging equipment with copper wire. It appears that the Grizzl-e does not have a temperature sensor in the plug (very bad design) but can be wired directly to the breaker by replacing the power cable.

Hardwired is always the better choice.

 

[EatsShoots]

I agree with you. Most of these melted 14-50 outlets are not torqued down correctly. I have been running a cheap 14-50 outlet for 4 years charging at 32amps no problems at all. I did however torque the lugs down to specs with a torque driver. It was surprising how hard the spec calls for and most people are not going to be getting there from just feel. My outlet doesn't even get warm.

The other issue with the cheaper 14-50 outlets is they are not designed to be unplugged often. If they become loose you need to toss them. I rarely unplug mine. If you do unplug it often get a better outlet.

I have no doubt the Bryant and Hubble are better. I think what's happening is the better product allows for an amount of negligence in the installation that the cheaper products do not. Also someone that seeks these high end brands tends to already know what they are doing and torque them correctly.

Obvious caveat if I knew what I was doing I wouldn't need an electrician, but for what it's worth I did torque the "heck" out of them, like definitely very cranked on there. The biggest concern I had while installing was that the gauge was so damn thick I found that after more than one bend or so the wire got very noticeably weak, so I did my best there but my suspicion is it was already fatigued and it just finally gave up.

 

[P3dStealth]

Obvious caveat if I knew what I was doing I wouldn't need an electrician, but for what it's worth I did torque the "heck" out of them, like definitely very cranked on there. The biggest concern I had while installing was that the gauge was so damn thick I found that after more than one bend or so the wire got very noticeably weak, so I did my best there but my suspicion is it was already fatigued and it just finally gave up.

Possible, its hard to get the thick wires in the box. I broke a few strands just from moving the wires and had to cut back some.

 

[beatle]

It's interesting that even at 32A, the receptacle melted. The Leviton 14-50R I installed in October 2019 with 6/3 copper Romex didn't quite make it to 2 1/2 years before it melted. This is before I knew of Leviton's infamous reputation. I was routinely charging at 40A using a semi-permanently mounted gen1 UMC, however. The gen1 (and apparently OP's Grizzl-E connector) don't have thermistors in the plugs so they are free to heat up to melt themselves into oblivion.

I replaced the Leviton with a Utilitech from Lowes and now charge at 32A unless I need the juice in a hurry. The UMC still works after I replaced the 14-50 adapter. The receptacle no longer gets warm. This was 19 months ago.

I would also check the breaker. Just like the receptacle, I torqued the screws down as tight as I could, but over time, the heat cycles seemed to have worked their magic and the breaker began to trip from the heat a few months after the receptacle melted. When I pulled the breaker to inspect, I found the screws were not "loose" but it was possible to tighten them further at that point. (They were definitely tight when I installed the breaker.) When charging, the breaker should not be too hot to touch, though it may have a bit of warmth. It was over 140F on the surface when it started to trip.

 

[ATPMSD]

It's mind blowing that with all the complex electrical code, an outlet is allowed to be sold for a 50amp electrical supply that will catch fire if a device is repeatedly plugged/unplugged. Or the outlet isn't really good for continuous load.

Bingo! Surprisingly too many electricians do not understand the concept of the continuous load that EVs draw and, therefore, do not install an appropriate outlet or wiring. A cheap outlet like the Leviton is probably fine for intermittent loads, but not for continuous loads.

 

[jjrandorin]

I agree with you. Most of these melted 14-50 outlets are not torqued down correctly. I have been running a cheap 14-50 outlet for 4 years charging at 32amps no problems at all. I did however torque the lugs down to specs with a torque driver. It was surprising how hard the spec calls for and most people are not going to be getting there from just feel. My outlet doesn't even get warm.

The other issue with the cheaper 14-50 outlets is they are not designed to be unplugged often. If they become loose you need to toss them. I rarely unplug mine. If you do unplug it often get a better outlet.

I have no doubt the Bryant and Hubble are better. I think what's happening is the better product allows for an amount of negligence in the installation that the cheaper products do not. Also someone that seeks these high end brands tends to already know what they are doing and torque them correctly.

This is what I was trying to say earlier, but much better than I said it.

 

[Sophias_dad]

Just in case it wasn't mentioned in the thread, not all 14-50 outlets are rated for aluminum conductors, even the esteemed Hubble(9450A) and Bryant.

 

[EatsShoots]

It's interesting that even at 32A, the receptacle melted. The Leviton 14-50R I installed in October 2019 with 6/3 copper Romex didn't quite make it to 2 1/2 years before it melted. This is before I knew of Leviton's infamous reputation. I was routinely charging at 40A using a semi-permanently mounted gen1 UMC, however. The gen1 (and apparently OP's Grizzl-E connector) don't have thermistors in the plugs so they are free to heat up to melt themselves into oblivion.

View attachment 980486

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I replaced the Leviton with a Utilitech from Lowes and now charge at 32A unless I need the juice in a hurry. The UMC still works after I replaced the 14-50 adapter. The receptacle no longer gets warm. This was 19 months ago.

I would also check the breaker. Just like the receptacle, I torqued the screws down as tight as I could, but over time, the heat cycles seemed to have worked their magic and the breaker began to trip from the heat a few months after the receptacle melted. When I pulled the breaker to inspect, I found the screws were not "loose" but it was possible to tighten them further at that point. (They were definitely tight when I installed the breaker.) When charging, the breaker should not be too hot to touch, though it may have a bit of warmth. It was over 140F on the surface when it started to trip.

Dude! For a sec I was like is he reposting the same picture. Dang. Same damn thing exactly. And had the same experience with the 50A breaker before.

120V circuits seem a lot less finnicky than this, so I'm fully now in the camp of letting the electrician get me sorted, though I am very intertester in hearing his feedback once he's here.

 

[SageBrush]

New home build 2020. Had electrician run 60 amp rated wire to a 50 amp breaker. I had assumed he would run copper, but he ran aluminum because it was cheaper for him (I didn't find out till after but whatever).

In the garage he did nothing so I personally added a NEMA 14-50 in early 2021.

Do you mean that Alu was run from the service panel to an outlet in the garage, and you terminated the wires to a 14-50 receptacle ?
What AWG stranded Alu was used, and what alloy ? AA-8000 Alu alloy wire is required, and you have to know how to terminate it properly
Lastly, were the Alu wires run in conduit ?

tl;dr
Information needed
Alu wiring and DIY terminations is not a good idea for novices
Big box stores sell crappy 14-50 receptacles
Over-torquing is also a problem

Next time: Hard-wire your installation,

 

[EatsShoots]

Do you mean that Alu was run from the service panel to an outlet in the garage, and you terminated the wires to a 14-50 receptacle ?
What AWG stranded Alu was used, and what alloy ? AA-8000 Alu alloy wire is required, and you have to know how to terminate it properly
Lastly, were the Alu wires run in conduit ?

tl;dr
Information needed
Alu wiring and DIY terminations is not a good idea for novices
Big box stores sell crappy 14-50 receptacles
Over-torquing is also a problem

Next time: Hard-wire your installation,

Yes. I don't have panel open now so I cannot tell you the exact gauge of wire (or anything else about it), but I do recall it was "60 amp rated" as I had requested. It is attached to my panel and runs in walls (no conduit other than what it's wrapped in from factory), then terminated directly at the 14-50 that I installed. No pig tails or copper anywhere else.

I promise to update once electrician gives me thoughts on what went wrong as well, once he's had a look at it. He did run the exact same to our electric range as well.

 

[Unclepaul]

Cheap plug, cheap wiring, non professional installation...Maybe just a loose wire.

 

[legendsk]

Long, long ago. . . . . Aluminum was bad expensive stuff and only used for special applications. Electrical wiring was all done with copper and it was a better conductor anyhow. Terminal hardware was mostly also copper. Then they discovered a cheap way to refine aluminum - wheeee...... Aluminum was being used in lots of places and was way cheaper than copper. Most overhead power lines went to aluminum.

For a scary fairly brief time RVs and mobile homes began to be built using aluminum (at least the cheap ones). I think they caught fire and burned faster than they could build them? There were some band-aids like special grease for the terminals(???). But electrical wiring manufacturers developed better terminals that would work reliably with either copper or aluminum. Aluminum isn't as good a conductor as copper so aluminum wire has to be larger to do the same job, but even so it is still cheaper and lighter - although arguably a little more difficult to work with. Things like - copper loves to be soldered, but aluminum is a little more tricky to solder.

In the hands of someone who really knows what they are doing, either one is quite acceptable. But as nearly always true - hire a professional, it will wind up being so much cheaper than hiring an amateur.

 

[LoudMusic]

Long, long ago. . . . . Aluminum was bad expensive stuff and only used for special applications. Electrical wiring was all done with copper and it was a better conductor anyhow. Terminal hardware was mostly also copper. Then they discovered a cheap way to refine aluminum - wheeee...... Aluminum was being used in lots of places and was way cheaper than copper. Most overhead power lines went to aluminum.

For a scary fairly brief time RVs and mobile homes began to be built using aluminum (at least the cheap ones). I think they caught fire and burned faster than they could build them? There were some band-aids like special grease for the terminals(???). But electrical wiring manufacturers developed better terminals that would work reliably with either copper or aluminum. Aluminum isn't as good a conductor as copper so aluminum wire has to be larger to do the same job, but even so it is still cheaper and lighter - although arguably a little more difficult to work with. Things like - copper loves to be soldered, but aluminum is a little more tricky to solder.

In the hands of someone who really knows what they are doing, either one is quite acceptable. But as nearly always true - hire a professional, it will wind up being so much cheaper than hiring an amateur.

Boat people are real concerned about safety, for a lot of really important reasons, and they are super anti-aluminum wiring.

Electrical Systems Regulations for Recreational Boats

Electrical regulations and standards that apply to boat builders and recreational boats.

newboatbuilders.com

 

[EatsShoots]

Dude coming out later. Prelim recommendation per phone is to hardware but with copper as he hates aluminum for anything in a house except the main 200 amp connection.

He also pointed out that with a better breaker (this wasn't gfci as far as I recall but not home right now) this fire condition could have been caught before the damage, which makes sense to me. I'm not thrilled at having to spend perhaps $1500 to run a new line, so I will discuss the idea with him or a new breaker and hard-wiring the aluminum wiring to the Grizzle-E internally. He says he has seen 14-50 die in this manner. I can tell from his website and what he said on the phone he's pretty familiar with ev installs.

 

[Rocky_H]

Just in case it wasn't mentioned in the thread, not all 14-50 outlets are rated for aluminum conductors, even the esteemed Hubble(9450A) and Bryant.

Yeah, I'm going to summarize this as being the main learning point of this thread. I am almost certain that the cheap Leviton is NOT rated to allow aluminum wires for its connections. Most outlets are not. Only certain equipment is made with the right type of lugs to accept either copper or aluminum wire. These are generally panels and subpanels, and then rarely, some higher end outlets or other things.

Aluminum takes certain treatment to do it right and can only be used with the right equipment that's made for it. I think both of these conditions were not followed here. So the place where aluminum is fairly OK or a reasonable choice is a big long run circuit from one panel to another. But people shouldn't be using it for a final branch to an outlet generally.

The "why" is two main parts. Aluminum oxidizes easily, so it has to be pre-treated, like scrubbed to expose good metal before attaching, and then also needs to be covered with the No-AL-ox goop to keep air from getting to it. And the second factor is that aluminum expands and contracts more with temperature changes than copper does, so it can get loose more easily. That's why it needs certain types of lugs to try to hold that securely.

 

[Supcom]

Yeah, I'm going to summarize this as being the main learning point of this thread. I am almost certain that the cheap Leviton is NOT rated to allow aluminum wires for its connections. Most outlets are not. Only certain equipment is made with the right type of lugs to accept either copper or aluminum wire. These are generally panels and subpanels, and then rarely, some higher end outlets or other things.

Aluminum takes certain treatment to do it right and can only be used with the right equipment that's made for it. I think both of these conditions were not followed here. So the place where aluminum is fairly OK or a reasonable choice is a big long run circuit from one panel to another. But people shouldn't be using it for a final branch to an outlet generally.

The "why" is two main parts. Aluminum oxidizes easily, so it has to be pre-treated, like scrubbed to expose good metal before attaching, and then also needs to be covered with the No-AL-ox goop to keep air from getting to it. And the second factor is that aluminum expands and contracts more with temperature changes than copper does, so it can get loose more easily. That's why it needs certain types of lugs to try to hold that securely.

Looking at outlets offered by home deport, even the cheap $10 outlets are rated for aluminum wiring. I saw no Leviton 14-50 outlets, but the no-name outlets are clearly marked for both copper or aluminum. There were some single pole 50-A Leviton outlets that are also marked for both copper and aluminum.

That said, I would NOT use a cheap outlet for continuous high-current service. In fact, I would NOT use an outlet at all unless my charging equipment is made to use an outlet AND has a temperature sensor embedded in the plug. I would also not use aluminum wiring under any circumstances. House fires are just no fun.

 

[EatsShoots]

I hate to lose this

House fires are just no fun.

Where is your sense of adventure?!

It's kinda wild how close I was to quite a catastrophic event.

 

[karkrazy]

kinda wild how close I was to quite a catastrophic event.

What’s wild is how common events like this take place for first time EV owners… ask any EV owner, and they probably know someone personally that had this happen, or it happened to them.