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Breaker Fuse Blew with Mobile Charger

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Was charging my MY Long Range at my sisters house over the holidays. On the last day I used my mobile charger using the 14-30 adapter, and plugged into her dryer outlet. Everything seemed fine and it began charging right away. To be sure, i checked the app and it Har automatically adjusted the amps max to 24A.

I then stopped the charging from the app because I wanted to use Scheduled Charging so that it would be preconditioned by the time we hit the road (it was cold out).

So, before i went to bed, battery was around 30% and scheduled for 100% by 9am. But when I woke up, I saw an alert on my phone saying that charging stopped and to go check the car. At the car the battery actually charged all the way up to 88%. But the mobile connector was not lit up anymore. I thought no big deal, the fuse maybe tripped. But the fuse was blown! See pic.

Any ideas why this might’ve happened? And what can i do to prevent it in the future? I hope it’s just a dryer fuse that needs replacing, but from the looks of the fuse maybe some wiring also got burned in the walls?

Also, it’s pretty embarrassing!
 

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That breaker may be defective, or more likely there's a bad connection at its lugs. It also looks like the wrong breaker(by far) for a 14-30, since it should have a 30 amp breaker instead of a 50 amp breaker.

Additionally, that breaker looks very old, and has weeds or other garbage growing out of the cracks near it. If the same stuff is inside the panel(or even the breaker!), the breaker may be misbehaving.
 
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That breaker may be defective, or more likely there's a bad connection at its lugs. It also looks like the wrong breaker(by far) for a 14-30, since it should have a 30 amp breaker instead of a 50 amp breaker.

Additionally, that breaker looks very old, and has weeds or other garbage growing out of the cracks near it. If the same stuff is inside the panel(or even the breaker!), the breaker may be misbehaving.

Oh I see. So you would say that the breaker looked like that before it was blown, and not “because” it was blown.

Also, would it still be okay to replace it with a 50A and continue to use the dryer and on occasion to charge my Tesla with the 14-30?
 
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Oh I see. So you would say that the breaker looked like that before it was blown, and not “because” it was blown.

Also, would it still be okay to replace it with a 50A and continue to use the dryer and on occasion to charge my Tesla with the 14-30?

The breaker needs to be sized correctly to the cable and outlet that are attached to it. The breaker is what keeps the wire and outlet from overheating and catching on fire. When in doubt always use a smaller breaker.
 
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Oh I see. So you would say that the breaker looked like that before it was blown, and not “because” it was blown.

Also, would it still be okay to replace it with a 50A and continue to use the dryer and on occasion to charge my Tesla with the 14-30?
The breaker probably was old and tired before it was blown. TBH, it doesn't look like it is in the 'tripped' state in the picture, but I assume it had already been reset. My best guess is that the lugs overheated due to a bad connection and the heat traveled into the breaker. You were using less than 50% of the breakers intended capacity.

It should be replaced with a 30A breaker. Chances are good that someone ran a wire capable of 50 amps out to the outlet(at the time perhaps a 14-50), and later someone decided they needed a 14-30 for the dryer but didn't update the panel, but that just a guess. In any case, the 14-30 outlet is only rated to move 30 amps so you should definitely not put a 50 amp breaker in.

I see there's a handy 'spare range' 50 amp breaker next to it, which is similarly strange.
 
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The breaker probably was old and tired before it was blown. TBH, it doesn't look like it is in the 'tripped' state in the picture, but I assume it had already been reset. My best guess is that the lugs overheated due to a bad connection and the heat traveled into the breaker. You were using less than 50% of the breakers intended capacity.

It should be replaced with a 30A breaker. Chances are good that someone ran a wire capable of 50 amps out to the outlet(at the time perhaps a 14-50), and later someone decided they needed a 14-30 for the dryer but didn't update the panel, but that just a guess. In any case, the 14-30 outlet is only rated to move 30 amps so you should definitely not put a 50 amp breaker in.

I see there's a handy 'spare range' 50 amp breaker next to it, which is similarly strange.
Thank you for the help! Unfortunately my brother in law already replaced the breaker with a new 50A one. I guess he assumed that the original one was correct.

Anyhow, do you think it should be fine with the 50A breaker, as long as someone does not try to plug in anything more powerful than that dryer? As for plugging my Tesla back in, should that be fine too, so long as I keep it at 24A in the app, which it seemed to do automatically? I mean they never had issues with the dryer being plugged in during the 8 years they’ve lived there. It wasn’t until I came along and plugged in my EV 🤦‍♂️
 
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Thank you for the help! Unfortunately my brother in law already replaced the breaker with a new 50A one. I guess he assumed that the original one was correct.

Anyhow, do you think it should be fine with the 50A breaker, as long as someone does not try to plug in anything more powerful than that dryer? As for plugging my Tesla back in, should that be fine too, so long as I keep it at 24A in the app, which it seemed to do automatically? I mean they never had issues with the dryer being plugged in during the 8 years they’ve lived there. It wasn’t until I came along and plugged in my EV 🤦‍♂️
It should be 'fine', in that anything that plugs into the 14-30 isn't allowed to take more than 30 amps. The problem comes when there's an internal failure of the dryer that makes it takes 50 amps and it doesn't trip. If we assume the wiring in the wall is rated to take 50 amps, either the outlet or the cord or even the guts of the dryer will overheat and something will fail.
 
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In the picture I had already tried putting the breaker back in the ON position. But it did not matter since it was blown—it had no snap to it, if you know what I mean.
Just to be clear.... if the circuit breaker had tripped then you need to put the switch into the OFF position first (reset) before you can "snap" it back into the ON position. And breakers do not have any kind of "fuse" inside them. It is a mechanical switch that, if everything is working correctly, switches itself off when it detects too much current flowing through it.
 
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Just to be clear.... if the circuit breaker had tripped then you need to put the switch into the OFF position first (reset) before you can "snap" it back into the ON position. And breakers do not have any kind of "fuse" inside them. It is a mechanical switch that, if everything is working correctly, switches itself off when it detects too much current flowing through it.

Good clarification -- I meant breaker, not fuse.

I did put it in the OFF position, and then back to ON. And still there was no snap, not even any spring to it. So not only did it trip, but it's guts probably burned or broke somehow.
 
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Anyhow, do you think it should be fine with the 50A breaker, as long as someone does not try to plug in anything more powerful than that dryer?
Replace it. A 50A breaker is very likely oversized for the wire in the wall and is a fire hazard. The fact there was a 50A breaker in the first place screams DIY wiring by an unqualified individual. I’d blame that rather than the car.
 
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Thank you for the help! Unfortunately my brother in law already replaced the breaker with a new 50A one. I guess he assumed that the original one was correct.
Ok look, here's the deal. *EVERYTHING* in the circuit needs to match or you run a fire risk. Do you get that? I'll explain. 30 amp breaker feeds a 30 amp outlet (L14-30 Dryer Plug) with # 8 wire (a bit oversized in case of voltage drop). That's what you need for a 30 amp dryer circuit. Now a 50 breaker needs #6 copper wire to feed a NEMA 14-50, 50 Amp outlet. Now you say you put a 30 amp receptacle at the end of the replaced 50 amp breaker. So here's what happens, your Tesla pulls more than 30 amps, but *NOT* more than 50 amps. Breaker doesn't trip, wire is fine, but your 30 amp rated outlet starts to melt because the amperage is to high for the rating of the outlet. Boom, FIRE. 50 amp breaker still is not tripping. Fire gets bigger. You can have bigger wire as long as the breaker and the outlet ratings matches. Right now your breaker doesn't match your outlet rating. That's a fire hazard. Change it or don't. Plug your Tesla in or don't. I'm a 27 year Union Electrician, I just want you to know the danger of what you have in place. I'm not saying it WILL catch fire......but it could. Isn't that enough? If I was a betting man I'd bet the wire size on both the the 50 amp breakers are #8 Copper and should be switched to 30 amp breakers and you'll be fine. A good electrician should be able to come out and quickly tell you for a small service call. Good luck friend.
 
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Replace it. A 50A breaker is very likely oversized for the wire in the wall and is a fire hazard. The fact there was a 50A breaker in the first place screams DIY wiring by an unqualified individual. I’d blame that rather than the car.
Excellent point! If the wire size going to the 50 amp breakers is #8 copper and not #6 then the wire, like the 30 amp rated receptacle, is now the weak point and can catch fire when the oversized 50 amp breaker does not trip. That wire is in the wall of the house. When you see electrical fires in the news, these are the most common causes. Understandably, most people don't understand the potential for extreme failure when electrical components are not installed per code. It's for safety first and foremost.
 
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Excellent point! If the wire size going to the 50 amp breakers is #8 copper and not #6 then the wire, like the 30 amp rated receptacle, is now the weak point and can catch fire when the oversized 50 amp breaker does not trip. That wire is in the wall of the house. When you see electrical fires in the news, these are the most common causes. Understandably, most people don't understand the potential for extreme failure when electrical components are not installed per code. It's for safety first and foremost.

OK. This is why I came here! I'll have them switch that 50a breaker for a 30a one.

After that, I should have no problem unplugging the dryer to charge my Tesla on that 14-30 outlet, correct? I still don't know why that 50a breaker blew to begin with, but luckily it did.
 
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OK. This is why I came here! I'll have them switch that 50a breaker for a 30a one.

After that, I should have no problem unplugging the dryer to charge my Tesla on that 14-30 outlet, correct? I still don't know why that 50a breaker blew to begin with, but luckily it did.
Yes, if your breaker size matches your plug rating you'll be fine. 30 amp dryer plug, 30 amp breaker. Good to go. Breakers do go bad. It's rare but it happens. I'd still suggest you have an Electrician come look at the bad breaker and survey the panel to judge if there's any damage to the wire or the panel it self. Just a suggestion.
 
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Look at the manufacturer of the fuse box. If it was installed in the 1950's or 60's it might
be Federal Pacific. If it is, be aware those fuse boxes are dangerous and have burned
down houses. If it is Federal Pacific the problem with overheated wires is not
surprising. There's a long story available on the internet about those fuse boxes
and how they achieved UL approval -- check it out.

One clue is, with the breakers switched ON and the 4 screws holding the front panel
on removed, can the front panel be removed without interfering with the
any breaker switch?
Any interference is a tell-tale that it is Federal Pacific (and dangerous).
 
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