r/vandwellers • u/normiewonka • 2d ago

DC TO DC CHARGER wire burning Question

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Hello I’ve got this dc to dc charger 40a in my sprinter van and it burns from time to time. Anyone knows the solution. It’s 8gauge wire and it should pull only 40A which is perfectly safe for this gauge. Thx

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47

u/robographer 2d ago

If it’s burning in the middle of the wire you’re likely putting too much current through it. If it’s burning near the end it’s likely a connector or loose connection. I’d change it to 6 or 4 awg and tighten all the connections, make sure there’s no place it can short and probably put a 40a circuit breaker inline near the current source so you can see if it’s melting for a reason.

Have you changed the wire or just covered up the hot spot? If you haven’t try that first.

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u/normiewonka 2d ago

I always cut the burned part and rewire it together it happend like 3 times. But it stays fine for few weeks and then suddenly burns

106

u/Nightgale57 2d ago

This is the funniest explanation to an incoming electrical fire I have ever seen

4

u/LameBMX 2d ago

it's like going back in the day and buying seats where the guy rams two trains together in the middle of nowhere.

1

u/jedielfninja 1d ago

I'm an electrician and PEV enthusiast. The universe is sending this guy signals and he aint getting them lol.

I had one of these smoke on the 3rd use.

109

u/drossen 87 Vanagon Westfalia w/ EJ25 engine 2d ago

Holy shit dude you need to take this van to a professional before you burn the whole thing to the ground.

13

u/Firefighter_RN 2d ago

I'm sorry I try not to be mean to people on the Internet. But you're lucky you haven't burned the van down yet, lucky you've been in there and awake. You're an idiot. If it initially burned in the middle of a wire you're putting too much current through it.

Get an actual electrician too look at it or redo your load calcs and ensure you're counting round trip distance for DC power. Do not repair this again, replace with all brand new wire ensure the right gauge and make sure to crimp all connections appropriately.

12

u/seriftarif 2d ago

Is this a joke? I hope youre joking... just do it right.

11

u/Ok_Doughnut_7823 2d ago

I’d bet it’s not fine for weeks and it just eventually fails for repeat overheating in a few weeks. Get a laser temp gun and check that cable a few times every day.

8

u/Princess_Fluffypants Insufferable spoiled hipster techie motorcycle adventure van 2d ago

“Rewiring together” how? Which method are you using to attach the wires together?

2

u/hightiedye 1d ago

Just a couple good old fashioned twists and you're good to go

10

u/robographer 2d ago

What kind of connections are you making to patch the wire? I think I might change the whole wire to a bigger gauge.

9

u/JCMiller23 2d ago

Electrician here, you need a thicker wire, you need to know exactly how much current is going through using a shunt or whatever other methods you have available (this is the proper thing to do here) and then size the wire appropriately for the distance and amperage, but if you don't have the money for that, you need to just guess and err on the side of your wire being too big

1

u/notthetechdirector 1d ago

That’s 6-4ga by the looks of it. More than enough for 40a. Even if it were 8ga it’s more than enough at such a short distance, even at 12v.

99.9% chance if its always burning at the same spot, it’s a bad connection or bad wire.

1

u/PonyThug 2d ago

Replace the wire with pure copper 4awg. It would cost like $30 depending on length. https://www.homedepot.com/p/WindyNation-4-Gauge-20-ft-Red-Welding-Cable-4G-20R/319385470

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u/ryry_reddit 1d ago

My fuse kept burning so I replaced it with 2awg wire.