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The Duralast 750 Jump Starter is notoriously fickle when charging with the built in charger. I did a quick 'mod' to add an SAE connector that connects into a digital battery charging unit for.
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TV Repair / replacing electrolytic capacitorsTry first. Please too - especially before posting that parts 'look OK'.follow advice at your own risk. High voltages are potentially dangerous.
If in doubt seek an expert. Rules.Read the sidebar and our BEFORE posting!.On topic questions only - see Rule #1.The post title should summarize the question clearly & concisely.Extra rules apply to questions on vehicle electronics -.(removed).' Jokey' comments that don't materially contribute to the topic may be deleted. (This isn't ).Typical questions'Trying to locate a replacement for a blown MOSFET'Why doesn't my Op-Amp circuit work as expected?' 'How do I calculate the bandwidth of an amplifier?' 'How can I take high voltage measurements with my oscilloscope?' Alright so long story short the charger stopped working after the leads got shorted outBrand DuralastModel number is DL-50First thing I assumed was a fuse blew out.But I get the chirp from my multimeter when I check them.
So I'm assuming they are good.Poked around a bit more and it appears as though nothing is receiving any power.Now I know that there is power going to the switch from the power cord. Because I got shocked lol.I'm taking pictures now.Any help would be greatDuralast battery chargerThe bits of blue tape mark the two fuses I can seeDuralast battery charger. I'd guess that the pretty coloured wires are going to the mains input side of the transformer via a 120/240 slide switch. If so, it looks like there might be a thermal fuse embedded in the core - with terminating wires coming out far right (next to the yellow wire) andsecond from the left, next to the black wire. If that's open circuit - you have your answer. How long was it running short-circuited by the way? Just a quick splash or seconds/minutes?If there's voltage across the primary and the thermal fuse is intact, then the odds are that the problem is on the secondary side.
Somewhere in the black areas inside there will be a rectifier - probably bolted to the metalwork. That would be the next thing to isolate and continuity/diode check. If it isn't the thermal fuse, or one of the other fuses, then the rectifier is next most likely. Nope, on top of the transformer. There's the big silvery rectangle showing in the centre of the photo. Just below it appears to be two shiny wires coming from the terminal strip and disappearing down a hole just next to the shiny rectangle.
I'd reckin that they were going to the thermal fuse. It blows when the transformer windings get too hot. Has better eyesight than me, working out that the splodge on the back is the rectifier. It just looks like a splodge to me.Twenty seconds, erm.
It's a bit iffy - I'd hope that it wouldn't blow the thermal fuse that quickly, but it may have.Edit: twnty past midnight, here. Time for bed. I'll be back in around 9 hours or so (some of us need beauty sleep more than others).
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