Turnigy accucel burnt fix

[rogerjiangcf]

Today, I connected a battery to the input of the charger to power up the battery and connect it to the output of the battery to discharge it. During the battery checking stage, after the start button was pressed, something burnt up. Afterwards, the charger will say connection break at the battery checking stage before charging.
Everything else works just fine

Is it fixable? If yes, which component needs to be change in order for the charger to work again?

[TriodeTiger]

Learning exercise: Why not open it up and investigate? It should be not widely different from other products. Is a resistor scorched? A MOSFET charred? You said something burned so it should look obvious! Where is this burnt component on the schematic, after finding it? What is the part number on the part if available, or in the schematic? etc. etc.

Is it fixable?

Almost anything broken is fixable, it just depends on how much you want it fixed, how much time or money you have.

[Legit-Design]

Today, I connected a battery to the input of the charger to power up the battery and connect it to the output of the battery to discharge it.

I also tried this with a car lead acid battery, worked fine when discharging it with the internal resistor. Didn't work so fine when I tried to "charge" the battery from itself, my thinking at the time was since it works fine when discharging then I could discharge it faster by using it's own power to "charge" it. I suspect mine has some burnt tracks that glowed red for few seconds. Luckily I got two of these just differently branded. The broken one of mine also says "connection break" and wont start charging, so nothing major can be broken. Dave did some time ago a teardown of a similar unit, they are pretty simple.

[Neverther]

Mine did that on first high amp use, turned out to be crappy connection in the banana plug, craved the plastic off and resoldered the plug.

Unplug and measure the wiring first.
Then check for burned stuff inside the unit.

If the wire was bad, it could have protected the board itself.

[IanB]

OK, I'm getting a horrible idea from this thread that people have tried to connect the same battery to the input and output of the charger at the same time?

Just don't do that, mmkay? Just don't. Bad idea. Very bad.

[rogerjiangcf]

Learning exercise: Why not open it up and investigate? It should be not widely different from other products. Is a resistor scorched? A MOSFET charred? You said something burned so it should look obvious! Where is this burnt component on the schematic, after finding it? What is the part number on the part if available, or in the schematic? etc. etc.

Is it fixable?

Almost anything broken is fixable, it just depends on how much you want it fixed, how much time or money you have.

It might be simple for you but not for others. I opened up before I started this thread but I just can't find the burnt component(s). I know that something in the middle of the board smell "funny". Sometimes a burnt component might not look burnt from the outside and you should know that.

[rogerjiangcf]

From what I know, I think it will probably be a voltage regulator since that's the component that makes the input voltage different than the output voltage. Since the charger says "connection break", I'll say a voltage detector is burnt and it could be part of the micro controller. Anyone agrees with me? Anyone got any guesses?

[IanB]

Guessing is not usually very efficient. You need a schematic of the charger circuit, which perhaps you can reverse engineer from the circuit board. Then you need an understanding of how it works so you can deduce what voltages should appear where. Then you can trace the circuit with a meter and locate where the voltages are not what they should be. That will help you to narrow down the probable failed components, which you should replace. Repeat that process until the charger works again.

Since the charger is inexpensive it may be easier to buy a new charger.

[Bukurat]

Which model is it, the 6 or the 8?

If it's a 6 there is a teardown and an link to some circuits here
https://www.eevblog.com/forum/blog/eevblog-397-turnigy-accucel-6-charger-teardown/

[Seekonk]

Almost totally unrelated, but I was given a defective Turnigy 130A power meter.  When I tested it on 12V, found that the regulator was shorted and the micro was seeing 11V instead of 3.3 volts.  And it likely had this voltage on it for a long time. I powered it up with an external 3.3V regulator and it worked fine, still using it.  I was amazed that 11V didn't blow the micro off the board.