Distraction. Whoops!!!

[Granpappy]

The next time I'm setting up batteries for charging in the field and someone is chit chatting in my ear about their medical history, I might just politely tell them to go away.

I plugged in the balance leads of a pair of packs that had just come out of a heli before plugging in the power leads. Doh!

I now need to try and bridge the burnt out track.

[Jez N]

I plugged in the balance leads of a pair of packs that had just come out of a heli before plugging in the power leads. Doh!

What charger? Can't say i've ever thought about what order i plug the leads in and certainly never had an issue. Maybe i just got lucky 1000's of times in a row........

[woodsta888]

Done that before. If you have too much difference in the packs and you plug them into the balance board via just the balance connectors, all the voltage tries to level out across the balance leads. Plug IN big ones first and disconnect small ones first. Shouldnt really charge packs with more than 0.2v difference, not mandatory but good practice.

[Mike Sanders]

I always plug the main plugs in first. They can take a lot more current.

[Jez N]

They came out of the same model. They were the same discharge. Shouldn't therefore make any difference surely?

[bigpops]

Just solder a jumper wire between the affected pins on the back of the PCB. One of my parallel boards looks like that from having a plug backwards and trying to plug it in.

[Granpappy]

They came out of the same model. They were the same discharge. Shouldn't therefore make any difference surely?

Connected in series they are less likely to discharge equally then in parallel. It depends on the IR of each of the 12 cells. There was obviously enough difference in the voltage potential between cells to burn the track.

What charger? Can't say i've ever thought about what order i plug the leads in and certainly never had an issue. Maybe i just got lucky 1000's of times in a row........

TP820CD. Everything was connected but the charger wasn't running when it happened. In fact the charger wouldn't start because it detected a balance anomaly because of the open circuit on one of the cells.

[Granpappy]

Just solder a jumper wire between the affected pins on the back of the PCB. One of my parallel boards looks like that from having a plug backwards and trying to plug it in.

Will do. Cheers.

[gazmk2]

I managed to kill a powerlab MPA board doing that! I plugged in a fully charged lipo with 5 discharged lipos and they tried to even themselves out!

[Grumpy]

I now need to try and bridge the burnt out track.

Done that too many times to count. Usually the cause is being sloppy when you connect the balance plug, entering it into the socket 'wonky' and touching the wrong pins. Unless the batteries were at very different states of charge simply connecting the balance leads first wouldn't do it.
One of my boards has more solder bridges than it does copper trace It is an easy repair, just take some strands of copper wire and solder over the gap.. job done.

[woodsta888]

They came out of the same model. They were the same discharge. Shouldn't therefore make any difference surely?

Hmmm, no they shouldn't if you flew eg 12s via 2 packs.

Not concentrating, I have put one of the balance leads in upside down (just touched pins before realising) and that had same effect.

[Planehazza]

For this reason, I always plug the main discharge leads in first. Never had an issue this way so far.

[Guest]

I killed my wedding ring when it glanced a lead on my MPA with a lipo attached. Never really thought about everything becoming live just a bit complacent I suppose. Finger nearly healed after a month it got nuclear hot in an instant!



MJ

[Grumpy]

For this reason, I always plug the main discharge leads in first. Never had an issue this way so far.

That doesn't help if you touch the wrong pins when you connect the balance plug (of plug it in backward as mentioned above). It just takes a moment of loss of concentration.

[Peteski]

The next time I'm setting up batteries for charging in the field and someone is chit chatting in my ear about their medical history, I might just politely tell them to go away.

LOL! Reminds me of one of my old man's favourite sayings:- "Now look what you've made me do!!"