# LiPo charger balance plug is kaput

Well, it seems that static electricity has fried my LiPo balance plug adapter. When I was plugging in my LiPo battery to it, which was plugged into my Thunder AC6 LiPo charger, a short wisp of smoke was created and the copper trace for the ground balance connection was damaged.

Pictures:

http://i.stack.imgur.com/gf5Ru.jpg An overview of the balance adapter plug.

http://i.stack.imgur.com/waGTD.jpg A closeup of the damaged connection.

Can I fix this, or would I have to buy another balance plug? If so, where should I buy one?

• Static electricity is those little sparks you can see when you comb your hair in the dark. It cannot damage copper traces. – Dmitry Grigoryev Oct 6 '15 at 13:27

That's a pretty big fault there and I doubt that static electricity could have caused that.

I recommend that you check the whole circuit for any other strange problems, just in case the cause isn't static electricity.

As for the broken trace, you can always fix it with a wire. Try soldering a wire between damaged ends of the trace and that should fix it. It may be easier to solder the wire on the other side directly between two connectors, since there is very little space left between trace breakage and the connector.

If you decide to work on the trace side, you'll need to carefully scratch off the coating on the trace without damaging the trace itself first. You might be able to solder through the coating, but in my opinion it would be best to remove in on the trace. Later you can cover the joints with insulation tape or buy conformal coating spray and carefully apply it over joints.

If you decide to work on the other side, you'll need to be careful not to use too much heat so as not to damage the connectors. The joints on the other side may be covered by some sort of coating, so test them out with a multimeter first. If you don't get continuity, try scratching or filing the coating off. You may be able to solder through it, but there's no guarantee that you will and you need to be extra careful not to damage the plastic connectors.

As for wire size, there isn't a clear reference there, but I guess that something like standard
$0.75\mbox{ } mm^2$ would be strong enough for the current. To be 100% safe, measure the size of the wires coming to the connector on the left and use such wire or larger to fix the open circuit.

• Thanks for your help Andreja. The only problem is that the reverse side of the adapter is covered in dense foam. Should I cut a little piece off to expose the other side of the board? (I'll post a picture soon) – Michael Apr 8 '11 at 23:20
• Here's the back of the adapter: i.imgur.com/cXm3O.jpg – Michael Apr 8 '11 at 23:26
• @Michael The foam could be a problem. It's probably there as an insulator, so it should be safe to cut it and remove a small piece. Just remember to cover the repaired area with something non-conductive after you finish fixing the board. Another function of the foam could be to provide a flat surface, so the bumps of the solder joints aren't exposed. It may be a smart idea to try to keep your patch as thin as possible. – AndrejaKo Apr 8 '11 at 23:58
• Okay. I think I'll try to fix the connection from the top side before cutting through the back foam. Thanks for the help again. – Michael Apr 9 '11 at 0:02