bc-8 not charging to 4.2v/cell

[cudaboy_71]

i've had 2 bantam bc-8 chargers for +5 years. Both have been great.

Today I was charging two 5300mah 5s packs. One of the chargers beeped complete, but the cells were only charged to 4.17v each. I pulled the pack, checked the IR (nominal---i keep a log), and plugged it back in to the charger again. It ramped up to 1.3amps (set for 5.3 or 1C), then it ramped back down like it was completing a charge cycle and beeped complete again.

I waited until charger 2 completed its charge (which it did fine to 4.2v/cell). Plugged in the 4.17v/cell pack and it completed its charge just fine, up to 4.2v/cell.

This is the first time I've had a charger act up. I'll be keeping a close eye on it. Unfortunately that was the last pack to charge for the day...everything's ready for tomorrow now. But, i'm curious... is this something that happens from time to time? Or is something wrong with the charger?

[TractorMan]

I have a BC8DX and a BC8 charger and both of them have had problems with balancing at one time or another. Another common problem was to have the charger remain charging the batteries at .01amp forever and not terminating the charge. I sent the BC8DX back to Devon at RC accessories once and he replaced a balance board in the charger for me and checked all of my external balancing connectors. (Devon is a great fella). Even though he said everything checked out I still had trouble. I finally noticed that some of the new chargers coming out do not use external balance boards, the balancing tap from the battery plugs directly into the charger. Makes a lot of sense when you think about it. The best way to eliminate problems is to eleminate the amount of connections. Long story short. I trimmed the small tits off of by battery balancing plug so I could plug them directly into the chargers balancing port and what do ya know. Every battery that I own balances perfectly now and the charger never hangs anymore, it always terminates the charge when complete. I even saved a few batteries I thought were gonner's. GET RID OF THE BALANCING BOARDS! They are problems waiting to happen.

[cudaboy_71]

thanks for the tip on the balancing boards. interestingly enough (perhaps just out of laziness) i found that all my batteries (turnigy, hyperion, gens ace to name some) all fit perfectly in the side of the charger without a balance board. the only pack i use a board for is my TX pack that has a TP tap.

that said, the issue i had happened with the pack's tap plugged directly in to the side of the BC-8.

[TractorMan]

Well I guess that my page long reply wasn't much help. You seem to be ahead of me on this stuff. As far as the Thunder Power Lipo goes, you can get balance tap adapters from Hobby King really cheap. They are short and will then allow you to plug directly into the charger. This is what I do. It does raise the connections by one but it is still fewer than you would have using the balancing board.