Trakpower Lipo Problem

[markwilliamson2001]

Hi,

Last night I was using my two 4900 Trakpower stick packs (the gold ones).

Everything seemed to be fine during the racing, but I top up both sticks after giving the packs 5 mins to cool down a bit.

One of the packs, when I put it on charge kept coming up with E2 errors on my trakpower charger (used with a TP balancer).

Looking at the balancer, it seems that maybe one of the cells has become over discharged, while the other got over-charged (The balancer was changing between a flashing red light on the status meter, then changing to fully charged with a flashing green light, the pack is not swollen though.)

When I checked the whole pack with a multimeter, it was reading 7.75v, so I figured one of the cells may have died inside the pack...

To be honest, its not too bad, as I have used them for about 18 months now...a replacement may be the only answer (I don't fancy opening the case up to be honest )

Anything I can do to try and revive it, or is it a bin job (once put into salted water of course!).???

Thanks,

[bodgit]

Give the customer support team a ring, they would best advise you.
http://trakpower.com/index.asp?page=support.asp
Cell Balancing...
Cell balancing is the process of leveling or equalising the individual cell voltages in a pack as an analogy to equalising the capacity charge state. TrakPower packs come balanced from new as part of the cell matching process. In use, this process is normally practiced whilst charging. Cell balancing helps maintain the performance and life of a LiPo pack by preventing a progressive drift in the charge state of the cells and ultimately exposing one or both cells to overcharge or undercharged states. Additionally balanced charging optimises the charged-in capacity. Some balancers including the TrakPower V-Balance have a charge-though safety feature that halts charging when balancing cannot prevent the overcharge or over-discharge of one or more cells.

[markwilliamson2001]

Cheers mate. Thanks for your help.

[mark christopher]

what voltage do you have between the balance pin a + and
balance pin and -
it could be your balancer

you can connect your charger above and charge at 1 amp to get a voltage reading or check the charge of each internal cell ( charger will need to be set to 1 cell and dont use the balncer)

also check the ballancer conections inside the plugs there is a slotted grub screw that can come loose and make sure the small 2mm plug is soldered ok and not a poor connection
defo not bin fodder at this moment

[markwilliamson2001]

Thanks mark, could you describe the steps you mentioned in a bit more detail.
Esp. Checking the pack using 1 cell setting on the charger woukd be good, and how do i check to see if its a poor connection on the balance pin without disassembling the whole pack?

Habe to say the pack was fine during the run, before putting it back on charge....

Thanks,
Mark

[markwilliamson2001]

You have PM Mark Christopher.
Cheers
Mark