Core UDC-20 Charger problem

[Si Coe]

OK - I think I've blown the balancing facility on my UDC 20. It charges fine, Lipo, NiMH etc are all ok, but when you try and use the balance charge it tells you 'low cell error' and thats on every single one of my Lipos (8 2S and 1 3S). I'm sure they aren't all faulty, so I suspect the charger is the problem not the cells.
The problem is its my only charger and I need it! Since it still works, just doesn't balance I'm left with a dilemia. Do I:

1) Just use it and not worry about balancing. All the cells were balanced last week so are fine atm.

2) Carry on using it but get an external balancer like the Trakpower V-Balancer

3) Buy a cheap balance charger, use that at home to balance and use the UDC for racing in non-balance mode - something like this is what I'm thinking. Slow doesn't matter here.

4) Send the UDC off to be fixed. Means no charger for a while, but with so many cells I could do 2 meetings without it just about. But where to send, how much and how long? Any longer then 2 weeks is a problem unless I can source another charger.

So what should I do?

[stegger]

Check the balance leads fella i had a load of "NO CONNECTION" errors and like you "LOW CELL" errors. Turned out to be the balance lead which wasn't soldered properly if at all. Since resoldering them haven't had a problem in over 3 to 4 weeks

[Si Coe]

Its not the leads - 3 packs use a trakpower adapter so it could have been that, the others all have internal balance leads so they can't all have gone.

However the 3S packs balance lead was faulty and sparked when I tried connecting it to balance charge. That was when the balance function stopped working. I think the faulty balance lead caused a short that blew the balancing section. I thought it might just be the 3S port, but since the 2S batts don't work either I guess not.

[stegger]

It sounds like it's done something internally then after it shorted i would get it seen too though fella just in case. You never know if it's done any other damage

[Belsten]

I had this with mine, its beacuse the balance lead was connected incorrectly to the charger, you would need to send it back to get it fixed

[jameswilkinson7]

Mines just done the same thing Who repairs them?

[stampede vxlboy]

schumacher deal with core rc james . how long you had it i got a lipo charger for sale 2amps 25 with mains power and 12v

[jim76]

stampede, a 2A charger is no good to a racer who needs to charge a lipo in 45 mins. As i said elsewhere, it is more suited to micro racers, advertise it on UK-microRC

[jameswilkinson7]

Thats right... I need to charge at 5 amps at a meeting

[IceMike]

some thing happened to mine at the national last week, got some magic smoke come out the balance port, just havent had a chance to send it off yet.

[stampede vxlboy]

buy a imax b6 lipo charger top charger

[MikePimlott]

All that happens when you cross the balancing leads is it blows the tracks off the little balancing PCB (the one with all the white sockets on) the tracks are very small and cant handle the current of reversed polarity.

All i have done is desoldered and moved the 2 cell socket (3 pin) to another point on that card (as all the sockets are in parallel) one where the tracks were not damaged.

All works fine again.

[paulc]

just got one of these chargers the fan is soooooo loud was thinking of taking it apart to have a look is it just my charger or are they all like it

paul

[madwestmo]

mine does this all the time with that error , just go onto the balance charge bit and change it from ''2S, 3S'' etc to ''AUTO''

That should fix it mate

[MikePimlott]

Originally Posted by paulc

just got one of these chargers the fan is soooooo loud was thinking of taking it apart to have a look is it just my charger or are they all like it

paul

When i got mine the fan was loud and the speed of the fan was not consistent, i removed it and found the bearing in the fan had so much play is was preventing it from running correctly. i replaced it with one from RS and thats all ok now.

[Si Coe]

Originally Posted by madwestmo

mine does this all the time with that error , just go onto the balance charge bit and change it from ''2S, 3S'' etc to ''AUTO''

That should fix it mate

Just tried that, and it sort of works. That is it doesn't show that low cell err, but it does spend 10mins (literally) with the 2 in the BL2S line blinking, meaning it takes ages to auto detect. An issue as its only charging at 0.1A during that time.
However since it does now balance, and I only balance charge at home (I prefer normal charging at the track, its just quicker) I guess I'm fine for the time being.

Thanks!

[madwestmo]

hopefully it should get quicker for you as mine blinks for around 1minute now before finding its 2S

I just do like your doing , balance at home and normal charge when at the track

[jenski]

I had mine fixed by Schumacher a few months back for £15, as it is not covered on the warrenty.

[jameswilkinson7]

Originally Posted by MikePimlott

All that happens when you cross the balancing leads is it blows the tracks off the little balancing PCB (the one with all the white sockets on) the tracks are very small and cant handle the current of reversed polarity.

All i have done is desoldered and moved the 2 cell socket (3 pin) to another point on that card (as all the sockets are in parallel) one where the tracks were not damaged.

All works fine again.

Yep... fixed mine by re joining the tracks with a small piece of wire... Its a little tricky but it works.