Trakpower 4900 udc 20
 

Hi, I have just tried to charge my 3 week old stick pack on my core udc20. All i get it it starts to charge for approx 5 secs then it comes up with batt vol err cell low vol. the pack has been run last thursday with no problems, and stored un connected to anything, with well over 7 volt in..... It wont charge... I have a core lipo 3250 and that has no trouble. Is the trakpower goosed? HAve spokent o the shop where I got the lipo and they told me to phone flighttech, phoned them and all I get is an answer phone... :confused:.. help.

Are you trying to balance charge it with no balance harness connected?

The Core lipo has the right balance lead for the charger but you need an adapter harness for the Trakpower 2mm plug.

Yeah, using the harness too..:(.. like i said, it was all working fine last thursday....must have a dodgy lipo pack I think... I may be wrong..?

does it charge without using balance (balance lead removed from charger too?) whats the voltage on each cell? plus to balance and minus to balance?

trakpower/.flightpower/flighttech are very busy at the min suffering form staff off work

Give Trakpower a ring, they are very helpful.

Most likely the battery is a tad lower than you thought and the charger/balancer is being a little over sensative. I'm sure Mac or any of the tech boys at TP will find you an easy fix.

Or Mark C..... he's quite handy aswell :)

Have you got a meter to measure the pack's voltage independantly of the charger? You can measure each cell via the balance port and see what they are each reading.

trying to sort out multi meter to test individual voltages now....will update asap...

As far as I can tell I have everything set up correctly, I have set the meter to 20, under dcv, and the results showing 1404?? no dots in between to indicate voltage? dont know if the meter is any good?.. used the same settings on the other lipo i have and it shows 1567? stressed now..lol

right, changed the battery in the multi meter, the pack is reading 7.34v but, not getting any readings at all from the individual cells? the meter stays at zero....?

Hmmm, have you tried charging without the balancer?

I wonder if the balance port has gone open circuit for some reason then?

Not tried that, a little pessimistic to mess about with it if it's faulty. Dont want it to go bang or anything...:(

Just tried it quickly for about 30 seconds.. it all seemed fine charger did not cut off....., I guess the balance "port" has gone for some reason... strange...!

Certainly sounds like it! Time to call in the warranty then. How annoying!!!

lipo
 

i had this, turn down the ampage on the core to under 1 amp and try it leave it on that setting for 5 mins or so then try to charge normally i think the volts are a tad low.

if you are using the core udc 20 charger, I have had the same message even with band new lipos, when I queried this with microtech, they advised me that schumacher had informed them that this fault occurs through incorrectly installing the balance leads and to return the charger to schumacher, which I havent done yet

to measure the volts of each cell put red probe in the + and black probe in the centre balance port ( if digital meter) then swap the red probe the the - hole, you should get same reading as red to + but will be minus.
if you have no readin posible a poor internal connection.

what balance lead do you have for your core? bought or home made? fair to say your charger is ok.

you have two options, return the pack to shop with multimeter in hand as your evidence, or return it to trakpower who will replace it, MAC is in australia for a month so make to attention of IAN, include your contact details and they will sort you out, print and enclose this thread and mention this what ive told you to do re voltages.


please note as above, they are at the min extreemly busy, so bear with them.
pm me and ill give you ians email if you want to pre email him

i belive it can pop the track on the pcb board inside, i had a similar fault while playing on my bantam :blush: repaired it my self tho :thumbsup: but as his other pack is ok im sure thats not his concern

Mine did exactly the same 4weeks ago whilst charging on my Bantum BC6 once I connected the Balence lead i could charge normally, some fault somewhere but i have raced twice since then no problems. If i try to charge without balance lead it come up with CELL VOLTAGE ERROR. After charging i checked the readout of each cell and both were 3.7 so whi knows must be a Trakpower fault.
One interesting thing was that i change my ESC to a LRP TC and X12 this combo sucks the LIPO dry to 6.99 at cut off, next week i had this fault !!:confused:

your fault is that you have left the balance lead in the charger and not in the pack, the charger knows this and gives the error message, unplug balance lead from pack and charger and the message will disapear!!

Hi Mark

Sorry pal this makes no differance any other ideas ??