Query on Accucell 6 and small batteries

[dualarrow]

Hi,

I have an Accucell 6 and it works great for larger batteries (1800mah) but it may be having some problems on smaller ones. I have some 800mah 3s lipo and 500mah 2s lipos (2 of each) and both fire off alarms on the Accucell when a fully charged battery is connected. Sometimes I see "Damaged" and other times I see "Over Voltage" (going on memory for the exact wording).

I know my batteries aren't faulty as they all have the correct voltage for their cell counts when fully charged and function correctly in a plane.

I have been charging them with a smaller charger that takes quite some time to fully charge them.

What I have noticed is that if I put my multimeter across the battery then connect it to the charger, the voltage looks to go up about 2v wheres on the larger packs, it doesn't go up anywhere near as much.

Has anyone used an Accucell 6 to charge packs of 800mah or smaller ?

Thanks,
Andrew

[RCModelReviews]

The smallest I've been charging is 1000mAH but I've got some 450mAH packs at the workshop, I'll try charging those and see what happens with my Accucell 6.

[dualarrow]

Hi,

Just an update.

I'm starting to suspect the accucell 6 now. My 1800mah 3s's seem to be failing on it receiving an initial 4 amps before the charger fails it. I'm sure the batteries are ok as I was flying with them earlier today. The other possibility is my power supply, though it seems ok. It's running a smooth 13.78v and doesnt budge with the load of the accucell. I don't have a scope so I can't tell if there's any noise on it. I'll have to do a bit more testing with it on a car battery and see how it goes.

Andrew

[Sid Sideslip]

Try checking the voltage calibration of the Accucell with your multimeter. Hold Enter and left arrow together at power up to go into calibration mode.

[dualarrow]

Yep, I have tried to calibrate it, but I ran into a few problems with that too. I tried to calibrate it on a 500mah 2s lipo. Interesting.....
I couldn't get it to adjust properly. The multi had the right voltage, but in calibration mode it was way too high. Shortly after I could smell burning so shut everything down and left the lipo outside for the night just in case (it felt like it was the power leads that were heating up). It seems to want to apply about 12 volts across the pack regardless of the cell count and with quite a few amps. The 500mah 2s was not happy with it. The pack is still functioning. I tried with a 1800mah 3s lipo and got more sensible reading, but only if I measured the voltage across the pack while it was connected to the charger. It should be measuring correctly, but I wonder what the correct procedure for measuring should be (I followed a youtube tutorial).

The more I look into this the more I'm starting to suspect the charger has a fault. I got the same results on the 500mah 2s when I used the 1800mah 3s as the power source to the charger.

Cheers,
Andrew