cheap charger heads up(out of balance)

[stanmondz]

i run a imax B6 and a hobbyking eco 6-10. according to those chargers,all my packs are within a tenth of balance.

i charged up and ran yesterday, everything had short run times, plan on runnin again this weekend so i started chargin packs when i got home. all my packs took half or less than there rated capacity, somethings wrong.

so today i started checking each cell in each pack, all my packs were way out of balance.

im now recharging each cell individually through the balance tap.

got so far the worse one chargin now, its up to 722mah and still charging.

wish i would have caught this sooner, i threw 2 2s packs in salt water last night. im sure one of em was done, few seconds after starting charger, it kicked off and said full 8.40 volts

if you have a cheap charger and dont already know this about em, get you a good VOM meter so you can check your cells once in awhile

[jado6006]

This is a psa on why not to buy a cheap charger. With all that's at stake, (especially with lipos) i don't know why you would anyway. There are a ton of ways to skimp, but something that could potentially re-model your house for ya (or worse), aint one of'em.

[stanmondz]

i know. im lookin at chargers now. dont got the coin to buy new ones right now, but i will be babysitting the packs

[Exocaged]

I have a buddy with the imax b6 charger, I'll pass the word on but he hasn't had any issues yet, that he knows of.

I hope my Hitec X4 is a good one as it sure wasn't cheap. I also have a Venom Pro Charger that's served me well so far.

[Johnnysplits]

Finally someone gets it!! I always preach about not using cheap charging equipment due to the fact that most of the time they are very inaccurate, low powered, can't read I.R., no charge/discharge graphing capability, and limited on safety features. A lot of people say my system is way overkill, but I'll never need to upgrade again...even if I ever get that 600 class heli that I've been eyeballing in which I would have a small pile of 6s lipo's to charge repeatedly during the day. Cheap batteries.. yes, cheap chargers.. no

[stanmondz]

Originally Posted by Johnnysplits

Finally someone gets it!! I always preach about not using cheap charging equipment due to the fact that most of the time they are very inaccurate, low powered, can't read I.R., no charge/discharge graphing capability, and limited on safety features. A lot of people say my system is way overkill, but I'll never need to upgrade again...even if I ever get that 600 class heli that I've been eyeballing in which I would have a small pile of 6s lipo's to charge repeatedly during the day. Cheap batteries.. yes, cheap chargers.. no

thats how most of us learn, got to pull it on our heads first.
hopeful i saved my packs,dont got the loot for a fresh pile of batteries right now

[Exocaged]

with a cheap charger, couldn't you just use one of those lipo checker things you plug into the balance plug? I always look at the cell values, when I get one that is more than .02v different it gets a balance charge on the next charging. I run my stuff a lot and all my batteries have 15+ cycles on them. Some may have 40 or more.

[Johnnysplits]

Originally Posted by stanmondz

thats how most of us learn, got to pull it on our heads first.
hopeful i saved my packs,dont got the loot for a fresh pile of batteries right now

The last cheap charger I had ($90 which isn't exactly cheap) always overcharged my batteries, gave individual cell readings that were off from dvm and Hyperion battery century. The biggest thing is that if you can't read I.R. of the individual cells, you'll never know the state of performance or even when your battery is on the edge of lighting up. Here's something for ya...I had bought a RTF 450 class heli. The 3s lipo it came with, no matter what I did, after charge and after discharge, always had a very low cell. So I stopped using it. After I got my new charging equipment, I tried doing a few charge/discharge cycles on this crappy lipo. Let me tell you it brought it back to like new condition!! Now after a charge, every cell is exactly the same voltage...and all cells discharge at the same rate as well. It has very low I.R. too.

[stanmondz]

i always balance charge mine.
i got one of those little cheap volt checkers.
i got packs with 100+ cycles on em

this wont happen with one charge, it adds up after many, for the most part, we wont notice a 5 minute lose in run time.comp guys will but trail guys wont.
but when your loosing a few MAH per charge from the same cell everytime, that low cell will cause pack voltage to dip and trigger the LVC when a load is on the pack. we see it as "where did my power go, that pack just came off the charger" they after the load goes away back on flat ground, rig seems to be ok.until loaded again

we write it off as a tired motor, or drivetrain binding, rebuild/replace motors,tear down,clean and grease drivetrain, all helps, but problem still there. then we run a borrowed pack same size or smaller than what we had and rig runs better than it has in a long time. throw away our battery and buy new ones, problem solved, bad battery pack right? then many cycles later, same thing.

thats how i was thinking, but im on vacation this week and was bored stuck inside due to rain and figured id poke around some with a good volt meter. my chargers and volt checker are both way off on voltages.
i put 780 mah into 1 cell of a 5700mah saddle pack, that was my worse one, thats after my charger said it was at peak, volt meter read it at 4.25/4.10, not off much,but that weak cell will drop pack voltage once loaded enough to hit cut off fast, leaving half or more of your pack unused, then the high cell will trip off your charger sooner than it should,only taking part of the charge it use to.

all in all, chargers are a penny smart,dollar stupid purchase, we saved some up front,but how many good packs,motors,esc's have we thrown away because there "bad" when all the while its our cheap chargers that are the problem??

im the king of justifying cheaping out on something, but i will be getting a quality charger as soon as money permits

[stanmondz]

what charger you runnin Johnnysplits?

[Solitaire]

You absolutely do not have to spend a fortune on a decent charger. All you have to do is your homework. Just have a look around RCGroups and you can find feedback on just about any charger out there and then make your decisions.

[Charlie-III]

Originally Posted by stanmondz

I always balance charge mine.
I got one of those little cheap volt checkers.
I got packs with 100+ cycles on em

That's how I was thinking, but I'm on vacation this week and was bored stuck inside due to rain and figured I'd poke around some with a good volt meter. My chargers and volt checker are both way off on voltages.
I put 780 mah into 1 cell of a 5700mah saddle pack, that was my worse one, thats after my charger said it was at peak. Volt meter read it at 4.25/4.10, not off much, but that weak cell will drop pack voltage once loaded enough to hit cut off fast, leaving half or more of your pack unused, then the high cell will trip off your charger sooner than it should, only taking part of the charge it use to.

OK, what was off, the charger cell voltage value, the "volt checker", your meter?

Just curious. I guess most of us "assume" our chargers etc., are accurate, I will admit I've never compared them.

I review the cell voltages a number of times while charging my packs (almost all are 3S, ~450mah to 1300mah) using the display in my Venom ProCharger.
Between my son & I we have 4, 3 of the green ones, 1 red one.

Guess I should use my calibrated Fluke DVM (our work meters must be calibrated once a year) and compare it to the charger cell voltage reading.
I also have a couple "volt checkers" (not sure the brand), I will compare those as well.

[Meatwad]

Using a craftsman dmm, which of course isn't calibrated so take this how you will. My thunder ac6's are never more than .05v off. The readings on the charger and my cheap cell checker are off though and read close to perfect. Been awhile since I checked, seeing this thread makes me wanna check again...

[stanmondz]

the charger and volt checker are both off, i use my meter at work, though i dont have to have it calibrated, i still trust it over the other 2 readings.

i wouldnt sweet it if your not having any battery/power problems, just sharing a problem and what i think caused it, and what i think the solution to my problem is.
we're playin trucks this weekend, guess ill know then if i saved my packs

my volt checker is one of the high end 3 dollar ebay ones, i guess the fact that the display still works after a couple years in something to be proud of

[Kingmeow]

Originally Posted by Johnnysplits

...even if I ever get that 600 class heli that I've been eyeballing ...

C'mon Johnny, you know you want one.... I'll even help you to find a good one. LOL!

[Johnnysplits]

Originally Posted by stanmondz

what charger you runnin Johnnysplits?

Cellpro Powerlab 6, 24v 1150w 47A power supply, Efuel fused power distribution box. I connect up to my laptop, hook up batteries and enjoy the show. The absolute best system I've ever owned.

[Johnnysplits]

Originally Posted by Kingmeow

C'mon Johnny, you know you want one.... I'll even help you to find a good one. LOL!

Sure, let's see if I can wave a magic wand and pull $2000 out of my ass!!! If I can, hook me up with a heli!!

[Trubble]

Originally Posted by Johnnysplits

Cellpro Powerlab 6, 24v 1150w 47A power supply, Efuel fused power distribution box. I connect up to my laptop, hook up batteries and enjoy the show. The absolute best system I've ever owned.

Are these still available? I was kinda looking at the MaxAmps version of this box and a Hyperion 730i charger. *sigh*









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