warning on my 306B

[renefigueroa]

I have had my 306B almost two years. Recently it has started giving me the following warning after an extended charge it says " safety time over breakdown". I charge the gamut from 5000 mAh 6C batteries to the little micros. lately the 5000's have gotten most of the attention. I have made no changes to the charger settings, and normally charge at 1C. It properly charges the batteries, as many as 4-6 at a time, but it appears not to shut down until the safety cutoff. The manual says very little to guide me. Thanks

[rlclemmons]

There is a charging time limit, which you've exceeded. It is a programmable setting in the charger. There is a similar limit with regard to charge mah capacity limit which will show a similar error.

[renefigueroa]

Thanks. The charge mah is set at 30,000 so it is not the issue. Mt question is why is it doing this now? it was not doing so in the past, and the settings have not been changed. The batteries are showing fully charged, so what do I do? increase the safety time?

[RedOctobyr]

Do you have Trickle Charge enabled? I think it's part of the Balance options in Settings.

Let's assume the time limit is 120 minutes. Does your charge actually take 2 hours, or is the last hour it just sitting there at 0.1A or something?

As packs age, their internal resistance goes up. This could make them take longer to charge/balance, which could account for why you've only started getting this message recently. As they age, they also tend to get further out of balance, if one cell starts to go bad before the others, etc.

[renefigueroa]

Now that does make a lot of sense. I am quite sure the packs are long balanced and charged before the 120 minutes is up, so I am guessing it is sitting there idle, but not cutting off. I am certainly no electronics guy so pardon my ignorance, but I do seem to see it sitting at .80 on the meter, then goes down a bit to say .65 but then comes right back up to .80-85. And I will check for the trickle charge in the settings, not sure about that one, thanks.

[Slyster]

disable all safety timers.

[renefigueroa]

I disabled the trickle charge and initially charged one Turnigy 5000 at 1C. I manually cut the charger off after 1:55mins. The charger had been at .2A for 15-20 minutes. The cell readings were as follows from 1-6. 4.136, 4.153, 4.178, 4.191, 4.207
I have a second one charging at 2C right now to see if it will complete the charge. The first battery has only 36 cycles before this last charge.

[RedOctobyr]

With a spread of 4.136V to 4.207V, it sounds like you're fighting a cell-imbalance problem. One cell is already full, at 4.20V, and other are lagging far behind.

You might try going into Settings, there is a page for Balance. You can set it to start at CV (the default, waits until a cell reaches 4.2V to start balancing), Storage (starts at 3.85V), or Always.

I'd try Always. At least you'll get sort of a 20-minute (or whatever) headstart on balancing, which might save you some time.

That seems like a rather big voltage spread. It's possible the packs have gradually gotten way out-of-balance. You might intentionally do a slow charge (maybe 0.5C), one pack at a time, using Always for balance, with the Safety Timer disabled. Perhaps pulling all the cells back into balance once will help you in the future, if you're never actually fully-balancing them during a charge. Causing it to struggle to balance them every time, then eventually hitting the time limit, and giving up.

[renefigueroa]

Thank you, I have been balancing every time, perhaps not a good idea?I will try what you suggest. I just went back and just charged another pack at 2C. It was beeping and done in twenty minutes, so the charger is doing what it is supposed to. I was not aware that batteries would get so far out of whack by balancing every time.

[RedOctobyr]

No, sorry if I worded it poorly. Balance charging is good, and helps. Keep doing it that way.

The charger is doing its job, and you're not doing anything wrong. It sounds like maybe your pack has gotten out of balance somehow.

It IS possible that the charger is having a hardware problem with its balancer. But one thing at a time.

Sent using Tapatalk.

[renefigueroa]

Lol Ok I will change the settings and try the balancing very slowly and see if that makes the charger happy.

[renefigueroa]

Lol Ok I will change the settings and try the balancing very slowly and see if that makes the charger happy.

[Bimbo]

I actually had negative experience with turning balance "ON" to "ALWAYS". I have a pack in which one of the cells has lower IR than the rest. When the pack is at rest (no charge, no discharge) all the cells have the same voltage. When charging, the cell with lowest IR has lower voltage than the others, and the balancer is active. So that cell is getting more charge than the others. Then later, this cell has more charge than the others and when CV phase is approached, the process reverses: the cell that HAD the lowest voltage, now has most charge and the balancer needs to work in the opposite direction. It was taking my charger a long time to charge this pack.

Does this apply in all cases? No, but it's something to keep in mind. This particular pack charges a whole lot quicker when the balancer is only active in CV phase.

For the rest I agree that a slow charge may help - if it does, the above explanation does not apply to your specific battery . Check your IR's. If the IR of all cells are similar, I would think a slow charge can definitely help - with the balancer set to "ALWAYS".

Typically the charger will stop charging at 10% (I believe it was 10%...) of the set charge rate (so if set at 5A, it will stop charging when the current reaches 500 mA). If you charge faster (10A), the charger will cutoff earlier (1A). This will reduce the long taking balancing at the end of the charge and may reduce your charge time considerably.
Then again, if your pack is so far out of balance, it's probably because the pack is starting to fail, so you may wonder if you want to charge faster...

[renefigueroa]

I have one pack charging this morning set to "always" and at .5C lets see what it does

[renefigueroa]

Ok pack charged . I let it go for 3:10, ending charge at .02A. It said charged to 24.7 Volts total. Cells ended up as follows. 4.024, 4.100, 4.160, 4.143, 4.208, 4.071

[RedOctobyr]

Hmmm. It should be much closer than that, I'd say.

It's possible to have a hardware issue with the charger's balancer circuits. You can have a case where, for instance, the balancer for cell 5 can't bleed off as much current as it's supposed to.

In that scenario (I'm now speculating a bit), the charger is not allowed to let a cell go past 4.20V, so it has to limit the charge current so it doesn't add current faster than the balancer can remove it.

The balancer should be able to bleed off 0.5A. So the charger can charge the pack at 0.5A, and the balancer can keep removing that 0.5A from the high-voltage cell.

But let's say something's wrong, and it can now only bleed off 0.05A. Now the charger has to slow the overall charge down to 0.05A, to avoid letting the cell get beyond 4.20V. At that rate, the other cells will take a very, very long time to come up to 4.20V.

I'd start looking for patterns in packs. What are the per-cell voltages for each of your packs? If, say, cell 5 is always the high one, and the charger can't really resolve it, you may have a hardware problem.

With the 0.5A of charge current available, you shouldn't see that much imbalance after 3 hours, in my opinion/testing, unless you started with a *massive* imbalance. Do you have access to another charger, to see if it can balance the packs?

[renefigueroa]

I do actually, a small one from HH and my very early days, and I believe it does have 50W, so I should be able to charge one pack alone. Great idea, thanks. I will go plug one in

[renefigueroa]

I charged two packs separately. Firsr started at 23.37V cells at 3.874,3.886,3.903,3.905,3.926,3.878. after a charge of 1C and the safety timer cut this one off at 3:00 and cells read 4.18,4.18,4.17,4.20,4.18,4.17

second pack started at 23.39V and 3.883,3.891,3.901,3.90,3.917,3.904. I let it charge for 1:30 and maybe should have let it run as well. readings were 4.201,4.202,4.196,4.198,4.203,4.203

[renefigueroa]

And as an added question, I have never updated the charger. I know you can do this but would it make a difference in the charging?

[RedOctobyr]

The first pack is pretty good. I'd let it finish charging, if it were me. The second pack is very good. But in both cases, letting it finish charging will help get things properly balanced, which will only help you.

Unfortunately, I doubt updating the firmware would do anything. You could try it, of course.

You're out of warranty, unless you used a credit card that doubles warranties.

Even if you didn't buy it there, I'd contact ProgressiveRC.com. They have a service where they'll repair/replace out-of-warranty iChargers, for much less than the cost of a new one. It would be worth finding out what they might be able to do for you.