Batteries in Series Adapter

[JThiessen]

I have a new 989 Superbrain, and currently a plethora of 3300 NiCd's. So I attempted to wire up an adapter to charge them in series. But it appears that I failed miserably. The charger doesnt show an error, but it certainly isnt charging the batt's.
Here is a photo of my adapter
[IMG][/IMG]

So what did I do wrong on it????

looks right to me.

[JThiessen]

How can good news sound so bad?!?!?!

So something else must be going on. I hooked both batts up to it, and it just shows it cycling (yes, I changed it to 12 cells), the time laspe counter runs, and it continuously rotates through a few deifferent status displays (I dont know it well enough yet to say what they are). None of the fans kick on at all. I left one set run on it for about 4 hours, and they are basically dead still. I unhooked the batts and adaptor, connected one battery (changed it to 6 cell) and voila! Power supply fan kicks on, the meter shows it actually charging, and everything normal.

BTW, on the setting for Cut off Voltage, what should I be using? It shows "USED" and 1C, 2C 3C for options. SHould it be showing that for NiCd batteries?

[Sammus]

have you taken a multimeter to it? making sure you have the expected voltage and polarity on the other end? If thats all fine and dandy then your connector aint the problem.

^^^^ Def do that, get a pair of pacs that have voltage, check them alone so you know what each has. Connect the with your adapter and the voltage should be the sum of what you just measured. I built one looks a lot like yours and checked it this way to verify it gave me the sum of the 2 pacs voltage before I tried using it.

Sounds like you may have one leg switched??

[JThiessen]

Update: I measured each battery at 8.14V, connected them to the adaptor, and measured 16.28. So that tells me the adaptor is good. I tried adjusting the settings on the charger again, and actually got an error on it!
So I sent an email to Enerland (MRC), hopefully they can tell me what settings to put in on to charge them both. I've also searched these forums, RC Universe, RCTech, and RC Groups for a "settings" overview for the 989, but found nothing.
The batteries I charged individually ran great - seemed to have more punch than with my old charger (Vision Peak). Had a hard time keeping the front wheels on the ground!

[JThiessen]

'Nuther update: Email from Enerland.

You cannot select 1c or 2c but that is a reading of what the last few charges were and what capacity they reached.

Make sure that you have NiMH selected if they are 3300 mAh. Check the voltage display when you have your battery packs connected to see if you have the correct voltage. Since you have 12 cells you shouldn't see less than 12 volts. If this is a harness that you have made yourself then I would go back and check the soldering. Since both packs charge on their own I would have to take a guess that something is wrong with the adapter. You have the correct number of cells entered.

When you are doing a discharge then set your cut off V to 1.00. This will bring the voltage down in the battery to the correct level. That may help in trying to charge.

John

Wonder why they say I need to set it on Nimh for 3300's? That basically flies in the face of logic, and should be stated in the manual (IMHO). All in all, not a very helpful response.

I have this same problem with my Hyperion 0606i. Putting a meter on the adapter I see 14.4 volts out of the two 7 cell packs. Each pack charges fine separately.

My thread over at NK.

http://www.nitrokillers.com/showthread.php?t=1277

Post any updates please. I'll do the same.

[JThiessen]

I did some measurement's tonight, and at first it looked as though I was trying to charge full batteries, as they measured 15.XX V. When I pressed charge, the V display initially read 15.XX V, it ran up to about 20.X V, then back down to 15.XX volts. It then beeps and gives "-1.44 Err".
I tried to discharge them, but it shows an empty cell in the display, and reads 0.0V, 0.00 mAh. It keeps cycling though, but the numbers dont change.

I sent another more detailed email to them tonight, hopefully they will give more help tomorrow. I have a feeling that they are going to make me purchase an adaptor before they will believe it could possibly be the charger.

[JThiessen]

Update:
A week ago, I ordered an adaptor from MaxAmps, just to either rule out the one I made, or confirm it as the culprit.
I hooked up a pair of gp3300's, set it on autocycle, and it appears to function correctly. They charged up to 15.84V.
I tried the same with my IB4200's, but I'm still having problems with them. I think the charger is acting correctly. They will only charge up to 9.8V. I may have one of the infamous bad IB cells. Anyone have any tips or tricks to try to resurect a bad one? I'm currently trying to auto cycle them a couple times to see if that may help.

So it appears that even though my adaptor provided measurements that seemed correct, something was impedeing the electron flow - exactly why I became a Mechanical Engineer, not a Sparky!!

[lincpimp]

I have a superbrain 989, and have made quite a few adapters to charge multiple packs. I even made on to charge 3 6 cell packs in series. I have overvolt errors every so often. I usually let it beep after I hit start, then hit start again and it will work properly.

[JThiessen]

What exactly is an over volt error, and what does it mean? Is that what my error code meant ("err -1.44V)?

BTW, my second autocycle on the IB's dropped them down to 7.05 volts. Appears they are dying