[scaleguy]

Originally Posted by ronm

well then, if they are the batteries that came from me, they were only used for 4 flights, no crashes.

Ron,

Yes they were the 1500 and Randy no they had not been in a crash.

I think I had the current up to high. When I checked this morning they wer at 1 Amp but may have been knocked. In a rush and didn't have my glasses on almost cost me a lot. As I said though I am going to sideline the other pack and the charger for now.

I was using a Hobbico Quick Field Charger Mk.II. It is a dual output charger, both seperately settable. I had one hooked up to each pack. The other pack actually beeped while I was stoped at Wendy's so I disconnected it. Leads were standard length about 24" so nothing there either.

Ron... this should put me up for the PrangedPig but at least I wasn't as bad as Don Brisson who forgot to fill the tank on his U-Can-Do 60 and then lets Darlene fly it only to have a deadstick and off fiield landing that ripped the gear out.

[Rick Kroeze]

Ouch Jim,

I charge mine on the way to the field all the time. (Always forget to plug the stupid thing in) This has got me re-thinking that as well.

[50%300SFlyer]

Jim,

Sounds like you charged them at too high a rate, or the peak detection did not work...

NiMH batteries should not be charged at any rate higher than 1C. In your case, the maximum would be 1.5 amps, with peak detection.

I had a look at the instructions for your charger on the web, and I see that it charges both NiMH and Nicads, but you have to select which batteries you are charging. [yellow or red light] Perhaps you may have selected the wrong one? The peak detection characteristics are different for NiMH and Nicads.

I run NiMH as well, but the chargers I use are from Sirius. They are all plug and play, and automatically determine the type of battery, and the # of cells. They also have peak detection, and then go to a trickle charge. Real hard to make a mistake.

http://www.siriuselectronics.com/ind...e6f30107d82ad2

Hope that helps!

[Rick Kroeze]

Mike,

Have the same charger. Do/would you charge unattended?

[50%300SFlyer]

Yes....I have used it in my vehicle overnight, and on the bench in the basement with a power supply. The only batteries I will not charge unattended, are Lithium.

Your mileage may vary...

[ronm]

Geez, they should be able to handle 1 amp. Must have missed the peak and kept charging until they overheated.
I think a temp probe may be a good investment when peak-charging.

[pherchris]

Hey Jim,

Glad to hear you, the plane and the van are ok! I'm using a 2000mAh NiMh on the ignition on the Yak and also use the Hobbico QFC mk2 from time to time (great charger) and the Hobbico Elite. When I charge this pack on the quick field charger, the pack stays fine up until the last 15 minutes or so of the charge; at that point it starts to get very warm and I keep a very close eye on it. The charge will usually peak before a dangerous temperature is attained. I normally charge this pack at about half an amp and it doesn't take any longer than an hour to one and a half for it to peak.

I guess the quickest suggestion would be to reduce your charge rate with these NiMh cells and keep a close eye.

BTW; When I charge with the Accucycle, I use the temp probe as ronm suggested and it works excellent! I highly recommend it.


Chris.

[ronm]

according to Red, charging on the NiCd setting could also cause this result!!

The Ni-MH that are available to us today from Sanyo/Panasonic may be treated essentially the same as Ni-Cds –EXCEPT FOR PEAK CHARGING. You have to be careful here. Some chargers will accommodate them, others won’t - and end up severely overcharging them to the point of destruction.

Easy to pick the wrong setting with that charger. (hmmm....did I push the button once, or twice???)

[scaleguy]

Yes I know that Nicad and Nimh have different peeks and I am about 99.9% sure I pushed the button twice. So at 1 Amp I should have been OK. It seems the kob for adjusting the current has come off the side of the charger that was attached to this battery. Looks like something may have overheated in the charger, don't know if that is cause or effect.

Chris and Ron I don't know of any place to hookup a thermal probe on this charger, it's not a Trition. I have the Accucyle Pro, not the Elite so there is no thermal link on that either.

I guess my first thing I buy next year at Toledo is a Sirius charger.

Well I am going to go home tonight and check everything over very carefully as I do not want to loose this bird, even if it is a Edge

[Frank Klenk]

That's pretty scary Jim. Glad you and the plane are alright though. I use the nimh batteries and always slow charge them, 50 mah. They are always cool to the touch when I unplug and they cycle down over 100%. I guess it's all about having a routine to follow. When I shift away from it that's when I make a mistake. GAWD, imagine if you were'nt there when it happened!
Lesson for me? All the more reason to be ---- as hell with batteries.