rdnbrbk

iTrader: (31)

I would like to know what unit of measurement is used for the Resistance ratings on the labels of the individual cells? For example one of the labels on one of the cells of my pack says it has AR 2.0. What does "AR" actually mean and is it measured in Ohms or miliOhms?? Thanks a bunch.

jamescam

iTrader: (10)

The only downside with the Reactor is that it discharges as a pack not individual cells but so does the Turbo 35bl or GFX, plus as you point out you use a tray to equalize the cells before you charge them up so you are covered. Great battery routine.

M LANE

The "AR" is a term used by Competition Electronics which is the company that makes Turbo 35 chargers and the matching equipment used by the battery companies. When you use there T35 to cycle a pack it gives you a AR and AIR reading for internal resistance. The AR is actual restistance, and I believe it's in Ohms. I'll have to varify in my manual it's been along time since I've read through it, but I'm pretty sure it's Ohms.

M LANE

A battery routine doesn't need to be complicated with 3800's. As I said before don't worry about the trick of the week.
Nilsen gave a good example of a battery routine. Don't get hung up on what type of discharger you use to get to 5.4V it can be a charger, bulbs, or whatever. Run the pack, discharge it, and equalize before you use it again and you won't have any problems. Remeber there are alot of companies who make a leaving on selling the next big thing in battery maintenance. Look at how many different types of dischargers Integy has on their website! Keep it simple and practice practice practice!

jamescam

iTrader: (10)

That maybe over simplifying it. First, bulb dischargers don't usually stop at 5.4v. Second, discharge rate does seem to have an effect on long term performance of batteries. While nothing beats practice in terms of overall performance, battery management is right at the top along with motors maintenance and tire selection.

rdnbrbk

iTrader: (31)

Thanks for the quick response. If you find it in your manual, let me know for sure. Thanks again though.

M LANE

I've learned that when you get to technical people want to dispute things. Anything I post is from my own experience and testing. Bulbs will cutoff at 5.4V if you install the optional cutoff. In regards to recommended discharge rates they are like belly buttons everybody has one. If you get technical about it some dischargers don't exactly do what you would expect in regards to constant discharge rates etc. or what is claimed. I have not seen any long term effects on 3300's when discharged at various rates 10-30amp. I have gone as far as to take 12 brand new packs at the same time and charge and discharge in several ways including dead shorting to determine the effects. 3800's are a different story. If heat is as bad for 3800's long term as many people state then discarging at a 10-20 amp rate is probally going to be safest. They get really warm at 30 amps, but are far cooler at 20. Racers including myself get to wrapped up in the battery games. I've learned the hard way simple is best and there is no magic in batteries. Buy the best you can, and don't worry about it. There's always somebody with better cells! Use a consistent routine and you will be fine.

John Malin

AIR is actual internal resistance and is measured in milliohms

Hows it going mark?? long time no chat....


John

DennisNyholm

iTrader: (7)

Well, i've noticed that when I discharge with my ICE charger, it gives resistance (of the whole pack). I usually get a 53 milli ohm resistance value. On the cells I have anywhere from 1.9-2.0 based on a CE35 turbomatcher rating. I wonder how the two of them relate to each other??

John Malin

according to ohms law 53 milliohms yields a pack theoretically capable of 135 amps at 7.2 vdc. put a current meter capable of 200 amps dc inline with a short on your cells and see how much they can deliver. theory says you should be able to determine the resistance from the current with known reference voltage..e/i=r please dont try this at home as it is dangerous. The safer way to do it is to put two very stable known loads on your pack and then measure the voltage drop difference between the two. since you will know what the current is and you will know what the voltage drop was then you can deduce the internal resistance plus the external resistance(quality of build) if you do this on individual cells and then repeat the process on assembled packs you can find out how good you soldering job is and how much resistance it added to a pack. I think some people would be surprised at how bad a good looking solder joint really is resistance wise. this is why most cell labels wont ever match the turbo numbers when yoou cycle new packs. Funny business aside.

John

TripleX-JT

iTrader: (1)

Good luck to everyone attending the Birds

M LANE

Hi John,
It's been way to long, but I'm glad to see you still post now and then. I hope everything is going well with you.
Aaron has run alot of T/C for the last 2 months, and did really well. Stock wasn't much of a challenge so he moved to 19T after about a week. Even then after a couple of weeks he was in there with the factory drivers.
We just changed gears and went back to offroad last week to get ready for the Cactus. He is entered in both 19T classes and should do well.
Checkpoint has begun production on the 19T ( not shipped yet) and we have high hopes for it. It has out performed all of our other 19's hands down.
The 3800's are awesome and we couldn't be happier with our batteries.
Don't be such a stranger hope to talked to youn soon.
Mark

M LANE

Aaron and I would like to say good luck to all the Fusion drivers attending the Snowbirds.

BeetleBailey

I have to just say thank you to fusion! I still have 3300's that stil charge to 3585mah and 9.545 volts. Thanks for some serious bats.

Red Z

iTrader: (25)

John....

...dun dun...

...dun dun...

...dun dun...dun dun...(the tune of Jaws)

I'm comin' back!