Charging help with IB4200s

[C_J_M]

I have the MRC 959 and just got my 7-cell 4200s in the mail. At what setting do I set the 959 to for the first charge?

[cooleocool]

If you mean charge rate, try 3.5-4 amps.

[C_J_M]

ON another forum someone posted something about charging for 15hrs for the first charge. IS there any truth in this?

And if I set it to 3.5-4 amps......what do I set the milivolts to? Also, whenever the charger fully charges it gives off 3 beeps, then goes to a trickle charging. Should I disconnect before the trickle charge or should the battereies be allright during trickle charge?

[BP-Revo]

The trickle charge just keeps your batteries at maximum voltage before you run them.

You can choose to leave them on, take them off, or run them right away.

Running them right away will give you the best performance, leaving them on for a bit would be the next best step. Taking them off wont change much, but you will lose some volts that racers really prize.

NiMH batteries lose charge over time, the trickle charge is just so it keeps the battery nice and full until you take it off.

[C_J_M]

what about milivolts?

And will it make a difference when I hook a 7-cell pack compared to the usual 6-cell I have been using?

[razer]

I recommend not messing with the settings at all. Just connect the pack & press the start button.

[rupert]

I like reading the manuals.

[niggle1987]

i would charge them at 4.2 amps for a trickle charge, or for a charge where you want the most run time. But after that you can charge the packs at over 5amps for the best top speeds. On stella models site it says

INTELLECT SC-4200
High drain Type
Ni-MH 7.2v 4200mAh Stick Pack with fitted plug.
Require charger capable of a least 5 Amp current charging.

[batjerk]

Ordinarily, doing just as razer states is a good idea.

You can charge the battery at whatever rate you want, but is a good idea not to go overboard with high amp rates. 1C is usually very good. For you, that would be a 4.2 rate. Hardly a "trickle" charge. Trickle charges are usually around 500 miliamps or so, seldom a whole amp and never a 4.2 amp rate, that is a "quick" or "fast" charge.

[TexasSP]

The 959 only goes up in .5 amp intervals from .5 to 4.5 amps. I charge mine at 4.5 with great result. As far as the millivolts, thee really is no reason to change them. Keep in mind though, that the 959 tends to overheat and distort on higher amp longer charges so keeping it cool is necessary. I installed a small CPU fan to mine but you can also just run a reglular fan over it while charging. Also, it is easy to tell when it gets overheated as the display will distort.

[crewcabguy]

i just got my ib4200 too and i was going to use my "dynamite prophet plus" to charge them, the box says that it will charge 7cell packs, at 4 amp rate, is there somthing better i should be using? i want the most out of these batteries, especially due to their cost. any suggestions. oh ya this is my first post, i've been reading and learning lots here, any advice is welcomed, my truck has only had a few runs on cheap epic3000mah packs, so i cant wait to try these better packs out

[batjerk]

Sure, there are better chargers out there, but the one you have is just fine. In fact, the slower charge rate will result in a slightly longer battery life in terms of charge/discharge cycles.

[mebemikey]

I thought you were not suppose to trickle charge NIMH batteries. Am I right about that?

[razer]

I thought you were not suppose to trickle charge NIMH batteries. Am I right about that?

Yes, in regard to the sub-C size cells we use in R/C, that's correct.

[C_J_M]

Well, I charged them at 4 amp. Now, I do have an averaged "U" shaped yard so I can't get up to top speed.....but man I can honestly say there is a big improvement in its quickness.
One thing I did notice was that I couldn't do a wheelie for 2-3 mins when I first put them in. All of a sudden after that I couldn't keep the front tires on the ground.
Does this seem normal? Do batteries take a while to get "going"?

[cooleocool]

The batteries will take a few cycles to "wake up."

[C_J_M]

Thanks. .

[BP-Revo]

C_J_M, if you dont have room in your back yard to reach stock top speed, consider gearing down and locking it in second or something.

After gearing down slightly, first will be too short for anything except maybe rock crawling, especially on 7 cells.

Locking it in second would allow you to remove the shift servo and some weight.

That combined with the higher gear ratio (lower gearing) would increase run time and efficiency.

Just a though, if you cant use the top speed, why not tone it down?

[HyperHat]

what about milivolts?

And will it make a difference when I hook a 7-cell pack compared to the usual 6-cell I have been using?

I use 6mV/cell (42 mV total for a 7 cell pack). As long as the charger accepts a per cell setting then it can be used for 6 or 7 cell packs without changing it. Some battery types like 5 mV/cell better, but my IB4200 definitely do better w/ 6 mV/cell.