disaster999

iTrader: (1)

i bought a gmvis commander off someone and they told me that its perfectly safe to charge nimh at more than 2C when using pulse charge mode. but people are telling me that if i charge at more than 2C, i would cook my cells. now im really confused. the guy who sold me the charger is somesort of sponcered racer. i really dunno who to believe. please help

429racer

iTrader: (19)

I own one but I guess I don't know what you are talking about when you say charge more than 2c. You talking amps, temp cutoffor what?

disaster999

iTrader: (1)

sorry i mean when im charger more than 6 amps
the team driver who sold the charger to me said he charges at 8.8 amps for this cells at GMVIS mode.

429racer

iTrader: (19)

The Vis-charge function works best between 7 to 9 amps charge rate. If you do it this way then just watch the battery temp or run a 12 volt fan on the batteries, that will help. After charging just make sure you take the fan off the batteries as you don't want to cool them down. I always charge with peak charge or temp charge at 6 volts club racing, sometimes more if I want a little more punch. Temp cut-off should be set at about 42 degrees celcius if you use this method. The vis-charge is a function I used when I had a hard time putting charge back into my batteries after being dead shorted.

disaster999

iTrader: (1)

thanks
i thought your not suppose to put a fan on the cell when charging

429racer

iTrader: (19)

I think the biggest part is that you want to take it off just before it peaks, because if the batteries cool down you loose alot punch from the cells also not for cycling because it will give you inaccurate information. If temp charging you definately don't want to use a fan. For the temp charging you can use a regular like temp probe they use with multi-meters hooked up to the right input slot if you want to do it that way. You can just tape it to the batteries but just make sure the probe is covered from the ambient air.

Michal101

iTrader: (13)

If you use a fan while charging your batteries you run a very good chance of overcharging your cells which will give you decreased performance and longevity. None of the battery matchers recommend using a fan while charging...only during discharging.

Now, your question concerning the GM VIS commander. Which version of commander do you have? They basically have 2 models, one has one set of charging outputs and the other has 2 sets of charging outputs.

Also, what type of batteries are your using, Ni-cad or NiMH? If you are charging the NiMH then use the temp charging method, but I would not go over 6 amps for charging.

Do not use the GM VIS mode for re-peaking since it will force feed your battery pack until it thinks that it is done. When using the VIS mode for a complete charge keep the batteries connected since whenever you use the GM VIS mode it keeps the batteries warm for you until you disconnect them.

I hope this helps, Mike

disaster999

iTrader: (1)

thanks mike, i have the older version. the one with one set of charger leds. i mainly charge nimh with the charger.

what do you mean gmvis charge mode keeps the battery warm until the battery is removed from the charger? does it trickle charge after its done? or just keep feeding juice to it till i take it off?

thanks

Michal101

iTrader: (13)

Hi,

I am not sure how the commander keeps the batteries warm, whether by trickle (which I do not think so) or whatever, but it just does.

Basically, NiMH and Ni-cads for that matter, work better when they are warm so the commander keeps them warm while keeping the voltage higher until you disconnect the charging leads from your pack.

I always install the pack in my car and then I charge them and leave it connected until I hit the track for my run.

Mike

disaster999

iTrader: (1)

thanks mike

disaster999

iTrader: (1)

where is the function that could charge lithion batteries?

btw, the version charger i have is V1.04

disaster999

iTrader: (1)

anyone?

Tres

iTrader: (14)

I think the specs on Horizon are wrong.

http://horizon.hobbyshopnow.com/prod...?prod=GMM94401

It says "* A voltage peak mode terminates the charge when a preset voltage is achieved (used for lithium metal packs)"

Lithium metal???

I think it should be NiMH that uses peak detect??

disaster999

iTrader: (1)

no, that is right, the GM comander could charger lithium metal batteries! it would stop charging when a curtain voltage is met!
it uses delta peak for nicd and nimh!

disaster999

iTrader: (1)

any one got an answer on how to charge lithium metal or li-on batteries on the gmvis commander?