Use this method to properly charge your batteries when using a charger that is equipped with a timer. Get maxiumum runtime without overcharging and damaging your packs.

Here's How:

Hook up your charger to the wall outlet or your 12 volt power supply as required.
Attach your battery pack to the charger in the normal way.
Feel the temperature of the battery pack, it should be at room temperature.
Start charging the pack using the normal method for your charger.
Every 5 minutes or less, feel the temperature of the battery pack.
If the pack temperature is the same as before, keep charging.
If the timer expires, start the charging process again.
You should now check the temperature of the battery pack every couple of minutes. Once the packs starts to get warm, turn off the charger.
Unhook the battery from the charger, install the battery in your car or truck and have fun.

Tips:

Never allow your battery to over charge. It should only get slightly warm when charging. Overcharging your battery can cause it to explose and may cause bodily injury.
Always let your battery pack cool down to room temperature before charging it again. Failure to do so may decrease performance and cause premature failure of the battery pack.

HANK YOU SAY CHARGE your batteries should be warm not hot ok so how warm is warm I have an mrc 989 with a temp probe and right now I have it set for temp cut off at 100 degres is this to hot or could i go higher ? batterier have not got this hot yet and seem to receive afull charge

HANK YOU SAY CHARGE your batteries should be warm not hot ok so how warm is warm I have an mrc 989 with a temp probe and right now I have it set for temp cut off at 100 degres is this to hot or could i go higher ? batterier have not got this hot yet and seem to receive afull charge

grunt66,
Hank has outlined a charging method using a TIMED charger. Your 989 does not offer a timed charge unless i'm mistaken. The battery temp has a lot to do with the ampere charge rate and how fast the battery is being charged. Your charger is more than likely shutting off on the Delta peak long before the temp probe comes into play, unless you have changed your charge parameters. The hand battery pack temp monitor thing is a learned thing after charging several packs you will get the feel of it or you'll pop some packs.

What battery are you charging and by what method?

I am a old guy like Hank and I still touch my battery packs during a charge cycle. I'm looking for heat rise in the pack.
Old Habits are hard to break. Heck back in the day we would get our Nicads almost to the point of venting and then put em in the car. Now that is one hot pack.

When all else fails always READ & use you battery charger manual it will set you straight. If not Nicad & Nimh batterys will vent, Lipo's will melt and catch fire, sounds simple.

I'm chargeing 3800 nimh at 6 amps and like I told Hank I've got my temp cut off set at 100 degrees before I reset this Packs would go way over 130 like you and Hank i'm an old timer myself over 25 years and I can remember venting a few nicad packs myself but I thought Hank might have some information I did'nt have but thanks for your input