Bulb Discharger Dilemma

eVaDeR85 · #1 01-02-2005, 04:30 AM

I wanted to cycle my batteries so I broke down and went and bought 10 no. 1157 bulbs. Now I followed all instructions that ive read over various articles and I used all 10 bulbs but I have a question and a problem. The question is, since these bulbs are dual element, does anyone know exactly how many amps they pull each? Now my problem is, im not really sure if the dual element bulbs only pull 2 amp because when I put my battery on the discharger it wasnt on their for a minute and it was so hot that I literally couldnt touch it and the bulbs were still glowing bright so I just disconnected it in fear of messing up my battery pack. Is this normal? Its a rather old pack, nearly 2 years old. Its an old Dynamite Sport 1700Mah pack. I was just wondering if my pack might be having some problems or if these bulbs pull more than 2 amps each. Also when I had it hooked up, I used 12 gauge wire to assemble the discharger and even after a minute it started to heat up the big 12 guage wire I was using which lead me to beleive it was more than 20 amps of current. Anyway, anyone have any thoughts on this?

darncars · #2 01-02-2005, 06:08 AM

Ive been there buddy.1157s have 2 elements drawing 4 amps.1156s got 1 at 2 amps.(printed on side of bulb you know).I know everywhere you read says use 1157s thats the wrong number!After I figured that out I simpley cut the
string in half then got 2 more compact dischargers.

GotCoffee · #3 01-02-2005, 01:16 PM

How about putting half the string in series to cut down the current.

henry_huckem · #4 01-02-2005, 05:43 PM

Quote:

Originally Posted by GotCoffee

How about putting half the string in series to cut down the current.

yup, thats how you're supposed to do it, run a connection between the two side contacts of the last bulbs. that should fix it up, I have been using my 10-bulb 1157 d/c for about 2 months and am getting excellent charging results on all my packs.

raptorridr660r · #5 01-02-2005, 08:19 PM

I always thought the 1157 being 2 element would draw 4 amps, but I measured with a voltmeter, it draws 2 amps when both are lit, not 4, try it for your self, you have to break the circuit to measure current....

Grant Tokumi · #6 01-02-2005, 10:25 PM

FWIW, I also have a 10 bulb discharger, but I use 10 cell packs instead of 6. At 10 cells, they average around 26 amps discharge. So 6 cell would be less than 26 amps. I have an whatt meter that monitors the amps, voltage, and mah during the discharge.

eVaDeR85 · #7 01-02-2005, 11:51 PM

Well im happy to say that now my discharger works fine and my battery pack just gets really warm as its about to completely dump. Does anyone have any tips on how I can lower the IR of my cells through a charge/discharge cyle method or any other method that you can let me know of. I would like to get the most punch out of my packs. My charger is an original Dynamite Vision peak plus that ive done a few modifications to to help it charge better. Ive added a cooling fan, and ive upgraded all the main wiring to at least 14 guage. It charges at 3 amps on the 2 amp setting and about 5.9-6.2 amps on the 4 amp setting using my dads amprobe to measure it. It wont measure the DC current itself but it will measure the charger current since its a pulse charger.

eVaDeR85 · #8 01-02-2005, 11:55 PM

Oh and another thing. I took apart an old cordless drill battery pack that had 13 1500mah SC cells in them and I would like to assemble them for me to use. I dont have any battery bars so is there anything else I could possibly use instead of battery bars such as maybe a really this multistranded wire like say 12 guage thats been cut to the right length and then twsted to maybe look something like this >*<. (not the best thing in the world but maybe you get the idea. The asterik is the twist and the two ends are the seperate wires frayed out in like a fan to provide the greatest possible contact surface). That was just a thought I had though.

highroller · #9 01-03-2005, 06:34 PM

The auto taillight bulbs are rated at approx 2 amps but it's not a consistant 2amps for the full discharge but still what many of us have used for a discharger. I built several bulb dischargers based on what the pack is used for for oval racing 15 bulbs (30amps) offroad/TC 12 (24amps) bashing or unmatched cells 5 bulbs (10amps).
Most matched cells should be able to withstand higher loads of discharge while stick packs and unmatched cells may encounter problems. I ran in to that problem when trying to discharge some 1200RC (red shrink) using 10bulbs, many of them would start to vent, or I noticed they began to leak and even the shrink on some started to melt. So those were discharge with 5 bulbs and no problems until the cells started going bad. Now I use the 10amp on stick packs or packs no longer used for racing.