wiring 12v lights to 36v EZGO system

Originally Posted by yurtle

He was wanting to use an aux battery, but was hoping there was a better way to charge it than using two chargers.

I've pondered this, and the only way to really do that is to have a converter to charge the aux battery, while charging the pack. The converter would have to have additional circuitry to properly charge the aux battery AND it would have to withstand the highest voltages during the end of a charge cycle. AND, you'd have a converter, so you wouldn't need the aux battery.

AND ... if it was possible it would of been done already !!!!

12 volts is 12volts as 36volts is 36volts ..
a 36v charger puts out 44.5v at shut off of a 36v cart and batteries settles to 38.27v or 6.38 v per battery .. based on my cart 6x6v batteries
so you put 38.27 into a pack of 6 6v batteries and 1 12v battery you get 4.78v per 6v battery and 9.56v in the 12v battery not a good way for you to have your batteries ... even if you recharge the pack the 12v battery will not achieve a full charge
batteries don't know when they are full.. its the charger that is in control and senses the pack voltage and shuts off

[Knothead]

Originally Posted by crash test dummy

AND ... if it was possible it would of been done already !!!!

12 volts is 12volts as 36volts is 36volts ..
a 36v charger puts out 44.5v at shut off of a 36v cart and batteries settles to 38.27v or 6.38 v per battery .. based on my cart 6x6v batteries
so you put 38.27 into a pack of 6 6v batteries and 1 12v battery you get 4.78v per 6v battery and 9.56v in the 12v battery not a good way for you to have your batteries ... even if you recharge the pack the 12v battery will not achieve a full charge
batteries don't know when they are full.. its the charger that is in control and senses the pack voltage and shuts off

Crash....this subject is starting to give me a headache! LOL!

I think we all agree that this won't work correctly, but it seems to me that you are convinced that he's talking about adding 12 volts IN SERIES with the pack to create 48 volts. That's not what he's talking about. He's talking about hooking it IN PARALLEL with two of the 6v batts (2x6 =12). The aux batt would be receiving 12v from the two 6v in series, so in theory it would work, just would create an imbalance due to the different amp/hour rating of the two 6v created by paralleling the 12v batt to them.

Yurtle is on the right track.....if you alternated the two 6v batts you used each time you charged the pack, it would probably "work" OK.

I have actually tested this method with some smaller sealed-lead acid batteries, using two 6v batts in series, with a 12v batt hooked to them in parallel. I charged them by hooking the leads of my charger (set at 12 volts) to the two 6v batts in series. After charging, the 6v batts had 6.35 volts & the 12v batt had 12.7 volts. The only thing different about my test is that the 6v batts are almost exactly half the amp/hour rating of the 12v batt, so my a/h ratings aren't as skewed as they would be when connecting a small, low amp/hour 12v batt to two, high amp/hour 6v's in a 36v cart pack. This is where the amount of charge that the "oddball" connected batteries would be affected the most.

I ain't arguing "for" or "against", & am finished with this discussion. I still say, "Don't do it!"......

lmao !!! i had a headache before but felt bad for being short with my answer

no i figured it as parallel for him .. remember the batteries will equalize to the lowest battery and bring it up to where every battery is the same .. what he is thinking is when you jump a 12v battery with a car you really use the alternator to charge the battery .. the 12 aux battery will receive the same charge that the 12v (2x6v) receives but charger will see that as volts not as the batteries them selfs and shut off when it reaches max volts but all batteries will be under charged

if it was in series then you would still not fully charge the batteries with out a 48v charger .. best to just buy a 12v charger and forget about hooking up to the 36v pack to charge

ok i'm done tooo !!

[cgtech]

JEEZ, get a voltage reducer. dpi sells american made ones for around 150.

[yurtle]

Originally Posted by crash test dummy

AND ... if it was possible it would of been done already !!!!

Sorry to have caused any headaches.

I'll bet more than one member has done something that's "never been done before".

A recent "brainstorming" session resulted in a PowerWise mod that's cheap (free for us pack-rats) that would help folks who leave their buggy unattended for months.

Questions are good, and sometimes when we say "don't do it", folks question "why". Everyone has differing levels of electrical and mechanical experience, and some may need more 'splainin' than others. I know I've asked my fair share of "why".

We've also experienced some hard-headed folks who refused to listen to "reason". In this case, the "hijacker" has only posted 7 times, so we don't know.

[ab46501]

I went the converter route because for me it was the simplest solution. There is nothing wrong with an aux battery either.

I just did not want the hassle of keeping up with a second battery to charge. I figured the one time I really needed my lights to work I would have forgot to charge the extra battery.

I was not knocking the OP for his thought at all.