Voltage Reducer 36v to 12v

[CharlieH]

Hi, Trying help out a buddy of mine with a 36v Ezgo.Last week he called me and said on a full charge his radio would quit after 20 minutes and his cart was slower.I asked did he have them hard wired to 2 batteries and he said yes for the past 6 months.I suspected those two batteries and tried to explain the damage that CAN occur to the batteries without a 36v to 12v converter especially with extended use and no rotation,long story short he finially found out he did indeed have two bad batteries,the company replaced those two under warranty after testing all six , so I suggested he purchase a converter to draw off the set as a whole and he agreed.He has a 50 watt JVC stereo 50W=4.16A but he also has two headlights which he states is factory EZ-GO and I have no idea of the wattage,plus he has two small LED tail lights.I have not seen his carts headlights but as a ballpark guess,would a 16 amp converter be sufficient to run his accessories? Any suggested websites who sell quality converters at fair prices? I seen some on Ebay at cheap prices but they are generic,kinda hate to lead the guy toward a cheapo converter that may not last long

[Gale Hawkins]

I think 16 amp would be fine. Someone posted their head/tail light draw was 4 amp. In trying to learn how they work I saw one that seemed OK for about
$150. They are a neat device that I knew nothing about.

Check out everything. Another one posted he had his head/tail lights across two batterys for the past 10 years without any battery issues but I expect the lights were only on when the cart was in use so they will equalize.

Maybe he plays the radio for hours with the cart parked and not charging. When the cart is in use or on the charger I do not see a problem because all six batteries are functioning as one from my understanding so the amps pulled by picking off 12 volts will be replaced by the others when the 12 volt is present.

[CharlieH]

If not mistaken he has his lights wired to 2 other batteries which he mentioned that he only used the lights 4 or 5 times in 5 months but only for short periods and those two batteries checked out perfect.As far as his radio,it is on any time he rides and yes it is possible he plays it just setting around his shop.I have my lights wired to 2 batteries for the past 4 years and never had a issue but like the guy you mentioned, I use them very little and have rotated them to other batteries without any harm

[Gale Hawkins]

I have never read any research that proved taping off 12 volts for head lights and other low power 12v devices. I read where one converter maker stated it could void your battery coverage if you did not buy a device like they sold.

I need access to all 300 amp @ 12 volt that my batteries can give me.

Why do people pay $100+ for a 16 amp 36v to 12v converter instead of just doing it with light cables for a few bucks to get 12 volts from all six batteries at the same time?

I designed a converter with cables "only" on paper this morning to power our new 2000/4000 watt inverter from the cart battery bank. I plan place the 12v/315 amp output out the opposite side of the 36v/105 amp output.

[CharlieH]

If I'm following you on this,you are saying running all 3 of the 12v (pairs) into one 12v output correct?

[Gale Hawkins]

Originally Posted by CharlieH

If I'm following you on this,you are saying running all 3 of the 12v (pairs) into one 12v output correct?

Yes.

Does anyone have a link to a photo using three 12v chargers to charge a 36v bank of golf cart batteries?

These connection points would be the same to get your balanced 12 volt output but not voltage converter will be required.

You wire the batteries in series and parallel at the same time just like you do in a way when using three 12v chargers. You do not remove the series cables to use three chargers per scottyb.

The place where I purchased just pulled 12v off two batteries for he head lights. One could do the same across two others for a radio then across two others for a 12v outlet to charge the cell phone on the course. Tie the three - cables to electrically be ONE and repeat with the + cables for balanced 12 volts from all six batteries. I will not look as cool but there is no convert/reducer to buy.

[CharlieH]

Well said and sounds pretty easy plus way cheaper.Thanks

[Gale Hawkins]

Originally Posted by CharlieH

Well said and sounds pretty easy plus way cheaper.Thanks

24 hours later I still am looking for the cons in an electrical sense of doing this to get a balance load on all batteries for 12v loads and have not found any yet. That is not to say I have not found people (on RV and tractor forums) who said it can not be done but none have supported their opinions.

It seems many are like me in finding working with DC storage batteries there are more offering advice than have experience.

My cart came with two batteries with missing posts so I may be drilling and tapping holes for cables like those who have worked on it before I got it.

If carts around the world were not already using series/parallel outputs at the same time for many years I would not be planning to install the 12 to 120 volt 2000/4000 watt inverter this spring.

It is snowing like crazy today.

[scottyb]

Is THIS what we are talking about ?
Has anybody tried it yet to see what happens? You get 36v test it with a meter not your radio ... the problem is that the batteries are connected in series via the battery cables so even though you can grab 12v off of one poor soon to be doomed pair, when you grab 3 12v sources and connect them together the negative from the first 12v source and the positive from the last 12v source = 36v .... I hope this helps. Keep the brain teasers coming.

[dougmcp]

Originally Posted by Gale Hawkins

24 hours later I still am looking for the cons in an electrical sense of doing this to get a balance load on all batteries for 12v loads and have not found any yet. That is not to say I have not found people (on RV and tractor forums) who said it can not be done but none have supported their opinions.

It seems many are like me in finding working with DC storage batteries there are more offering advice than have experience.

My cart came with two batteries with missing posts so I may be drilling and tapping holes for cables like those who have worked on it before I got it.

If carts around the world were not already using series/parallel outputs at the same time for many years I would not be planning to install the 12 to 120 volt 2000/4000 watt inverter this spring.

It is snowing like crazy today.

I posted this in another area but will repost here:
You could only use 2 batteries on a 36v pack for an inverter, a series parallel connection will not work on a golf cart (a series/parallel hook up would leave you with the 12v power to operate an inverter but 24v short of operating the golf cart).
What are you planning to operate with an inverter?
IMO, a large inverter should not be run from the cart bank, you need separate batteries.
Not to say it won't work but a 2000 watt inverter will kill 2x6v batteries in 30 minutes running something like a 1200w coffeemaker. Recharging after using the inverter would overcharge the other 4 batteries in the pack so bad it would probably ruin them.