How to create a 12 volt system from a 24 volt system?

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Jimm391730
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Re: How to create a 12 volt system from a 24 volt system?

Post by Jimm391730 »

My 710 has two 12 volt batteries connected in series to give 12 + 12 = 24v. Each battery has 2 + and 2 - posts and only one of each is needed to wire the circuit. The other posts can be wired in parallel to create a second circuit with 12v and twice the amperage. :shock: Treat it with respect!
Well, yes and no. You can only wire the batteries in series, or in parallel, but you can't do both at the same time! You will let the smoke genie out! :oops: And you will not be happy afterwards! :cry: And you might be taking an unexpected trip to the hospital, or worse... :shock:
... use an equalizer (very expensive) between the two batteries in the 24v battery pack and then take power from one of the batteries ... However the max amps these can provide is about 60 amps so not enough to equalize the batteries when a winch is being used.
But you can use a winch with a 60A equalizer; while the equalizer can't keep up with the current that the winch can draw, it will help to recharge the lower (12V) battery over time when you are not running the winch. The secret is that the equalizer needs to have more capacity than the alternator so it can take more current from the upper battery than the alternator creates; this prevents overcharging the upper battery. The lower battery will get charged, eventually, and all will be well at that time. And if you go this route then you can power all your 12V devices from the lower battery, too. However, you must be very careful how it is wired with the battery switch and general operation -- 1) you need to disconnect the equalizer when not running or it will gradually drain the batteries. 2) if the battery switch is off, and (for example) you try to crank the engine, the system reverses the 12V polarity to all your 12V devices which can destroy them. It all depends on how the equalizer is switched. It has to have at least two leads (the ground and 12V connections) disconnected to prevent this, so it takes more than a "simple" switch.

There are a multitude of ways to use 12V accessories in a Pinz and most of the above suggestions are very good options. You get to choose what is best for you. Generally, the most common outcome of a poor choice is that you will be replacing batteries much more often than you expect, and you will have more chances to make a better choice in the future.

To recap: 1) get a 24V winch. 2) get a 24-12V converter for the low amperage draw 12V devices (radios, CBs, chargers, etc.). 3) Get a 24V to 12V trailer converter if you really have to pull a lot of 12V trailers often. There are other ways to skin this cat, but most of them have their own drawbacks, too.
Jim M.
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audiocontr
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Re: How to create a 12 volt system from a 24 volt system?

Post by audiocontr »

krick3tt wrote:I have heard of this. Where do you put it?
I have a tap off the batteries to run 12V stuff and a 24 to 12 converter to run some other things, like the Webasto and the radio.
I still have one of these. It blows up constantly. I gave up on it after the 3rd warranty
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Re: How to create a 12 volt system from a 24 volt system?

Post by krick3tt »

The equalizer is mostly for the ARB cooler. Mostly the cooler runs off the batteries while traveling and the aux battery while camped that is recharged off the solar panel on the roof.
I don't use the equalizer to run the winch...12V off the equalizer and 24V winch. The winch is run directly off the batteries.

Had the equalizer for five years and it has yet to blow up. Perhaps, so far, I am just lucky, who knows?

Since I nave been associated with this forum, I have discovered there are several ways to do things. That is one of the many benefits of this forum, and learning from all the fine experts here is a great benefit for me. I appreciate all the information provided here by folks with knowledge and experience.
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better take a closer look at the American Indian.---Henry Ford
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Re: How to create a 12 volt system from a 24 volt system?

Post by Jimm391730 »

The equalizer is mostly for the ARB cooler.
I was thinking that the ARB and Engel coolers were "similar" (using the same compressor). The Engel is happy with 12V or 24V, it just draws double the current at 12V (2.5A from 12V, 1.25A from 24V). As I have the Engel I've always run it from 24V and not had any problems in over 12 years. You might want to check to see that yours can also be run on 24V.
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Re: How to create a 12 volt system from a 24 volt system?

Post by audiocontr »

I spoke with the creator of the device. He explained that several issues have been found with aggressive current draw on engine starts. Many folks have to use a relay system which cuts the unit out of the circuit when starting the truck. I gave up.
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Re: How to create a 12 volt system from a 24 volt system?

Post by edzz »

audiocontr wrote:I spoke with the creator of the device. He explained that several issues have been found with aggressive current draw on engine starts. Many folks have to use a relay system which cuts the unit out of the circuit when starting the truck. I gave up.
What device / unit?
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Re: How to create a 12 volt system from a 24 volt system?

Post by krick3tt »

When I said..'The equalizer is mostly for the ARB cooler'... I meant while parked at camp.
When traveling, I run it off the batteries (24V) as there is less current draw and the batteries are constantly being charged by the devices run by the engine. I have a special plug for each 12V and 24V use. If at camp for longer periods I run it off the aux battery as it is 12V and recharged by the solar panel.
While traveling, as I am only going to be stopping over night, I leave it plugged into the 24V outlet as there is no appreciable draw on the batteries of the vehicle for that 6 to 8 hours that would keep me from starting the vehicle, even when the temps are low.
I know there may be flaws in my thinking about current draw but I have had no issues in over 6 years of operation and I get new batteries for the pinz every two years. Whether I need them or not. It's just insurance and for my peace of mind.
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Re: How to create a 12 volt system from a 24 volt system?

Post by audiocontr »

The equalizer pictured on page 1
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Re: How to create a 12 volt system from a 24 volt system?

Post by compunerdy »

I bought and used the same equalizer.. a few days later both my batteries where dead.. unhooked it and charged them up and never had a issue since so either something got left on or the equalizer sucks (literally). One of these days I might hook it back up and see what happens.
Tim
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Re: How to create a 12 volt system from a 24 volt system?

Post by krick3tt »

Did you install it so the cut off switch disabled it when the vehicle was off? Makes a difference. If it is not connected to anything it cannot draw power and can't drain the batteries.
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Re: How to create a 12 volt system from a 24 volt system?

Post by Garrycol »

krick3tt wrote:The equalizer is mostly for the ARB cooler.
Sorry I am a little confused - when you say equalizer do you in fact mean a 24v to 12v converter??

Or do you mean the device that goes between the two 12v batteries in the 24v battery system and allows you to tap off one of the 12v batteries to get 12v power - normally this will kill the batteries but the "equalizer" transfers power from one 12v battery to the one that is supplying 12v power so that both 12v batteries maintain the same level of charge - if one 12v battery has a much higher charge than the other one in a 24v system they die.

A voltage converter and an equalizer perform completely different functions. Sorry if I have misunderstood.

Garry
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Re: How to create a 12 volt system from a 24 volt system?

Post by krick3tt »

I have both. An equalizer and a 24 to 12 converter, they are used for separate functions. I poster a pic of the equalizer but not the converter. The converter was installed by the shop that installed my Webasto heater as there were no 24V Webasto heaters available when it was installed. I have also installed a switch to remove the converter from the system to avoid unnecessary drain on the batteries, as a converter will continue to draw even when not operating.
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Re: How to create a 12 volt system from a 24 volt system?

Post by Garrycol »

krick3tt wrote:I have both.
Thanks
1973 Haflinger AP700
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Re: How to create a 12 volt system from a 24 volt system?

Post by audiocontr »

I'll sell mine for a reasonable price. Find out what it costs to have it overhauled by the manufacturer and we will work out a deal.
1973 712m
1968 Haflinger
1965 Pathfinder
1978 GMC Palm Beach (Hey, its got 6 wheels!!)
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