would this work for 12v memory on stereo?

[TahoeDawgZ71]

Originally Posted by bb93gt

Ok, I'm going to go with a 48 to 12v converter (25amp) to run my lights and stereo, and a extra battery for my memory. I found a 12v battery out of a emergency light for my memory on my stereo.
The only question I have is do I ground the extra 12v battery to the cart? (- to the cart frame and + to stereo memory) I've put in a bunch of stereo's in car's before, but the 48v system has got me a little confused.

You can't do that. Read my previous post. You can't feed the stereo from two sources

[bb93gt]

Thanks TahoeDawg, I understand what your saying. Screw the memory, I'm just going to hook it up to the switched 48-12 converter.

[TahoeDawgZ71]

Why not just use your converter to power the memory and the switched AcC wire? That's what I'd do

[roady89]

If you leave it sittin long enough you'll kill the pack too. Voltage convertors themselves use more power with no load than the memory circuit uses. That would be a mistake. You'll eventually drain the pack. One I just did a quick look at uses 10 watts with no load. They are all doing to be different specs but one thing they all do is use power to make the conversion.

[TahoeDawgZ71]

Roady is correct. That's why I use the tow/run switch to feed the control wire. If you're gonna leave it stored for a while put her in tow

[1BDPRECEDENT]

When I installed my converter everything requiring 12v to operate was moved over to it. It turns off with the key switch so I too was faced with the issue of losing 12v for radio memory with the key in the off position. To resolve this issue I used the existing blue wire coming from the positive terminal of battery #4 to power the memory wire to my radio. It has been been setup like this for well over a year and has worked flawlessly. I was concerned of the effect it may have on battery #4 over time but there has been none. All of the batteries are within .02v of each other. I usually have the cart on the charger about once a week, maybe if it sat for really long periods of time between charges it may have a chance to draw that battery down more than the others.

[simple man]

I have two questions about this. First, on a 48V to 12V converter, does the 12V output negative lead also connect to the b- of the battery pack or does it remain isolated from the battery pack? I believe all the 12V accessories are connected back to b-. The second question is why can't you use two sources for a radio? I hooked up a radio out in my shop and used a 12V battery to keep the memory and used a battery charger to power the radio. It worked fine until hurricane Frances drowned it!
I am not trying to argue with anyone about the radio, I'm just totally curious!

[TahoeDawgZ71]

Originally Posted by 1BDPRECEDENT

When I installed my converter everything requiring 12v to operate was moved over to it. It turns off with the key switch so I too was faced with the issue of losing 12v for radio memory with the key in the off position. To resolve this issue I used the existing blue wire coming from the positive terminal of battery #4 to power the memory wire to my radio. It has been been setup like this for well over a year and has worked flawlessly. I was concerned of the effect it may have on battery #4 over time but there has been none. All of the batteries are within .02v of each other. I usually have the cart on the charger about once a week, maybe if it sat for really long periods of time between charges it may have a chance to draw that battery down more than the others.

That's fine because you're sharing a common ground. But I'd definitely keep an eye on the battery pack.

[TahoeDawgZ71]

Originally Posted by simple man

I have two questions about this. First, on a 48V to 12V converter, does the 12V output negative lead also connect to the b- of the battery pack or does it remain isolated from the battery pack? I believe all the 12V accessories are connected back to b-. The second question is why can't you use two sources for a radio? I hooked up a radio out in my shop and used a 12V battery to keep the memory and used a battery charger to power the radio. It worked fine until hurricane Frances drowned it!
I am not trying to argue with anyone about the radio, I'm just totally curious!

No, the 12V output lead attaches usually to an isolated ground block totally separate from anything else on the cart. As for the two source question... The car stereo is setup for 12Volts, we both agree on that. You may wire two batteries in parallel and use two sources to power it that way. But why would you want to do that? You're forcing your charger to charge 5 8 volt batteries with 4 cells a piece, and one 8 volt battery with 8 cells in a sense. It's not the thing to do. Internally, a Car CD player is setup with 2 positive feeds, and one common ground. They're designed to all operate from the same source, a 12 Volt battery. If you were to power the radio with two sources, how were you planning on hooking it up? You've only got one negative wire, you can't hook it to two batteries without wiring them in a parallel circuit.

[TahoeDawgZ71]

After re-reading my post from last night this theory makes even less sense.... The two batteries in parallel would have to be an 8-Volt and a 12-volt battery. A definite no-no especially in a parallel design. The charger would have serious problems keeping up with that.