24 to 12 volt

[M725]

Do it as a CUCV, it has a 24 starter and radios. The rest is 12v.

 

[Beerslayer]

Really? There isn't a resistor in the circuit for low speed fan?

Really. It is a very lame setup. There is one stupid wire that goes directly from the heater fan switch to a center tap on the batteries so it gets 12vdc. I found out about it when I installed the battery relocation kit.

I considered just leaving it unhooked as I don't need a low speed heater fan anyway, but ended up terminating it and just not using it.

I like your idea better.

 

[59apache]

what about something like this?

NEW waterproof DC/DC Converter Regulator 24V (12-40V) Step down to 12V 60W 5A | eBay

i don't know the wattage from the fan, but i guess it's enough.
you an mount it close to the switch (instead a resistor)

 

[bigbird1]

ok guys, tell me why you can't run a hot to both battery's pos side and a ground to both battery's neg side ? that gets you 12v . Someone smarter than me tell why it won't draw the same from both battery's ?

 

[PsycoBob]

You get a fire, or a small arc welder. Since the batteries are still connected as a 24v pack, with a large cable from battery A's pos terminal to battery B's neg terminal, running wires from A's pos to B's pos will short battery B. Just like dropping a wrench across the battery.

If you want to do this, put a fuse in the wire first, right at the end, next to a terminal. It'll blow in a heartbeat, but a bulk pack of 15a fuses is cheap & you'll use them & the holders later anyway.

For a low-current load like a GPS, I use a sealed battery from a scooter with a fused lighter socket from Autozone. For radios, a 12v alternator will be a lot better. You can fit 3 group-27 deep-cycle/starting boat batteries in a plastic M35A2 battery box, not sure about the metal ones. That'd let you run 24v & 12v without worrying about destroying batteries. Most dedicated battery stores will sell 'seconds' with cracked carry handles or brackets for a big discount.


Wiring tip- buy a crimper & a bunch of those little waterproof fuse holders with wires on them from your favorite parts store. Put a ring terminal on one end of the fuse holder & a butt splice on the other- run your wire from that side. Attach the ring terminal to the battery +Pos connector, or the +Pos bus bar, if you have one. If you make a mistake or the wire chafes & shorts, all you should get is a popped fuse.

 

[Keith_J]

I believe you have a cucv not a Deuce or 5 ton.......the short answer to ALL cucv trucks is to just plug into an accessory plug in the fuse box on the fire wall......some one correct me if I am wrong but the cucv's already have 12 volt in there. I thought that I read on here a few times that they were wired that way....it's the reason behind the confusing 2 batteries and 2 alternators on those trucks.

CUCVs other than M1010 and certain M1028s used a pair of 12 volt alternators. Meaning you can tap into either battery without worry about balance. Yes, you CAN tap into the top battery and get 12 volts, you just use the 12 volt positive for the negative and you have 12 volts! But if you use the chassis for negative, you get 24 volts. But to do this, you must either fuse or circuit breaker the 24 volt side. And you can use the fuse box for negative, leading to a switched circuit.

Just like house wiring where you have two 120 volt legs, 120 volts to neutral, 240 volts leg to leg.

 

[doghead]

Keith, that post is utterly confusing! And incorrect

I would not suggest use of the rear battery on a CUCV, for any accessories unless they are isolated ground.

 

[Keith_J]

That is what I said. Not hard to do with modern mobile electronics.

 

[Rambling Wreck]

Is that what you said?

 

[ratat98]

We need a sticky for 24-12 volt conversions on the forum somewhere if there isn't one already

 

[BEANBELLY]

24v to 12 v

THANKS FOR ALL THE HELP WENT TO TMAMERICA GOT THE BRACKET MOUNTED 12V ALTINATOR. ADDED 3 DRY CELL BATTERYS 2 FOR 24V ONE FOR 12VOLT. ADDING THIS WEEK FUSE BLOCK FOR 12V SYSTEM. ADDED SOME PICS TO MY TRUCK ALBUM. THANKS AGAIN TO TMAMERICA

 

[meyerhvac]

We need a sticky for 24-12 volt conversions on the forum somewhere if there isn't one already

When I "remodeled "my 1009 I converted it to 12 volt. I pulled the passenger side alternator out, Installed a 12 volt starter,bypassed the pita glowplug circuit and installed a momentary push button switch that activates the glow plug relay.
I installed oil,temp,voltage gauges. Installed a blockage in the heater fan air intake so I can "recirc" cab air by opening the passenger fresh air vent. Installed a radio,4 speakers in the doors,side mount antenna,aux lighter plugs,driver side electric heater mounted on the dash so it will defog the door window, aux light mounted in the ceiling,10,000lb hitch and trailer electric brake actuator, and a few other goodies. I have put 30k miles on it,pulled a 2 place snowmobile trailer to the u.p. 5 times since with zero problems and I still have a spare alternator.
I would not change back from anything I have done, switching to total 12 volt is the way to go.

 

[JOateyNV]

Or you can just install this little gadget in your MV. http://www.steelsoldiers.com/showthread.php?101537-24-volt-solar-charger-with-4-12-volt-taps-and-8-24-volt-tabs
It let's you install all those things you can't live without.

 

[Rambling Wreck]

Or you can just install this little gadget in your MV. http://www.steelsoldiers.com/showthread.php?101537-24-volt-solar-charger-with-4-12-volt-taps-and-8-24-volt-tabs
It let's you install all those things you can't live without.

Apparently the link after your link is broken but just looking at the pics I don't think you could wire too much to it at 12v. I mean, it doesn't look very substantial. You might power a cell phone charger off of it but that is about all.

 

[wsucougarx]

Or you can just install this little gadget in your MV. http://www.steelsoldiers.com/showthread.php?101537-24-volt-solar-charger-with-4-12-volt-taps-and-8-24-volt-tabs
It let's you install all those things you can't live without.

Just bought one to try it out from a popular auction site. Cant go wrong with $130 shipped.

 

[Rambling Wreck]

Just bought one to try it out from a popular auction site. Cant go wrong with $130 shipped.

What amperage or wattage is it rated for?

 

[wsucougarx]

What amperage or wattage is it rated for?

Not sure, but here's the link to the manuf info.
http://www.pulsetech.net/PCMDS-PulseTech-Pulse-Charge-Monitor-Distribution-System-7377.aspx
I see the price for the kit anywhere from $279.99 here in SS to $1248 from the manuf. I figured $130 is a drop in the bucket. If I don't like it then I'll sell it.

 

[insanejecke]

Would this work on a 5 ton? i have some nice led Tow truck lights http://www.ledsnsirens.com/amber-plow-escort/60-tir-tow-truck-wrecker-lightbar.html that's what i have off One of our totaled rollbacks, And would love to mount it on the 816, and if i can do this set up i would like to add some new strobes i saw today at the truck supply store they were nice.

 

[MarcusOReallyus]

What amperage or wattage is it rated for?

That's a really good question. A really basic question for any device of this kind.

And the website doesn't say. Red flag, anyone?