12V ACCESSORIES?

DOES ANYBODY KNOW HOW TO WIRE IN 12V RADIOS AND SUCH WITHOUT HARDWIRING DIRECT TO THE BACK BATTERY?<img src="emoticons/icon_smile_help.gif" alt="Help"> I WOULD LIKE FOR ALL 12V ITEMS TO TURN OFF WITH THE POWER SWITCH IF POSSIBLE.<img src="emoticons/icon_smile_vconf.gif" alt="Very Confused">

you need a 24v DC to 12v DC inverter (no more typing in caps)

40 dollars for one that is good to 20amps.

Or just hard wire a 12v line from 1 battery and connect it to a relay that is controlled by the master switch.

drawing voltage off one battery results in a lower charge for that battery. the alternator charges the batteries together, which will result in killing the non-tapped battery by overcharging.



it may sound like a wives tale, but i killed alot of batteries in my m38a1 this way before i knew any better. and i was only powering a CB radio.



whats wrong woth spending 40 dollars on a 20amp 24volt to 12 volt converter???

Nothing worng at all....just wanted to say there is another way to go about it.

I have used the method I mentioned on several pieces of heavy equipment and never really had a problem....but I also replace my batteries every 2 years regardless.

After a road trip of several days or so, the difference in battery voltage may be as much as 1/2 a volt from using the CB. I have a "Chargetek 500" dual battery charger/maintenance unit that restores the battery voltages to within millivolts as soon as I return home. It requires 120VAC so there is always a power cord running to the parked deuce. The 3x3x6 inch box is permanently installed behind the companion seat and wired in. My batteries are going on 5 years now, but I'm starting to feel uneasy about them away from home, so they are due for a replacement.

mcinfantry said:

you need a 24v DC to 12v DC inverter (no more typing in caps)

40 dollars for one that is good to 20amps.

Click to expand...

mcinfantry,

Got a source for a 24 DC to 12 DC inverter? I googled it and came up empty.


Thanks,

Al

Albin here are some links:




<SPAN style="FONT-SIZE: 8pt; COLOR: #3366ff; FONT-FAMILY: Verdana"><SPAN style="COLOR: #3366ff">http://www.powerstream.com/dc1.htm<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

<SPAN style="FONT-SIZE: 8pt; COLOR: #3366ff; FONT-FAMILY: Verdana"><o> </o><SPAN style="FONT-SIZE: 8pt; COLOR: #3366ff; FONT-FAMILY: Verdana"><SPAN style="COLOR: #3366ff">http://www.okoffroad.com/stuff-voltage-reducer.htm<o></o>

<SPAN style="FONT-SIZE: 8pt; COLOR: #3366ff; FONT-FAMILY: Verdana"><o> </o> http://www.surpluscenter.com/

Try searching for dc-dc converter in the link above, as well as Ebay and your usual seach engine. Dave

<SPAN style="COLOR: #3366ff"><o></o>

Got it!

Thanks,

Al

I do make gizmos on occasion and a small , say 3A, voltage regulator is not difficult to put together.
The unit would be encapsulated/water proof and have an input lead for 24-30 vdc and an output lead for 12-14 vdc plus a ground connection.
The case would be the size of a couple of cigarette packs.
One of these units could be installed for each 12v-device/radio. Typically a CB radio needs about 2 Amps max.
Your only consideration would be heat dissipation, the box will have to be mounted so that it can dissipate the same amount of heat as the device it's powering is using.
This is a linear type of voltage regulator, which is very "clean" and will not create any electrical noise.

If there is any interest in this, let me know. Initial cost $25.00 including shipping within CONUS (until I find out how much money I'm losing).

Bjorn, how bout a setup in a 3 or 4 pack... for trailer wiring... Any idea how many amps an electric brake controller pulls? This has been a 'pet project' of mine for a while, but havent got the knowhow and ambition to deal with it (too many other irons in the fire). Truthfully you would need a left turn/brake, right turn/brake and parking lights. A 12v lead for charging a battery would be nice, but I think that has different issues, as that would 'max' out your little box with no current regulation, wouldnt it?

Mike, the electronics is relatively simple here and I can package it by encapsulation for water proofing.
The biggest expense/problem is providing the interconnections. If you are prepared to just splice wires, that's no biggie, but if you need mating connectors then we are talking lots of money.

I'll check on the brake controller power consumption and will report back.

Made a "chopper" circuit about a year ago. It produced a 50% duty cycle square wave from the 24 volts supply and if only incandescent light bulbs are involved, they can run just fine on this square wave even when rated at 12 volts. With the square wave, they "see" an average of 12 volts.

Also in reguards to 12V trailer wiring there is this statement on http://www.powerstream.com/dc1.htm.


"These are also known as 24 volt voltage reducers, and voltage regulators. These DC/DC voltage reducing converters are suitable for running electronics, such as radios, CD players, computers, and CB radios. They are NOT usually suitable for headlights, motors, solenoids, or other electromechanical devices unless they are protected from inductive kickback and motor noise, and the current is rated for the inrush, stall, or locked rotor current of the load."



They look like they have pretty good amp ratings but I don't understand what else you would need to use something like this for a 12V trailer set up.

Bjorn, I actually have the connectors needed..... for that matter I could possibly send them to you for a build. My current financial state does not allow for anything, but I am planning...

BTW... the intervehicular cable that plugs into a deuce, for a trailer, is about $25 at www.flmv.net (damn another one). I was going to wire one of these to the converter, and then put a standard civvy 7 wire on the trailer side.

Yeah, you may send them to me for a custom build. Send me a PM when you are ready and I'll get you my address.

hey so i was reading all this square wave and chopper stuff...kinda makes the welder warket make more sense. any way so how hard would it be to go from 12 to 24 volt? I know it can be done, dewalt charges an 18 volt battery off of a 12 volt lighter plug. I would like to run my fuel pump on 24 volts. It does run on 12 but im not sure how good it is. There are a few other gizmos i wouldnt mind 24 volt for.

For low current devices, it can be done fairly simply (milliamp range), but for higher current applications a transformer will have to be used. The higher the current and lower the frequency the bigger the transformer.
Best to buy a dc to dc converter off the shelf.