Voltage Regulator for 4A084 alternator

Some of us plan to use the 4A084's original permanent magnet alternator for charging thier battery. The output of the alternator is about 40 volts AC at 3600 RPM. The original regulator-rectifier turns that into approx. 28.5 volts DC, for charging 24 volt batteries.

That's no good if you plan to have a 12 volt electrical system.

Fortunately, there's an easy, simple solution. Key West Controls makes a nice solid state voltage regulator/rectifier that works very well with the 4A084's alternator. Together they'll provide a 12 amp, 13.8 volt DC charging system, which is what we need for a 12 volt electrical system.

You can find it at Aircraft Spruce for $59.95. Thier part number is PS030.

Here's a link:

http://www.aircraftspruce.com/catalog/e ... pwrsup.php

Other places also carry it, but they all seem to have the same price.

My airplane friend turned me on to this, and says they work great. It's a simple 4 wire hookup. Ideally, it should probably be mounted to a fairly large piece of framework, to provide a good heat sink.

Duane

Thanks for the info on this, Duane.

DT

Duane and River Rat,

I may have mentioned this before in an earlier post. My buddy, that retired after building generators for Onan for around thirty years, told me I could get a suitable voltage regulator for the 084 alternator, off of a junk lawn tractor. A new one would cost about $30.00.

If you need more info, let me know. :)

Dave

Buster,

Tell us more. :) I knew you'd been holding out information. :( :)

Duane

Buster,

I just sent you a PM.

Duane

Or you could go to radio shack and get the parts to make your own rectifier even cheaper. :mrgreen:

Papee,

The rectifier part would be very easy, and pretty cheap. The regulator part, maybe not. You ain't gonna find anything you need at my Radio Shack. Mostly what they have are cell phones, computer gadgets, IPOD things, toys, and batteries. :(

Yeah, it could be built from scratch. But not everyone has the savvy or time to do that.

I just got off the phone with Buster, and he says he's got a line on a regulator/rectifier that'll also work, for about half the price.

Thanks,

Duane

Use to be able to buy anything electrical from Radio Shack... my local one is nothing more than a junk store these days.

OK, I just talked to Hank, and he found one on Ebay for
$31.95. It is a three wire hook up, and he claims it will charge 3 amps, to about 20 amps, depending the state of charge of your battery, and the speed of the engine. The Ebay item no. is 360148639768.

Hank said I do not need to buy a new one, there are lots of them on junked out lawn tractors. I think he said most any one with a built in alternator should have one. Hank does not buy a lot of new stuff if used is available at give away prices: :P

Dave

Buster,

You get the Gold Star this time. :D

That should work just fine, and a good scrounger can find one for free.

Duane

Hi Duane:

Know this an old post. I was wondering if anyone who used this product could tell me if they liked it. Im kicking ideas around for the charging system. I plan on running at least one light bar, navs/anchor, and comms. Thanks for any information.

I just installed the onan voltage regulator. I will get some numbers after I fire it up

Thanks Aewrigh. Just want to make sure I dont run out of light!

this is what i use. i needed to make my charging system work so i could hook my tach up to it. wouldn't work with mag hook up.
https://www.ebay.com/i/252945038062?chn=ps&dispItem=1