Two Alternators On One Tractor?

[npalen]

Today I happened to come across the original alternator that I had replaced on my Kubota B9200 a while back. Come to find out it was a broken wire and not the alternator at fault.

Anyways (is that even a word?) the question occurred to me whether two alternators could be mounted in "parallel" with a longer fan belt. I know, seems kind of silly, but looks like the AC voltage going to the regulator would be the same but I suppose the question is whether the regulator could handle the "double" amperage.

I suppose, if one was really wanting more output for a bunch more LED lighting or whatever, a compact but high output alternator could be had. There wouldn't be room for a full size due to the engine side shields on this particular tractor.

Is this wild idea even worthy of discussion?

 

[shui5612]

Double alternators can be mounted no problem...

It will suck abit more engine horsepower but assuming you run a separate electrical system then you wouldn't get 2x amperage.. you would have 2 systems that each have let's say 30A but not one system with 60...

Having one system trying to handle double amperage means you would have to find other places that won't be able to handle the load.. fusebox.. cables.. etc..

But if you leave the oem system on oem and use the second alternator for auxiliaries such as light bars etc there's no reason why it won't work.

Personally I think 2 smaller alternators is better than one massive one.. most full size diesel trucks Have 2.. probably due to them heating up less, needing smaller gauge cables, being jelly bean parts off other cars versus having to order, maintain another part... etc..

Hope this helps.

 

[Industrial Toys]

Friends of mine who do upfits for commercial service vehicle usually put in larger alternators when required. Not so much a second. I'm guessing, usually there isn't room.

I had a Diesel ARGO prototype with a small 2cyl Rugarini Air Cooled Diesel. The magneto wasn't enough to run several cooling fans, so I put in a small GM alternator. That thing would not run the alternator at idle so I had to raise the idle and then the snowmobile clutch started to grab. I never got this solved and just sold it.

A small Diesel does not have a lot of power at idle.

 

[BleedingOrange]

Led lighting requires less power, so I would be keeping that one for a spare.

 

[npalen]

Double alternators can be mounted no problem...

It will suck abit more engine horsepower but assuming you run a separate electrical system then you wouldn't get 2x amperage.. you would have 2 systems that each have let's say 30A but not one system with 60...

Having one system trying to handle double amperage means you would have to find other places that won't be able to handle the load.. fusebox.. cables.. etc..

But if you leave the oem system on oem and use the second alternator for auxiliaries such as light bars etc there's no reason why it won't work.

Personally I think 2 smaller alternators is better than one massive one.. most full size diesel trucks Have 2.. probably due to them heating up less, needing smaller gauge cables, being jelly bean parts off other cars versus having to order, maintain another part... etc..

Hope this helps.

So one battery or a second battery on an isolated circuit?

 

[shui5612]

You can use one battery but the "best" is 2 batteries.. that way you have a backup system too.. but all of this is getting too big of a setup for a small-medium tractor in my opinion..

 

[Threepoint]

Here's a thought. If you have room to mount the second alternator, a regulator, and in inexpensive inverter, you could have onboard 120v AC power for small tools and appliances. Don't know if you'd need a small dedicated 12v battery between the regulator and the inverter to stabilize the output.

 

[dieselscout80]

GM trucks had a option for dual alternators.

 

[npalen]

Here's a thought. If you have room to mount the second alternator, a regulator, and in inexpensive inverter, you could have onboard 120v AC power for small tools and appliances. Don't know if you'd need a small dedicated 12v battery between the regulator and the inverter to stabilize the output.

Now that's interesting!

 

[4570Man]

It wouldn't take much of an alternator to run pretty substantial LED lighting. Unless you have a specialized use in mind I wouldn't bother.

 

[shui5612]

He probably won a lot of thirty 30-50inch LED bars...

Three under the tractor.. three in the grill... six on the cab.. two on the backhoe.. three on the loader.. one in the engine bay.. two on the bucket...

Rumours say when the flux capacitors is charged enough to power them all, Australia's solar panels work at 50% capacity...

But on a serious note, on a bigger tractor I can see the use of having a second alternator...
The bigger tractors simply have more room /power to spare and space to mount electronics/lights etc.
As for the 120v power...
I'd get a 1200W silent inverter generator... really quiet.. briefcase size.. and would cost less /use less fuel /provide more power than having a converter..

Over all tractors don't have the big current draw even with all the lighting you can imagine and cameras etc.. since most things can be powered off hydraulics.. now if he had in mind some kind attachment that uses electric cylinders and motors etc.. then it would be useful..

Gotta remember that a led bar gives way more light than the old 50W halogen lights.. now if you had half a dozen of those mounted then maybe a second alt would be needed/helpful..

 

[rswyan]

Today I happened to come across the original alternator that I had replaced on my Kubota B9200 a while back. ...

Given the vintage of your machine, I'd be wondering if it is even an alternator (higher output) as opposed to a dynamo (lower output)

My B2910 - a more recent machine - came stock with a dynamo ... although there is a higher amp alternator option available for it from Kubota.

 

[Threepoint]

Here's a thought. If you have room to mount the second alternator, a regulator, and in inexpensive inverter, you could have onboard 120v AC power for small tools and appliances. Don't know if you'd need a small dedicated 12v battery between the regulator and the inverter to stabilize the output.

Further to this idea, I don't know the output of your spare alternator, but whether it would be large enough for this would depend on what tools you'd want to power. Ditto with the second battery you'd install. I did a quick search online and came up with a thread on another forum from 2011 that discusses doing this. Heck, you might even find a YouTube video on it by now!
http://www.mytractorforum.com/74-barn/214924-inverter-question.html

 

[Threepoint]

[snip]
As for the 120v power...
I'd get a 1200W silent inverter generator... really quiet.. briefcase size.. and would cost less /use less fuel /provide more power than having a converter..

True, but maybe not as much fun! :dance1: I remember seeing an article years ago in "Four Wheeler" magazine showing how to install an onboard inverter for AC power in, I think, a Ford Bronco. The receptacle was mounted in the grill! The article did discuss the sizing of the alternator and said upgrading might be necessary for some vehicles.

The newer inverter-style briefcase generators are sweet, and much cheaper these days (see Harbor Freight's newest entry). But they're not all that lightweight, and would still need to be carried on the tractor somewhere. I'll carry a small 3000w generator on a carryall when I know I'll need AC in the field. But having power already on board would be nice.

 

[npalen]

Already have all the LED lighting installed that I need and enough remaining capacity with the existing electrical system.
Just wanted to discuss the idea of two alternators.
The B9200 has just the dynamo.

Edit: Well I do have a 2000 watt inverter generator. Perhaps I could mount that on the hood.

 

[Redneck in training]

You can't parallel two alternators on the AC side (upstream of the regulator) unless you run them in phase lock. That is pretty much impossible on a tractor. You can parallel them on the the DC side. The generator with higher voltage will take all the load until it maxes out then the second one will start to contribute.

 

[npalen]

What is the main difference between a dynamo and an alternator? Output?

 

[Dave M7040]

What is the main difference between a dynamo and an alternator? Output?

The dynamo has permanent magnets inside to create the magnetic field. The alternator has coil winding to create the magnetic field and thus can be regulated as far as its power output by adjusting the current provided to the field windings.

With the dynamo, it puts out power based upon engine rpm. The rectifier converts it AC output to DC to charge the battery. Excess power is just turned into heat in the rectifier.

Some model early Kubota's had dynamo's with 3 output wires whereas most have only 2. On these machines, only part of the dynamo output was rectified to DC to charge the battery. The remaining AC output was used for lighting which, in those days was incandescent bulbs who did not care if they were fed AC or DC.

When someone with one of these tractors with AC powered lights embarks on a project to replace the original lights with LED's, they quickly get a big surprise as the LED, the D standing for diode, does not like and usually wont run on AC.

Dave M7040

 

[/pine]

An entirely different concept...This idea and picture was posted here several years ago...it was meant to utilize the mid PTO...

 

[npalen]

The dynamo has permanent magnets inside to create the magnetic field. The alternator has coil winding to create the magnetic field and thus can be regulated as far as its power output by adjusting the current provided to the field windings.

With the dynamo, it puts out power based upon engine rpm. The rectifier converts it AC output to DC to charge the battery. Excess power is just turned into heat in the rectifier.

Some model early Kubota's had dynamo's with 3 output wires whereas most have only 2. On these machines, only part of the dynamo output was rectified to DC to charge the battery. The remaining AC output was used for lighting which, in those days was incandescent bulbs who did not care if they were fed AC or DC.

When someone with one of these tractors with AC powered lights embarks on a project to replace the original lights with LED's, they quickly get a big surprise as the LED, the D standing for diode, does not like and usually wont run on AC.

Dave M7040

Very interesting! Thanks for the explanation.