Dual alternator on a 8.3

[pepepito]

Originally Posted by Robin97396

The information I keep finding is on Dodge Cummins Diesel Forum

cumminsforum.com

thedieselstop.com

Dual Alternator Kits - National Alternators

https://www.nationsstarteralternator...Kits-s/209.htm

You've probably seen these because they're so easy to find.

I'd start with making a custom bracket and setting up a belt, but I have no idea about the wiring.

Is this a safer method than trying to use the single alternator to charge house batteries?

Still they do not have brackets for 6.5L chevy diesel......sad...

[Brewerbob]

Edited too soon. Back in a sec.

[Brewerbob]

Grrrrr, did it again.

[Brewerbob]

Originally Posted by PNW_Steve

Here are a couple of engine compartment pics:

Same as mine or it looks that way. There is an L bracket that mounts the OEM alt in place. Buy one of those, flip it upside down and weld it to the existing one. and mount the second alt to it. A longer serpentine belt would be needed but no additional pulleys would be needed. So long as the belt is at a 90° angle going across the pulley it'll be fine.

Originally Posted by Robin97396

This will be interesting, and I'd say you've got more than a couple people wanting to copy this process.

Besides Steve, who's looking? I took pics (no measurements) but on my bus I think it would be super easy to do. I might just do it even tho I'm not remotely close to needing it myself. I don't know what the bracket costs... can't be more than $10 I would think. The second alt to make sure everything is aligned right would be the tricky part. There were NO flat nose buses in the junkyard. I've no idea if the alt's are different or not.

Originally Posted by superdave

you can get another pully to drive the alt like they do for ac. less stress on the existing belt. you will need to have a mount fabbed up but wont be too pricey.

I don't think another pulley is needed. Put the 2nd alt right next to the first. Route the belt around both but follow the rest of the routing as is.

Originally Posted by Robin97396

I like the redundancy theory of using two common inexpensive alternators that could easily be replaced while in a foreign country, like Kanada.

Or Mississippi.

Originally Posted by cadillackid

DUB cars with 5000 watt plus sound systems are often outfitted with lots of alternators and batteries
-Christopher

Those guys need to be lined up and shot. If you're going to waste that kind of money, you should just give it to me instead.

Originally Posted by Dead pirate

I run it through a 30 amp controller

30A controller? Um, how is a 30A controller going to control a 160A alt? I've no idea what the starter draws nor what dead house batteries would draw but 30A in the 12V DC world ain't all that much.

[Dead pirate]

Originally Posted by Brewerbob

Same as mine or it looks that way. There is an L bracket that mounts the OEM alt in place. Buy one of those, flip it upside down and weld it to the existing one. and mount the second alt to it. A longer serpentine belt would be needed but no additional pulleys would be needed. So long as the belt is at a 90° angle going across the pulley it'll be fine.

Besides Steve, who's looking? I took pics (no measurements) but on my bus I think it would be super easy to do. I might just do it even tho I'm not remotely close to needing it myself. I don't know what the bracket costs... can't be more than $10 I would think. The second alt to make sure everything is aligned right would be the tricky part. There were NO flat nose buses in the junkyard. I've no idea if the alt's are different or not.

I don't think another pulley is needed. Put the 2nd alt right next to the first. Route the belt around both but follow the rest of the routing as is.

Or Mississippi.

Those guys need to be lined up and shot. If you're going to waste that kind of money, you should just give it to me instead.

30A controller? Um, how is a 30A controller going to control a 160A alt? I've no idea what the starter draws nor what dead house batteries would draw but 30A in the 12V DC world ain't all that much.

I run the solar battery bank through a 30 amp controller.

Sent from my LGLS676 using Tapatalk

[Booyah45828]

You could have the alternator charging the vehicle battery. Then piggy back the charge controller off the vehicle battery so that it will charge it at the proper rate. Then have some sort of solenoid switch to keep them disconnected when the engine isn't running. That's how I would do it.

If you're using 24v house batteries. It's different.

I like the idea of having a 24v alternator and using that to specifically charge the house batteries. But I'm not sure how you could get it to regulate properly so as to not burn up the batteries by charging too rapidly, or burn up the alternator with too much of a load. It's possible though by monitoring charge level, amp load, and voltage and adjusting the field strength to keep it ideal. Just not sure if something exists in the aftermarket to do such a thing.

Could you mount the charge controller between the alternator and the batteries. Have the alternator put out 24v to the controller then have the controller throttle it to get what you desire. Will the controller take the kind of abuse in that situation or does it need a constant steady voltage? Would the alternator handle that kind of system?

[Dead pirate]

I like the idea of the piggy back between the bus battery and the charge controller. I wonder if there is a controller to regulate the charging and voltage.
Its a 12v system.

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[family wagon]

Originally Posted by Booyah45828

You could have the alternator charging the vehicle battery. Then piggy back the charge controller off the vehicle battery so that it will charge it at the proper rate. Then have some sort of solenoid switch to keep them disconnected when the engine isn't running. That's how I would do it.

I've been a proponent of this method for some time. It does a great job maintaining the battery in my electric-hydraulic dump trailer.

IMHO it's important to select a charger that is capable of boost mode operation. A buck or PWM design (ie, step-down only) would at best reach an output voltage 0.2 volts lower than what's presented at its input. If the alternator settles to 13.5-13.8 volts then the house battery being charged to 0.2 or more volts below that may not be able to reach 100% state of charge. A combination buck-boost charger could ensure the battery gets what it needs regardless of input voltage.

So long as you're looking for a buck-boost charger there's no reason one couldn't take nominal 12 volts in and make ~27 volts out for charging a 24 volt bank. I know voltage converters from 12 to 24 and 24 to 12 are common. If you could find one with an adjustable output voltage that didn't completely shut down in an over-current situation (ie depleted house battery) it would make a fine 2-stage charger. That's exactly what I use on my dump trailer: it's marketed as a "power supply" but its design makes it well-adapted for charging a battery.

[PNW_Steve]

Thanks Brewer Bob.

I am going to look closer at that and see if I can make it play.

Family Wagon, I think that you missed that my existing alternator is 12v and my house bank is 24v.

[Brewerbob]

Originally Posted by PNW_Steve

Thanks Brewer Bob.

I am going to look closer at that and see if I can make it play.

Any updates yet? I'll be at the bus today if you need better photos of mine or anything.

[PNW_Steve]

Originally Posted by Brewerbob

Any updates yet? I'll be at the bus today if you need better photos of mine or anything.

Sorry, life got in the way. I have been extremely busy and got distracted. Now I am 300 miles away form the bus. I will check when I get back to the bus. It will be a week or two.

[Brewerbob]

Originally Posted by PNW_Steve

Sorry, life got in the way.

I've never had that happen. I'm not that far from the bus and still need to spend more time on it.

[Steven UK]

Interesting reading, I would like to just throw this out there because if someone is running a second alternator just to charge house batteries there are going to be issues topping the batteries off I.e. It will never happen. You could look at one of these if you are running deep cycle batteries that will make better use of and make the batteries last longer. This box will control 'bulk' 'absorption' and 'float' stages of charging just like a good mppt solar charger. It should mean less engine starts when boon docking...

Balmar Digital Duo Charge

Also if someone has a good sketch of a bracket for a popular engine / alternator setup I have the facilities to make them. And they would be much cheaper than the kits mentioned earlier. Good luck.

[PNW_Steve]

Originally Posted by Steven UK

Interesting reading, I would like to just throw this out there because if someone is running a second alternator just to charge house batteries there are going to be issues topping the batteries off I.e. It will never happen. You could look at one of these if you are running deep cycle batteries that will make better use of and make the batteries last longer. This box will control 'bulk' 'absorption' and 'float' stages of charging just like a good mppt solar charger. It should mean less engine starts when boon docking...

Balmar Digital Duo Charge

Also if someone has a good sketch of a bracket for a popular engine / alternator setup I have the facilities to make them. And they would be much cheaper than the kits mentioned earlier. Good luck.

I will have solar to top the batteries off. I am planning on 1000-1600 watts of solar.

If it comes to having to fabricate a bracket I will certainly be talking to you.

Thanks

[TimN]

Originally Posted by PNW_Steve

I will have solar to top the batteries off. I am planning on 1000-1600 watts of solar.

If it comes to having to fabricate a bracket I will certainly be talking to you.

Thanks

Just curious if this ever got done and what it looks like. I plan on running a 48V solar array, so the thought of running a 48V alternator alongside a 12V alternator is very appealing to me.

[PNW_Steve]

Originally Posted by TimN

Just curious if this ever got done and what it looks like. I plan on running a 48V solar array, so the thought of running a 48V alternator alongside a 12V alternator is very appealing to me.

No progress yet.

[makaufmann]

Just reading through this thread. Anyone with any updates or progress. I'm designing, installing my house electrical system now. going with 24v. Is a second alternator charging at 24v just a myth or is it really possible for a 2001 International Amtran RE DT466? Thanks.

[Native]

A second alternator *is* possible, at any voltage you desire. You just have to find the alternator (and appropriate regulator), mounting bracket, proper length of belt to drive it, cabling to the batteries, batteries, and the place in the engine compartment that the bracket and alternator will fit.

[cadillackid]

if you arent into fabrication there are companies which make bracket kits for this very purpose.. dual alternators are a common item on ambulance chassis of which many were built on medium duty truck frames similar to school busses.. I have seen them built on IH 4xxx, and freightliner FL series chassis.. these would be similar in engine and space to the school bus chassis.. Bracketry systems, red-dot, and AP-air are companies that often make brackets for A/C's but ive also seen auxilliary alternator bracket kits in their listings as well..

[WiredForStereo]

I noticed this alternator setup in the Broccoli Bus video on Youtube:

Though it might inspire some ideas.