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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: DebDav on November 08, 2009, 03:47:21 AM

Title: Belt driven generator
Post by: DebDav on November 08, 2009, 03:47:21 AM
Has anyone considered a belt driven generator?  I am riding in a 2006 Prevost conversion that has had a belt driven generator installed on the Series 60.  The toy provides power to the ?batteries? and then the 2 4000 watt intertors make 120VAC.  The system is plumbed and wired to allow the bus to use 120VAC for the refer, aux compressor and one roof air while driving.  With dash air, traveling is comfortable.  If more AC is required or while boondocking the main generator is available.

I have removed my bus air.  The location of the original compressor seems to be logical for a new generator.  Someone with smarts could use the original belt with gearing to drive the generator. 

Flame on.
Title: Re: Belt driven generator
Post by: bevans6 on November 08, 2009, 04:05:05 AM
I think a lot of people do that, but using the stock alternator on the bus.  My MCI has a 250 amp 24 volt alternator.  There is usually about 200 amps minimum left over to what I do with it, which is lots to power a 24 volt inverter.  I don't see any reason why you couldn't install such an alternator, and paying attention to the speed of the alternator and the power requirement of the belt drive.  Mine is oil cooled, to get the big current reliably for a continuous period to run the stock bus AC fans, and has four 1/2" belts.  I don't know what speed it runs at, and I shudder to think how much horsepower it take to run it, although I recall that being discussed.

The problem for me is being able to afford the inverter!  If you follow this path, then look for a 24 volt alternator since the distribution wiring to the battery bank, which probably isn't in the engine bay near the alternator, is lighter gauge for the same power capability.  I do plan to do an upgrade to more batteries and a 3KW inverter to run the roof AC on the road at some point.  It seems ironic to remove the bus AC system so that I can pay several thousand to install equipment to run a far less capable AC system while driving but there you go.  I can't quite remember why it's such a good idea at this instant...   ::)

Brian
Title: Re: Belt driven generator
Post by: robertglines1 on November 08, 2009, 04:39:49 AM
a thought;I put my 7.5 kohler generator where the bus air was located(compressor).With all three Airs and anything else I want it takes 1/2 gallon of fuel to run per hour.(water cooled on gas).so what would a system like your talking about cost and what are the returns..I had the converters etc on my last coach ,when we did this one we did the math and just couldn't justify the additional cost for our level of use ..We use from 5 to 15 thousand miles a year.When the original bus air fails it is super expensive to fix and I have been told is a major expense for charter operators. Not knowing where you are on your conversion.I hope this helps... and remember the old saying KISS......keep it simple stupid.....fits ME to a T.....good luck and do it your way.
Title: Re: Belt driven generator
Post by: luvrbus on November 08, 2009, 07:35:18 AM
FWIW Country Coach Prevost uses a belt driven generator to make 120 v power while driving with out the use of inverters, it is constant voltage at variable speeds 120v not 12 or 24 volts and I believe that is what you are referring too a very expensive set up around 6 grand and I forgot the brand name.  



good luck
Title: Re: Belt driven generator
Post by: Gary '79 5C on November 08, 2009, 01:40:04 PM
Not sure what your battery bank voltage is, However If I had (2) 4000 watt inverters, I would be looking to match a bus alternator with that battery bank voltage.

If you have a 48 volt setup, then I have failed in my thinkin' But yet another question from my feable mind, If you have say a 12volt chassis system and a 48 Volt bank,
Is there a vanner that would bridge from a 12V source to a 48V bank ?? Or better manner to get the 12V to 48V, stepup transformer.

My point without the wandering is to stay with the two inverters, as you have alot of capacity there.
Title: Re: Belt driven generator
Post by: belfert on November 08, 2009, 02:53:06 PM
If the Prevost has a battery bank and two inverters then it probably has a second 24 volt alternator.

I don't know about Prevost, but I have read that a lot of newer coaches now use two alternators instead of the big DN50 to provide enough power.  Two alternators provide redundancy plus smaller units are cheaper to fix or replace.
Title: Re: Belt driven generator
Post by: buswarrior on November 08, 2009, 03:53:01 PM
Standard install for some years now is twin alternators in the coaches.

Before that, popularly a small back up was jammed in there off a spare pulley to back up the 50DN.

With electronic engines and transmissions, it can't get home on its own after an alternator failure like a mechanical coach can...

Twins also have an edge in available power at idle over a single.

Redundancy is the name of the game.

A second alternator in place of the AC compressor sounds like a great idea, and has been done by quite a few busnuts, both 24 and 12 volt, as their design required.

happy coaching!
buswarrior
Title: Re: Belt driven generator
Post by: DebDav on November 09, 2009, 04:41:48 AM
I have already removed most of the bus air.  Reason: I 'personally' feel that as bus air is usable only while moving, I do not want to maintain that older redundant system and, hopefully efficient use of space for generator, batteries and outdoor cooking and

If there are 2 existing generators,  I will need assistance in comprehending wiring to coach system.  If a new generator is installed in the bus air compressor location,  I think that I have found schematics for installation.

This just opens more doors and, sadly, means more time and money--one way or t'other!