Author Topic: Back to all 24VDC (with a couple of exceptions)  (Read 2661 times)


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Back to all 24VDC (with a couple of exceptions)
« on: June 17, 2006, 02:00:13 PM »
DML, Nick and I started to discuss this in the Chat room this morning but 86Neoplan  ???  screwed up the board and nothing got settled. :o

Once we got used to the Chat Room and can get a group discussion going I believe it'll all work out OK.  For the most part those of us who've been there a while seem to, while it's not intended, set the others off to the side.  WE DON"T MEAN TO GUYS!

My MC5 has a 12.5 Kohler w/2 roof airs.  The generator is too big and too heavy!  I don't want to run that monster for just one roof air and the refrigerator while were traveling down the road with the sun in my eyes.  I'd as soon have a 2-3KW inverter and let that big 24v Alternator handle the load.  The generator is run by a 4 cylinder Perkins and while it's a sweet running's too heavy!  A little 8KW Kubota would be all I need.  That being said....

The only items I have on 12VDC are the CB radio and  the Halogen headlights (and I don't drive at night) so I could meld my (3) GRP 31 batteries and the generator Battery into a large 24V bank and do a tap for the CB and the headlamps.  Oh, the Jakes will be 12V too but for the little I'll use them they'd be OK on the same 12V tap.  I'm really wishing to get rid of the (2) 8D starting batteries...more weight to haul around. 

We're primarily going to be a post bus.  I'll let the next guy worry about how he wants to configure HIS bus after he buys it!

I'm in the process of removing the bus air...the compressor will come out this week. I'll keep the blower bit remove the evaporator and the condenser..and perhaps gain a bit more basement room.

I just can't see hauling around extra weight that isn't paying it's way.

Any thoughts?



  • Guest
Re: Back to all 24VDC (with a couple of exceptions)
« Reply #1 on: June 17, 2006, 03:34:24 PM »
I would get an equalizer for the 12 volt loads so you don't wreck the battery bank.  Don't you have 12 volt stuff like water pump and interior lighting?

I recently bought an 80 amp Vanner brand new off Ebay for $315 with shipping.  I think the same guy might still be listing them.  He seems to have a bunch.  The local bus repair place recommended a Sure Power equalizer over a Vanner, but I didn't want to pay an extra $200 or more for one.

Brian Elfert

Offline FloridaCliff

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Re: Back to all 24VDC (with a couple of exceptions)
« Reply #2 on: June 17, 2006, 05:25:58 PM »

You know, and it goes without saying that I would be willing to remove and dispose of that Ole 12kw for you. :-\

Just consider it a welcome to Florida gift to you this Winter. ;D

Oh yeah, NO charge either. ;)

On a more serious note:

I am using a Vanner and am pleased so far.

I have both 12 and 24 Vdc loads, I feel better having a seperate House and Start battery bank.

I ran down my starts on a 12Vdc tap when I first bought it and was sooooo happy to have the house bank that I could connect

through a solenoid to start it.

On the way to Timmonsville I had a brand new battery "Give up the Ghost" and it made it nice to switch in the house and start

from a rest area and keep going.  (FYI-Thank you again to Dallas for taking me to get my replacement)

1975 GMC  P8M4905A-1160    North Central Florida

"There are basically two types of people. People who accomplish things, and people who claim to have accomplished things. The first group is less crowded."
Mark Twain


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Re: Back to all 24VDC (with a couple of exceptions)
« Reply #3 on: June 17, 2006, 05:28:22 PM »
Brian, you're right about the 12V water pump.  That will only be used while on the road (when we stop at a rest stop or a Wal-Mart should we overnight) but while at the 'post' I'll use a pressure reducer and connect direct.

It really boils down to having a minimum of 12VDC stuff on my 24VDC bank.  I'll still have the battery capacity for the inverter and/or the generator for backup.  Have given thought to 110V magnetic drive Marine A/C circulating pump for the water with a check valve and surge tank.  The inverter should handle that just fine.

Thanks for your  input.



  • Guest
Re: Back to all 24VDC (with a couple of exceptions)
« Reply #4 on: June 17, 2006, 05:41:33 PM »
Hi Cliff!  Oh, I definitely plan to have another 24VDC starting bank.  But with the 24VDC house bank (and perhaps a heavy duty momentary Paralleling solenoid) I could always get something going.

Ya want the 12.5 Kohler with the roll-out mount?  Sure!  Find me a low time 8KW Kubota (preferably Onan), 120/240 radiator cooled (pusher fan) unit with less than 1000 hours (which has been treated as well as your daughter) and we got a deal!  Charlie and I will supervise the changeout!  I just bought a solid state controller for the genny which will monitor O/P, W/T, and O/S with a key start that I'll throw in with the deal! ;)

By the way, do you really know the origin of the "Cracker" tag which is attached to most native Floridians?  You won't belive it when I tell you!


Offline TomC

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Re: Back to all 24VDC (with a couple of exceptions)
« Reply #5 on: June 17, 2006, 08:45:20 PM »
The 8D starting batteries generally have 1200 CCA (cold cranking amps). I replaced my two beheameths with two Trojan size 31 with 1000 CCA.  I was recently at the Grand Canyon for two days, and was in the upper 30's in the morning.  The bus cranked easily and for the extra time (about 8 seconds worth) to get the cold beasty running (with a big puff of white smoke that quit very shortly)-and the batteries are 5 years old.  Needless to say, more than enough power to start the 8V-71N.  And if you have a tie in solenoid that can jump your deep cycle batteries incase the starting batteries need help, you don't need any more than the two size 31 batteries, ever-even in very cold weather.  Good Luck, TomC
Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.