Generator Location

[richard5933]

Battery size would only come into play when there was no outside source, whether it be the bus alternator or the generator or the shore power.

You'll never run an inverter that large on a 'normal' size battery bank for very long, so I'd suggest you size your battery bank for the load you'll be using when you're boon docking and don't want to run your generator (assuming that you won't be running a/c from the inverter while boon docking.)

I've been told by the Trojan dealer in town that ideally the batteries should be charged at 10% of their total capacity, so keep in mind how large of a charger you plan to run.

[buswarrior]

Batteries aren't an issue for this topic.

In rough terms, 2 roof airs being driven by a 4000 watt inverter are consuming the same power from the alternator that the stock coach HVAC did.

So, continue with your thoughts, it is possible, and the coach can do it in stock trim.

I have the t-shirt.

happy coaching!
buswarrior

[neoneddy]

I run 2 Roof airs off my alternator.  Works great.

You get watts by multiplying Volts * AMPS .. so 24* 270 = 6,480 watts.  Now there will be some line loss and battery charging going on, as well having to run everything else.

With that said, if you upgrade most / all of your lights to LED like most of us have (side markers / tails / headlamps) then you've easily got 1000 watts of overhead / safety margin.

For my battery bank I run  4 6v Golf Cart Batteries, hoping to move to 8 this summer.  I have an Onan 4.0 BFA in the old AC condenser bay, it's mostly there for insurance.   The kicker here for me is also having 1900 watts of solar on top means, if we're driving down the road in the heat, I've also got power from the sun coming in to lighten the load on the alternator as well.  I mean I can run 1 AC  off solar alone .

[chessie4905]

Delco also makes a 450 amp 50dn alternator. Belt drive only. Same physical dimensions as the 270 amp version.

[buswarrior]

The big alternators are popularly hooked up to hoses feeding outside, cooler air right into them in the new coaches.

Higher engine room temps of the last 15 years brought this on.

Not a bad retrofit for a busnut.

Heat kills alternators, and some of us work 'em like mine ponies...

Happy coaching!
Buswarrior

[DoubleEagle]

Don't forget to calculate the cost (and weight) of all those batteries and inverters, and solar panels with their regulators, and all the associated wiring. You might find that a good used generator is cheaper.

[luvrbus]

Dual 2 smaller alternators are the trend now instead of the 1 big giant

[neoneddy]

Re: DpubleEagle :. I'm not saying don't do a generator, I have a small one as well. But I don't think we need 12kw ones for most of us. Most of the time we need a bigger generator for short periods of load like starting an AC or two, or other less than 1 hour use cases.

A good hybrid / assisting inverter can do wonders here. I use 1 victron Multiplus 24/3000 now, I'm planning on getting another for more headroom.

My costs so far

*= Standard items you'd need anyway.

* Victron inverter $1200  (there is a seller on Amazon selling them at this price)
* Small generator Onan 4.0 BFA $100  (used not working , just needed a carb clean)
* 4 house batteries - $420
* Battery monitor / inverter controller - $250 (built my own color control ccgx)
* Cables / ends etc $30
Solar panels $150x6 - $900 (used)
Racking and hardware $200
Mppt charge controller(victron)  $300
Cabling / connectors - $100

Total of standard items $2,000
Total of solar add on $1,500

Grand total $3,500


I will say I get my costs down by looking for deals and buying "good enough " items and then upgrading as something comes along. 

[luvrbus]

Load sharing inverters don't help much unless you are plugged in with low amps generator time depends on where you are at too,you won't get by here in AZ with 1 hour of AC time from May to Oct that won't happen even at night time .With the price of AGM batteries today 6-8D's like I have will buy a good diesel generator almost and you don't need a replacement every 5 to 7 years either   

[neoneddy]

Load sharing inverters don't help much unless you are plugged in with low amps generator time depends on where you are at too,you won't get by here in AZ with 1 hour of AC time from May to Oct that won't happen even at night time .With the price of AGM batteries today 6-8D's like I have will buy a good diesel generator almost and you don't need a replacement every 5 to 7 years either   

So..... don't be in AZ from May - Oct? :-)   

[luvrbus]

LOL but it is a dry heat, like a blast furnace