Community Forums

lundy · 10-16-2017, 07:19 PM

I recently viewed a video where a Road Trek Class B motor home substituted an engine based generator for charging rather than using a Cummins Generator. They have a auto start feature that fires up the engine when the battery reaches a certain level. Has anyone experienced use of this type of charging? What do you feel is the advantage or disadvantage of this type system? I have had several motor homes, all with generators. I really have never had a lot a use for a generator but feel that I need one for dry camping and it sounds like a good idea just from a maintenance point of view. What do you think?

Brentw · 10-16-2017, 07:26 PM

I have no experience with that system, but advantage is that there is only one engine. Not sure how the vehicle engine would be driving a generator - pto perhaps??
Disadvantages- running a 2-300 hp engine for a 5 hp job.

pfm41 · 10-18-2017, 06:11 AM

Most if not all diesel engine manufactures discourage running the engine with no or very light load for extended periods because the engine would not maintain operating temperature which leads to all sorts of issues. To me it sound like this application is contrary to proper operation of the engine; surprised the OEM people would allow it.

aether_one · 10-18-2017, 06:22 AM

Since we are talking about a class B motorhome here I can easily see where a high output alternator on the engine would be a good substitute for a generator; either built-in or stand-alone. Space is a huge compromising factor on class Bs.

ht4cae · 10-18-2017, 06:31 AM

The ones I know of are used in ambulances and by the military. It's a separate device. On a small class B they only have one battery, so it doesn't take much to charge it.

Old Scout · 10-18-2017, 06:46 AM

Don't own a Class B but seems like the main issue for having a built in genset is A/C. If it just about keeping a small battery bank charged, perhaps the add-on engine alternator would work. Any amount of dry camping where you need/want to have some A/C would dictate a separate genset--IMHO.....

Slolane · 10-18-2017, 01:48 PM

We have a Roadtrek CS with the underhood generator. It also has 400AH of lithium batteries and 140 watts solar. The advantage is that the alternator can charge the batteries fairly fast compaired to AGM batteries.

When the voltstart is activated it will monitor battery voltage and auto start when voltage drops below ~ 12 V. and run for 30 minutes. It will repeat a maximum of 5 times.

We have run our house A/C for several hours with it. Obviously you cannot run the A/C full time with it. We get a site with shore power if we camp in hot areas.

Mikes47 · 10-18-2017, 04:56 PM

We have an Advanced RV with the second alternator. This 2nd alternator charges the lithium battery bank while driving. It is configurable as to at what SOC it kicks in to start the engine and for how long the engine runs. Folks who choose a 'B' are generally on the go for part of each day, so the batteries are generally well-charged. But if we do stay in one place for a couple of days, the system kicks in to charge up the batteries. Advantage: small size, quieter than the stand-alone generator. Disadvantage: when the engine starts, it goes through its regular start-up sequence. Lights and radio might come on, TPM might yell if its been cold, etc. Easy to plan for the contingency and avoid the noise.

lundy · 10-21-2017, 12:03 PM

Slolane, you can actually run the A/C with battery power? That being said, sounds like a good combination if you travel with pets and you want them to stay cool while sipping wine on the deck of a nice winery and not leave a stand-alone gen running.

Slolane · 10-22-2017, 02:43 PM

Quote:

Originally Posted by lundy

Slolane, you can actually run the A/C with battery power? That being said, sounds like a good combination if you travel with pets and you want them to stay cool while sipping wine on the deck of a nice winery and not leave a stand-alone gen running.

Yes. We've left for an hour or two using the batteries and Voltstart to run the A/C.

twinboat · 10-22-2017, 04:59 PM

Is it a 13,500 BTU or a smaller 8000 BTU air conditioner?

Slolane · 10-23-2017, 07:59 PM

Specs list a 11000 BTU A/C

werdone · 12-31-2017, 06:43 AM

Quote:

Originally Posted by Slolane

Yes. We've left for an hour or two using the batteries and Voltstart to run the A/C.

Jumping on this thread a bit late but my wife and I are looking at the Roadtrek CS Adventurous based on the solar and battery charging system. We want to boondock and this looks like a good setup for that. Any experience with staying out for extended periods of time away from shore power? And does the solar provide adequate battery charging for lower consumption items?

Mikes47 · 01-01-2018, 07:29 AM

Weredone - you might want to read this article to get a "real-world" perspective on how solar on a B performs: https://advanced-rv.com/impact-of-solar-panels/. Bottom line, in my opinion: It all depends!