Small Backup Generator Install

[MAWilsonPE]

Although the Super SolarFlex system is capable of generating a lot of power when the weather cooperates, I decided to add a Honda EU2200i generator for backup power. This generator will provide 1800 watts continuously which is more than adequate for charging the batteries at full clip. I decided to install the Hutch Mountain propane conversion kit so I could avoid carrying gasoline. I tapped into the low pressure propane line just after the regulator.

I sourced the sliding tray from an Australian off-road company, it was the only tray I could find that extends the long way. I had to raise the hydraulic system pump and tank about 9-10" to make room in the front bay which meant extending the pump power wires a bit. I ran the generator power to the generator relay in the Progressive Dynamics shore power relay box.

I can simply slide out the genny, turn on the propane and start it up. I can charge the batteries at 100 amps (12v) or run one A/C unit and still have 40 amps (12v) available for charging.

Note that most stand alone generators do not electrically bond the neutral to ground resulting in an open ground fault. A simple fix is to jumper the neutral to ground on another three prong plug that is then plugged into the generator... no more fault.

Best Regards, Mike

[Creeker]

Nice clean install. A Genny simply fills in the gap and gives peace of mind no matter the weather or location. Excellent addition to your set up.

[AZ Traveler]

Mike,

Looks nice.

[kowbra]

Mike,

Do you worry about exhaust being vented below the bedroom?
I have a Champion on propane and while I was thinking of a solution like this, I was concerned about the exhaust... thoughts?

Brad

[MAWilsonPE]

Hello Brad,

I suppose there is a chance that some of the exhaust will get into the front compartment. That compartment is very well sealed from the living area though so I don't think I would ever get any exhaust inside the camper. I foresee using this generator only to charge the batteries for a few hours during cloudy/rainy days. I would never let it run overnight or when I am sleeping.

I have found an exhaust kit that includes silicone temperature-resistant tubing that can be used to route the exhaust under the camper but don't feel I need that, although it may help make it quieter, the front of the unit acts like an echo chamber

I would like to hear anyone else's opinion.

Thanks, Mike

[mlh]

Originally Posted by kowbra

Mike,

Do you worry about exhaust being vented below the bedroom?
I have a Champion on propane and while I was thinking of a solution like this, I was concerned about the exhaust... thoughts?

Brad

I’m not Mike but maybe I can help. My motor home has a 4000 watt generator that has its exhaust pipe directly under a bedroom window. It sticks out about 8 to 10 inches past the side of the camper. It’s was made that way. I have not heard of anything bad happening because of this.
Lynwood

[Creeker]

A simple 120V fan installed to blow outward would all but eliminate any worries. You could mount it inside from ceiling of storage compartment. Leave it plugged in to the Genny all the time. When Genny is started, fan comes on blowing any exhaust fumes outward.

[kowbra]

Thanks for the feedback all!
I think I will go ahead and try to mount my Champion in the front bay on a slide out. I have a 3200, so it will have to go in the larger front bay...

Great info!
Brad

[MAWilsonPE]

I did some checking and it turns out that this little generator, under load, burns propane at about the same rate as the RV’s furnace, roughly 1/3 of a gallon/hour, so makes the same amount of exhaust... for what it’s worth

Mike

[ScottN]

Mike — With the Super Solar Flex (SSF) package, if you connect a small generator while boondocking (e.g., Honda 2200), can you run the A/C? Sales rep told me the A/C will draw electricity from the generator, and not directly from the batteries, so the generator has to be at least 3500Watts. (This would be the same as a non-SSF; it would require at least a 3500Watt generator.)

[MAWilsonPE]

Hello Scott,

The Super SolarFlex system allows me to set the maximum power draw from the generator to 15 amps AC, anything above that can be made up from the batteries by setting the PCS to 20 or 30 amps AC. Having said that, I found that 15 amps AC is plenty for one A/C unit. I found that with one A/C running (~9-10 amps AC = ~1300 watts) I still had about 40 amps DC available for charging the batteries from this generator (Honda EU2200i has a surge capacity of 2200 watts, but a constant running capacity of 1800 watts)

This is possible only because of the soft starts on the A/C's. Below is a screen shot of the DC power draw from the batteries when starting one A/C unit (negative amps = a power draw). You can see the power spike when the fan starts (no soft start on the fan) that is double the steady power draw. A compressor with no soft start would probably spike to 180-200 amps DC (~2500 watts), too much for this generator. With soft start the power never exceeds 90-100 amps DC or ~1300 watts.

I don't think they are installing soft starts on the non-SSF units. Still, 3500 watts seems like a bit much for one A/C. Perhaps that is just the next step up in generator capacities.

I hope this helps.

Best Regards, Mike

[432bartman]

Mike that came out nice. I love the sliding tray. You're putting ideas in my head now..lol

[MAWilsonPE]

Hello Bartman,

Here is the link to the slide:

https://offroaddownunder.com.au/prod...erator-slides/

Again, this is the only slide I could find that slides out the long way. It is made for the Honda and even has the holes required to bolt down the generator. It locks in place in both the retracted and extended positions. 270 Aussie $ = $210 US, plus about $100 shipping, only took two weeks to get it. You can't order it directly on their website as it only allows shipping addresses in Australia. Send them an email. Tell Martine I sent you!

Best, Mike

[MAWilsonPE]

Here are some more of the installation details.

I built a wooden frame to raise the slide to clear the door. This frame is bolted to the floor of the front compartment from underneath. I found the front compartment floor is not nearly level and had to taper the base by almost one full inch front-to-back to get it level. I used 2x8's for the rectangular frame and topped that with 3/4" plywood.

The propane conversion kit is bolted directly to the frame. Enough space behind it is required to get your hand behind it to operate the priming plunger before starting.

As I mentioned before, I had to raise the hydraulic pump/tank by 9-10" to make room for the generator when retracted. This required longer power lines (4 AWG) to the pump. I also spent a lot of time and used many, many zip ties to neaten up all the power and hydraulic lines on this side of the compartment.

I zip tied together the propane feed line to the generator, the power cord, and the ground cord in such a way that I could slide the generator in and out without crimping any lines. This also allows me to put the generator cover on while retracted and not in use to protect it from all the junk (chairs, awning mats, portable dump tank, etc) bouncing around on the other side of the compartment

Here is a more detailed picture behind the genny.

[ScottN]

Mike,

Thanks for the detailed response. Very helpful explaining that the user can control how much electricity is drawn from the generator. You confirmed my understanding of how it works. And I agree, the “soft start” A/C units bundled with the SSF have a much lower start-up draw.

Regards,
Scott

[Camp CA]

Thanks for sharing. Might do the same for my new portable propane generator.

[Mark7]

Very impressive / clean install

[shredder22]

Genius!!