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Best gas generator for a backup battery charging?

HewSmith

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Any thoughts on a good, reliable, fuel efficient, somewhat quiet gas generator to keep on hand to charge batteries on days there's not enough solar?
I have Victron MultiPlus-II 48/3000/ 35 amp charger.
Thanks
 
Honda’s are really proven and reliable option. I’d also consider LPG conversion kit as it gets rid of modern gasoline storage&stability problems. 10 yr old LPG canister runs just the same as fresh.
 
Westinghouse makes a 3000w tri-fuel inverter genset. It isn't priced like a Honda, but seems to be as reliable from what I've seen / read. Also has parallel capability should your needs grow (and it still be available). Like was mentioned Propane is much more stable for long term storage, and a NG hookup means never having to say you're sorry
 
I am right at this moment using a Genset (Champion 41552) to charge a 24V Battery Bank. Using the L5:30 (120V/30A) plug, the Inverter/Charger (Samlex EVO-4024) is pulling 120V/25A to charge at 79A (just looked it floats a little because I use Passthrough power as well). This is a "Dirty" generator, a basic Mod Wave Contruction Generator (9000W Peak) that I use for my Welder or Air Compressor system when needed or to charge in some cases.

NOTE: Regardless of Inverter/Charger system you use, whatever power is provided by a Genset is also passed THROUGH the system to your home. In my case right now, I am getting 120VAC @ 64Hz Mod Sine. This is generally NOT good for fine electronics etc. PURE SINE is the preference for all things digital.

Inverter Generators which output a clean 120/240 @ 60Hz Pure Sine is obviously what everyone wants but you have to pay for that.

WARNING ABOUT GENNIES !
This Company IMPORTS Many generators from China with BrandNames like Energizer - DO NOT GET FOOLED ! These have NOTHING to do with the Brand Label "Companies" and they are utter CRAP ! See here: http://www.midlandpowerinc.com/
BTW: They are NOT the only Shlock Floggers. I have a couple of grand worth of JUNK if you want.... Lessons Learned Dept.

Honda, Champion and several others are Most Absolutely worthwhile. I can ONLY SAY GOOD THINGS about My Champion equipment. With Propane (which won't sour over time) you can certainly have good backup power to charge battery banks.

NOTE: If you want to use AGS (Auto-Gen-Start) port on an Inverter/Charger System you will require a GSCM (Generator Start Control Module) which takes the AGS signal and starts/stops the genset. Here is a link to the standard North American version below. In the "Wiring Diagrams PDF", all of the Generators that support a GSCM are listed. If a Generator is NOT in that list, then no company can produce a GSCM or it. https://atkinsonelectronics.com/gscm-mini-60hz-usa-canada/

Hope it helps, Good Luck.
 
Another alternative to LPG would be Alkylate gasoline if it is available in your neck of woods. Aspen is one popular brand here in Europe.
AFAIK promised 5 year storability and based on how it looks and smells after 5 years I'm pretty it will run a generator even after another 5 years.
 
Another alternative to LPG would be Alkylate gasoline if it is available in your neck of woods. Aspen is one popular brand here in Europe.
AFAIK promised 5 year storability and based on how it looks and smells after 5 years I'm pretty it will run a generator even after another 5 years.
Aspen is in the North America market but the popular one here is Trufuel.
I keep a liter on hand, just to tide me over until I can get to a pump.
I really should set my car up so I can get gas from the tank which has an anti-siphon filler neck.
 
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When you can charge with your system equipment that’s a benefit. If you have to charge at DC 12V a lot of the generators only have a dismal 10A 12V.
That’s another benefit to the aio type inverter-chargers in so many applications- useful charging amps.

Anyways- what about Avgas with a double-dosage (storage) of Marine Stabil? Would that store well? I’ve always meant to do that, never have gotten to it
 
I really like the Predator 3500 Inverter generator from Harbor Freight. I've had my share thanks to the 1 year warranty package. lol Changing from off-grid to solar, but will always have one as it has done us well (over 2,000 hours with regular oil chnages).
 
Thanks for all the suggestions, I'll need to check them all out, but i do like a Honda.
I've had a Honda push mower for 20 years until the body rusted out.... motor still started every time. I gave it to someone and they welded up the body and as far as i know still using it.
 
You will pay more for a Honda but you will get your money's worth. Now do pay close attention to their info, what is most important is their "Continous Running Watts" which is most important to consider for battery charging. Also if you are using "pass through" power while charging the generator has to be able to handle that too.

BTW: If anyone wants to Convert a Generator to LPG or Natural Gas there are "Kits" available to do so for many models. This company below makes some good quality kits and they are actually fairly affordable to boot.
 
I agree with the Honda generator recommendations. Particularly the Honda Inverter generators, ie EU3000is.

With an inverter type of generator, as your load decreases, the generator rpm, fuel consumption, and noise decreases.

There is no comparison between a normal generator, running 3600 or 1800 rpm all the time and a EU3000is that starts at about 1800 rpm and after a few minutes drops to a nice, gas sipping 1200 rpm. Also consider the noise.

I live in an off grid neighborhood is western Wa. and I have at least four neighbors running EU3000is's, for more than 5 or 6 years. In the winter months, with our lack of sun, they get their workout. I've heard of no reports of trips to the service shop.

I even have one neighbor who bought his unit used, from a rental shop, and he's been running for 5 winters.

And they are easy to convert to Propane.

Good luck
 
I like this one.

pros
inverter for clean power and less frequency jitter​
Open frame for easier maintenance.​
RV plug​
Big gas tank​
3500 running watts​
hour meter​

cons
nearly 100 pounds​
no wheels​
more noise than closed frame units​
 
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Steve S said
NOTE: If you want to use AGS (Auto-Gen-Start) port on an Inverter/Charger System you will require a GSCM (Generator Start Control Module) which takes the AGS signal and starts/stops the genset. Here is a link to the standard North American version below. In the "Wiring Diagrams PDF", all of the Generators that support a GSCM are listed. If a Generator is NOT in that list, then no company can produce a GSCM or it.

Thanks for the tip on the remote start kit, I will check into it more. Looks like a solid unit at a reasonable price.

The one thing missing in their documentation is the word 'choke'.

When using gas, I've never been able to start a EU3000is, without using the Honda's choke.

Do you have any experience with starting generators that do not have an 'auto-choke' ?

Thanks
 
EU3000is that starts at about 1800 rpm and after a few minutes drops to a nice, gas sipping 1200 rpm. Also consider the noise.
These Honda inverter generators are running a lot faster than you'd guess listening to them. The eu2000i low idle (eco on) is 3,000 RPM, high idle (eco off) is 4,300, and max is 5,000. The eu3000i high idle (eco off) is 3,500 RPM. I haven't seen its low idle published anywhere and don't have one to measure, but if the eu6500i gives a hint, its high idle is 3,300 and low idle is 2,400. If guessing, I'd expect the eu3000i's low idle to be higher than 2,400.
 
Any thoughts on a good, reliable, fuel efficient, somewhat quiet gas generator to keep on hand to charge batteries on days there's not enough solar?
I have Victron MultiPlus-II 48/3000/ 35 amp charger.
Thanks
Your 35 amps at 48 volts is 1700 watts. Try to stick to a generator that has a max continuous output of that or even a little lower and then just program the multiplus to only take what the generator can provide at its max continuous. If you get bigger, your efficiency goes down.

You cant go wrong with Honda or Yamaha
 
These Honda inverter generators are running a lot faster than you'd guess listening to them. The eu2000i low idle (eco on) is 3,000 RPM, high idle (eco off) is 4,300, and max is 5,000. The eu3000i high idle (eco off) is 3,500 RPM. I haven't seen its low idle published anywhere and don't have one to measure, but if the eu6500i gives a hint, its high idle is 3,300 and low idle is 2,400. If guessing, I'd expect the eu3000i's low idle to be higher than 2,400.
My EU2200i runs a bit slower than that, 4k or so tops. Don't remember what it was on idle, I want to say in the 2000rpm range.

For occasional backup power, there are lots of good options. For anything I was going to put serious hours on, I would pony up for the Honda, without a doubt.
 

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