Options for small 240V portable generators?

[dcg9381]

Yes, more expensive, but not that bad IMO. At least not for my modest home.

Considering a 5000 watt generator can be had for $500-$700, it's a big swing.
The cheapest 6KW inverter that can do 240V is $1500 and that's a rebrand straight off the boat.
5kWh lithium batteries capable of 100A (peak) are about $1200 each.

So you can either run a 5 kW generator for 3 hours for $500 to $700 or you can spend $1500 (inverter) and $3600 in batteries to do 3 hours of power... That's a factor of 10x.

That doesn't factor in the wiring and integration complication of the inverter. If you can't do that yourself, add another $5k.

And those costs are conservative.

New models of 240V battery backups are hitting the market for around $4k-$6k (before tax credit) that would run my entire home in the summer for almost half a day. Automatic switch . And what's really interesting is that they accept a 120V input for charging - even while simultaneously outputting 240V to the house. That means I could hook up a small 1,000W - 2,000W inverter generator and have infinite run time by refilling the gas tank once per day. And those small inverter generators absolutely sip gasoline and are extremely quiet.

Curious what your power requirements are? To do this small scale, say 5-6kW you'll need isolated critical circuits. To do a "whole house" - 20 kW (100A) you're talking about a pretty damn good chunk of change compared to a 20kW generator and ATS.

BTW, I agree with everything you're saying here about implementation... But it's hard to retrofit an existing house to properly use 5-6kW of battery backup.

 

[AA/FC]

I'm starting to see options for "linked" generators that are inverter and can do out of phase (240V) mode, not just in phase (more amps) mode.

Yep, check this one out. It's fuel injected, too!

 

[theoldwizard1]

Yep, check this one out. It's fuel injected, too!

I don't understand why any company/customer would be willing to spend on fuel injection when today's carbureted engine work well, cost less and meet all current emissions standards.

Sure, they have the POTENTIAL of eliminating some fuel problems caused be allowing fuel to dry up in the carburetor bowl or condensation to add enough water to the gas tank to prevent the engine from starting.

(That reminds me. Time to exercise my generator ! Probably should drain its tank and add fresh E10 !!)

 

[PCustoms]

And what's really interesting is that they accept a 120V input for charging - even while simultaneously outputting 240V to the house. That means I could hook up a small 1,000W - 2,000W inverter generator and have infinite run time by refilling the gas tank once per day.

I'm not an expert, but I'm fairly sure that violates a few rules of physics...

 

[wyliesdiesels]

Yep, check this one out. It's fuel injected, too!

and if you need a lot of power, go with a pair of these

GENMAX GM9000iE 9000 Watt Gasoline Inverter Generator with CO Detect

Engine Model: 192F/P-2 Type: Single cylinder,four stroke Displacement: 458 Max.Power(kW): 10.5 Rated Power(kW): 10 Bore×Stroke(mm): 92*69 Condensation Ratio: 8.8:1 Starting System: Recoil Start/ Electric start Ignition System: Transistorized Magneto SPARK PLUG F7RTC、F6RTC,F7TC、F6TC、NGK BPR6ES...

www.genmaxpower.com

 

[wyliesdiesels]

I'm starting to see options for "linked" generators that are inverter and can do out of phase (240V) mode, not just in phase (more amps) mode.

yup like this bad boy

GENMAX GM9000iE 9000 Watt Gasoline Inverter Generator with CO Detect

Engine Model: 192F/P-2 Type: Single cylinder,four stroke Displacement: 458 Max.Power(kW): 10.5 Rated Power(kW): 10 Bore×Stroke(mm): 92*69 Condensation Ratio: 8.8:1 Starting System: Recoil Start/ Electric start Ignition System: Transistorized Magneto SPARK PLUG F7RTC、F6RTC,F7TC、F6TC、NGK BPR6ES...

www.genmaxpower.com

 

[mike93lx]

The cheapest 6KW inverter that can do 240V is $1500 and that's a rebrand straight off the boat

1200 for a Briggs q6500. I got mine for a grand, but that was the before times

 

[AA/FC]

and if you need a lot of power, go with a pair of these

GENMAX GM9000iE 9000 Watt Gasoline Inverter Generator with CO Detect

Engine Model: 192F/P-2 Type: Single cylinder,four stroke Displacement: 458 Max.Power(kW): 10.5 Rated Power(kW): 10 Bore×Stroke(mm): 92*69 Condensation Ratio: 8.8:1 Starting System: Recoil Start/ Electric start Ignition System: Transistorized Magneto SPARK PLUG F7RTC、F6RTC,F7TC、F6TC、NGK BPR6ES...

www.genmaxpower.com

Yes, I own that same generator except mine is the "D" version (dual-fuel) that I use for home backup.

Genmax now makes a 10500 tri-fuel... which would be nice for my application but I will use the dual fuel 9000 for now.

 

[ebj]

Thanks, Jason. I mentioned in another post that my load will be no more than 2000W at one time. Most of the time about half that. I think a genny rated at ~3500W constant is the correct size.

As I've mentioned a couple times now, you can calculate the starting wattage of your HVAC if you have extended data chart from the manufacturer. I have calculated this and 4000W startup should be enough. Constant wattage for my HVAC is no more than 1000W. It is comparable to a window unit in power consumption.

What I'm really hoping to hear from people is actual make/models of generators that are around 3500W and have 240V output. I've already got the wattage requirements figured out using hard data.

If you are looking for 240V in that size generator, your best bet would be an older Honda 3500, 3800, or 5000 that have a 240v receptacle. The older Hondas are great generators.

 

[theoldwizard1]

If you look at how Generac Genmax does their "series" connection, you will notice a extra set of wires with a screw lock connection. Very important !!

The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V. The extra wires are there to keep the inverter circuits perfectly synchronized at 180° out of phase with each other. Electronically, with inverter circuits this is quite easy to do. I am surprised it took so long for some company to do it.

Retro-fitting other generators might be possible, but certainly not easy !

 

[dave*99]

If you look at how Generac does their "series" connection, you will notice a extra set of wires with a screw lock connection. Very important !!

The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V. The extra wires are there to keep the inverter circuits perfectly synchronized at 180° out of phase with each other. Electronically, with inverter circuits this is quite easy to do. I am surprised it took so long for some company to do it.

Retro-fitting other generators might be possible, but certainly not easy !

Generac or Genmax? I've seen a Genmax kit to produce 240V from (2) 120V Genmax inverter generators.

GM6000SPK - Parallel Kit

Set Up Precautions 1. Set up and use only on a flat, level, dry, well-ventilated surface.2. All connections and conduits from the Generators to the load must only be installed by trained and licensed electricians, and in compliance with all relevant local, state, and federal electrical codes and...

www.genmaxpower.com

In the Genmax system, when configured to supply 240V, the load is strapped across the inverter outputs putting the generators in series as load current passes through the load and the output circuits of the (2) inverters.

FWIW, I know Generac makes a parallel kit to put 2 inverter generators in parallel to double the current. These are truly in parallel.

https://www.amazon.com/Generac-7118-Parallel-Inverter-Generator/dp/B0716T2NMR/?tag=atomicindus08-20

 

[Mr onetwo]

I bought a WEN. I have not run it yet, but seems a good quality and customer service is in the USA.

WEN DF1100T 11,000/8,300-Watt 120V/240V Dual Fuel Gasoline and Propane Powered Electric Start Portable Generator with Wheel Kit

Switch between gasoline (11,000 surge watts, 8,300 running watt) and propane (9,500 surge, 7,500 running) with the simple turn of the selection dial Voltage easily goes from 120-Volt to 240-Volt, perfect for transfer switches and emergency backup Electric start powers the 457cc 4-stroke OHV...

wenproducts.com

 

[AA/FC]

If you look at how Generac does their "series" connection, you will notice a extra set of wires with a screw lock connection. Very important !!

The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V. The extra wires are there to keep the inverter circuits perfectly synchronized at 180° out of phase with each other. Electronically, with inverter circuits this is quite easy to do. I am surprised it took so long for some company to do it.

Retro-fitting other generators might be possible, but certainly not easy !

It's Genmax

 

[dave*99]

It's Genmax

And they are in series. No quotes needed.

 

[AA/FC]

And they are in series. No quotes needed.

I didn't quote you... (until now)

 

[nadogail]

I bought a 13 Horse Engine from Harbor Freight back when they were selling Greyhound Engines built by Lifan. I is coupled to a 10 KW Chicago Electric Alternator, I think it is good for about an honest 6 KW.
Other than a Lovejoy coupling I had to get a 12 volt starting battery.
Everything else was picked from dumpsters or my Bone Yard.

 

[dave*99]

The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V.

I didn't quote you... (until now)

Sorry for being unclear, I was referring to the quote marks mentioned in the prior post. Since the load connects the generators in series, post 90 contains misinformation.

 

[AA/FC]

Sorry for being unclear, I was referring to the quote marks mentioned in the prior post. Since the load connects the generators in series, post 90 contains misinformation.

Other than getting the manufactures name wrong, what information is he wrong about? Genamx calls this setup "Parrellel & Series", it's printed right on the side of the generator. And if you look at the Amazon listing for the GM6000SPK kit (that you posted above) it says "parallel and series" kit right in the title of the product listing. The kit will truly give you either parallel (double the amperage) OR series (double the voltage) it's just a matter of connecting the additional sync wires to get double the voltage, or NOT connecting the extra sync wires and getting double the amperage. (like a typical parallel kit)

 

[dave*99]

If you look at how Generac does their "series" connection, you will notice a extra set of wires with a screw lock connection. Very important !!

The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V. The extra wires are there to keep the inverter circuits perfectly synchronized at 180° out of phase with each other. Electronically, with inverter circuits this is quite easy to do. I am surprised it took so long for some company to do it.

Retro-fitting other generators might be possible, but certainly not easy !

Other than getting the manufactures name wrong, what information is he wrong about? Genamx calls this setup "Parrellel & Series", it's printed right on the side of the generator. And if you look at the Amazon listing for the GM6000SPK kit (that you posted above) it says "parallel and series" kit right in the title of the product listing. The kit will truly give you either parallel (double the amperage) OR series (double the voltage) it's just a matter of connecting the additional sync wires to get double the voltage, or NOT connecting the extra sync wires and getting double the amperage. (like a typical parallel kit)

You are correct the Genmax does BOTH. I corrected my post.

As for post 90, The part in bold is incorrect. When configured for 240V series operation, it's incorrect to state the generators are NOT in series.

 

[AA/FC]

I don't understand why any company/customer would be willing to spend on fuel injection when today's carbureted engine work well, cost less and meet all current emissions standards.

I remember people saying that same type of thing in the mid 1980's when passenger cars made the switch to electronic fuel injection.

Could you imaging if they still sold brand new cars with carburetors today? I can't either!

A carbureted engine in ONLY tuned correctly when atmospheric conditions and altitude match the fixed jetting in a carburetor. That window is VERY small. The engine is either running rich or lean at all other times..... which is most of the time! A fuel injected engine is (theoretically) running at the optimum air/fuel ratio at ALL times, regardless of altitude or weather/atmospheric conditions. An engine that is running at the proper air/fuel ratio is much more efficient, and will potentially last much longer. Not to mention ease of operation.

I see very few downsides to electronic fuel injection.... Especially in 2024. It's been perfected over the last 40 years.
1. Extra initial cost
2. Extra complexity with electronics.

The extra up front costs could POTENTIALLY be made back in fuel efficiency.... Depending how ****** of a carbureted generator it's compared to. And extra complexity with added electronics is really a non issue considering all these inverter generators are full of electrics that can fail at any time..... a few more electronics to run the fuel system isn't really the end of the world, to me anyway.

 

[AA/FC]

You are correct the Genmax does BOTH. I corrected my post.

As for post 90, The part in bold is incorrect. When configured for 240V series operation, it's incorrect to state the generators are NOT in series.

Gotcha.

 

[mike93lx]

I remember people saying that same type of thing in the mid 1980's when passenger cars made the switch to electronic fuel injection.

Could you imaging if they still sold brand new cars with carburetors today? I can't either!

A carbureted engine in ONLY tuned correctly when atmospheric conditions and altitude match the fixed jetting in a carburetor. That window is VERY small. The engine is either running rich or lean at all other times..... which is most of the time! A fuel injected engine is (theoretically) running at the optimum air/fuel ratio at ALL times, regardless of altitude or weather/atmospheric conditions. An engine that is running at the proper air/fuel ratio is much more efficient, and will potentially last much longer. Not to mention ease of operation.

I see very few downsides to electronic fuel injection.... Especially in 2024. It's been perfected over the last 40 years.
1. Extra initial cost
2. Extra complexity with electronics.

The extra up front costs could POTENTIALLY be made back in fuel efficiency.... Depending how ****** of a carbureted generator it's compared to. And extra complexity with added electronics is really a non issue considering all these inverter generators are full of electrics that can fail at any time..... a few more electronics to run the fuel system isn't really the end of the world, to me anyway.

ABS and seat belts **** too. Duh

I'd love to never buy something with a carb again.

 

[AA/FC]

ABS and seat belts **** too. Duh

I'd love to never buy something with a carb again.

Oh, the list is long! lolol.

 

[imagineer]

Probably commented on already, but don't underestimate your wattage needs.

Our 1st generator was a Porter-Cable 5500 watt (BSV550-W). Whereas it had no problem providing power for my well pump along with a fridge, freezer and handful of lights, the microwave oven brought the portable generator to it's knees.

I later upgraded to a Westinghouse 9.5kW portable (WGen9500) which had no problems running all I threw at it.

Since then, I installed a Generac 24kW running on natural gas & gave the Westinghouse to my son. Our original Porter-Cable is our back up now.

Lastly, if possible, opt for a portable with solid tires. Our Porter-Cable has pneumatic tires and they go flat in 6 months.

 

[theoldwizard1]

I remember people saying that same type of thing in the mid 1980's when passenger cars made the switch to electronic fuel injection.

Could you imaging if they still sold brand new cars with carburetors today?

I was there, writing the software that actually ran those engines !

It was government regulations that forced the use of catalytic converters. Catalytic converters have a very short life if not operated very close to stoichiometry. Feedback carburetor came close, but not close enough.

... a few more electronics to run the fuel system isn't really the end of the world, to me anyway.

It is not the electronics that are $$$, it is the extra parts. At a minimum you need a high pressure fuel pump and an oxygen sensor. Neither are cheap even though millions are made each year.

 

[theoldwizard1]

As for post 90, The part in bold is incorrect. When configured for 240V series operation, it's incorrect to state the generators are NOT in series.

Obviously you do not understand how AC generators work or how "split phase" power is created.

You can not "add" AC power like you can with DC (batteries).

 

[theoldwizard1]

I'd love to never buy something with a carb again.

Not quite the "holy grail" you are making it out to be !

I had a 4 stroke outboard with EFI. There was some fuel in the tank from OVER 18 months. Gummed up the injectors when I started it. You need special equipment to clean injectors (all those injector cleaner products did not work). Cost me more than a couple of bucks to send them out to be cleaned.

 

[dave*99]

Obviously you do not understand how AC generators work or how "split phase" power is created.

You can not "add" AC power like you can with DC (batteries).

Once again you are in over your head when you talk about electricity and electronics.

Split phase power is a perfect example of the series connection to a 240V load. Both poles in the service panel are connected in series with the load. Just as the two inverter generators are with the Genmax system producing 240V.

The phasing cable ensures the inverters operate 180 degrees out of phase. The load current is in series with the output circuits of the inverters.

 

[AA/FC]

I was there, writing the software that actually ran those engines !

It was government regulations that forced the use of catalytic converters. Catalytic converters have a very short life if not operated very close to stoichiometry. Feedback carburetor came close, but not close enough.


It is not the electronics that are $$$, it is the extra parts. At a minimum you need a high pressure fuel pump and an oxygen sensor. Neither are cheap even though millions are made each year.

I never said anything about catalytic converters, that's all in your head....

The Genmax generator with Fuel Injection that I posted earlier in this thread is not much more money than a similar carbureted generator. (IF you could even find a similar 4600 watt generator with series & parallel capabilities that happens to be carbureted) And don't use a Honda as your example.... Honda's are always much more expensive just because of their name. (and reputation)

I just don't see all this extra cost that you're talking about.

If you like carburetor engines so much, feel free to keep using (buying) them. Nobody is stopping you.

People like me will be buying modern equipment with modern technology.

 

[theoldwizard1]

I never said anything about catalytic converters, that's all in your head....

I was working for one of the Detroit Big 3 in the late 70s and early 80s. Where were you !

My main point is that EFI does NOT solve all fuel related problems with gasoline engines

 

[theoldwizard1]

Split phase power is a perfect example of the series connection to a 240V load. Both poles in the service panel are connected in series with the load. Just as the two inverter generators are with the Genmax system producing 240V.

I would disagree with that statement. You make it sound like these are independent sources when in fact they are the same source and a center tapped transformer creates each leg.

The phasing cable ensures the inverters operate 180 degrees out of phase.

I think I said that before !

 

[dave*99]

I would disagree with that statement. You make it sound like these are independent sources when in fact they are the same source and a center tapped transformer creates each leg.

That is your misinterpretation. What is the significance of the center tap in the case of a 240V load on that transformer? It certainly ensures each leg remains at 120V above ground, but there is no current flow in the center tap from the 240V load. Each leg will be there whether the center tap exists or not. Just don't try to connect a 120V load.

This is your statement in post 90:
The reason I put series in quotes, is because the generators are NOT really in series ! Each generator is supplying one leg of the 240V.

Tell us how a load connected ACROSS the outputs of 2 inverter generators is not a series connection.

Current passes serially through both inverter outputs and the load. Why do you state the generators are not in series? The statement that each generator supplies one leg contradicts the statement that they don't form a series circuit with the load. This is really basic stuff.

 

[AA/FC]

I was working for one of the Detroit Big 3 in the late 70s and early 80s. Where were you !

My main point is that EFI does NOT solve all fuel related problems with gasoline engines

No I wasn't and that still has nothing to do with catalytic converters. You asked why people would buy a fuel injected generator these days when carbs still work fine. I gave you my reasoning. Then YOU came back talking about cat conveters, NOT me. I never once mentioned catalytic converters. Congrats on your job with the big three

Nobody said FI solved ALL problems. Anyone who is still using ethanol fuel in their small gas engines in 2024 is either content with cleaning clogged fuel systems, or completely oblivious to the problems with ethanol. (if these are the problems you're talking about) I haven't used a drop of ethanol in ANY of my small gas equipment (and I have many small gas engine powered machines) since about 2011 or 2012. I have not had ONE SINGLE problem with any of my machines since day one of using non-ethanol. Half my equipment sits during the winter, and the other half sits during the summer. All my stuff starts and runs perfectly fine after sitting for 6-9 months, every year.

 

[theoldwizard1]

No I wasn't and that still has nothing to do with catalytic converters. You asked why people would buy a fuel injected generator these days when carbs still work fine. I gave you my reasoning. Then YOU came back talking about cat conveters, NOT me. I never once mentioned catalytic converters. Congrats on your job with the big three

Catalytic converters (the only way to meet government exhaust emission standards) is THE ONLY REASON all cars since the 1980s have EFI ! They would still be using carburetors is they could.

 

[theoldwizard1]

I haven't used a drop of ethanol in ANY of my small gas equipment (and I have many small gas engine powered machines) since about 2011 or 2012. I have not had ONE SINGLE problem with any of my machines since day one of using non-ethanol. Half my equipment sits during the winter, and the other half sits during the summer. All my stuff starts and runs perfectly fine after sitting for 6-9 months, every year.

I use E10 on all of my power equipment. Never a problem.

"an ounce of prevention is worth a pound of cure !". All of my equipment has a fuel shut off and before storage, I run the carb dry.

 

[AA/FC]

Catalytic converters (the only way to meet government exhaust emission standards) is THE ONLY REASON all cars since the 1980s have EFI ! They would still be using carburetors is they could.

You honestly think brand new cars would still be using carburetors in 2024 if catalytic converters were not made mandatory is the 1980s???

You honestly think THE ONLY reason to use electronic fuel injection on gasoline engines is BECAUSE catalytic converters can't handle carburetors??? That right there should tell you just how bad (inefficient) carburetors are.

Here's a scenario for you.... Let's just say the US government suddenly did away with pollution laws and catalytic converters were no longer mandatory.... Do you really think car manufacturers would go back to using carburetors in 2024? (you typed it in your reply above, not me)

I can think of a MANY reasons why fuel injection is far superior and none of them have to do with catalytic converters. Cats may have been the original reason for FI, but now that it's perfected, nobody is going back to carbs..... except maybe you. And that's okay, enjoy your carburetors. lol.

 

[AA/FC]

(That reminds me. Time to exercise my generator ! Probably should drain its tank and add fresh E10 !!)

I use E10 on all of my power equipment. Never a problem.

"an ounce of prevention is worth a pound of cure !". All of my equipment has a fuel shut off and before storage, I run the carb dry.

On March 6th you replied to my original post in this thread (post #83) and you mentioned having to drain your generator tank and add fresh E10. (see your quote at the top of this post) Then today you come back and tell us that you've never had a problem using E10. lolol

I have never needed to drain any of my fuel tanks because I use straight gasoline. I have non-ethanol gas in my big snow blower that is at least 1.5 years old, maybe two years old right now. I only used it once this winter (we had almost no snow) and it fired right up and ran perfectly. I will leave that gas in the snowblower and it will run perfect again next year, too. No draining tanks here.

 

[AA/FC]

delete

 

[mike93lx]

You honestly think brand new cars would still be using carburetors in 2024 if catalytic converters were not made mandatory is the 1980s???

You honestly think THE ONLY reason to use electronic fuel injection on gasoline engines is BECAUSE catalytic converters can't handle carburetors??? That right there should tell you just how bad (inefficient) carburetors are.

Here's a scenario for you.... Let's just say the US government suddenly did away with pollution laws and catalytic converters were no longer mandatory.... Do you really think car manufacturers would go back to using carburetors in 2024? (you typed it in your reply above, not me)

I can think of a MANY reasons why fuel injection is far superior and none of them have to do with catalytic converters. Cats may have been the original reason for FI, but now that it's perfected, nobody is going back to carbs..... except maybe you. And that's okay, enjoy your carburetors. lol.

Arguing with the wall

 

[AA/FC]

Arguing with the wall

I know....