rewiring a portable generator

speedster1

I have a champion 4000/3500 watt generator I bought form Cabelas a year or so ago. http://www.championpowerequipment.com/generators/46516/

At the time of purchase Cabelas advertised this generator as 120/240 at 30A. My plan was to backfeed my electrical panel (with an interlock kit) just so that I could power my fridge and a few lights during a power outage. The generator sat in it's box for months before I finally took it out and inspected it. What I found was that the generator didn't support 240V. I was pissed and called Cabelas. Their service was horrible. I asked if I could return it and they said no. They said I had to deal with Champion. However, within a day they had their site updated and removed the 240V information on the generators webpage.

So now I'm stuck with a generator that can't be used to backfeed a circuit breaker.

I did correspond with the Champion folks and they were quite nice. They told me the model I purchased operates in parallel. It has 2 -120 volt windings that are stacked to get high amperage at 120 volt. Separating the windings will give 2-120 volt hot legs (2x120=240 volt) that can be re-wired by someone who’s handy. An additional breaker would need to be installed and also the L14-30 receptacle. They said at 240 the gen would have 16.6 amps at start up and 14.6 amps running.

I know that isn't many available amps. But I'm really just concerned with the fridge and a few CFL lights.

Anyone have ideas how accomplish this?

bubbler

I've got the same generator, and I have heard people talk about re-wiring it to 240V.

Actually it looks more complicated then you'd think...

Here is the 240V version, Page 20 has the schematic:
http://www.championpowerequipment.co...al-english.pdf

Here is the 120V version, Page 21 has the schematic:
http://www.championpowerequipment.co...al-english.pdf

You'll have to get two 15A circuit breakers in there (the 120V version has a 25A breaker)

You'll have to split apart the two windings... MW1 and MW2 are wired in parallel on the 120V version, they need to separated.

There is some sort of a terminal block or something shown on the 240V version which doesn't exist on the 120V version...

Of course you'll void your warranty, and if something does go wrong with it you may look like you are at fault due to modifying it...

I don't know what you paid for it--and not to rub salt in the wound--but I hope it wasn't $330 Cabela's is looking for it... I got mine shipped to my door for $255 from Advance Auto in June of last year...

For now I bought a breakout 25' cable which plugs directly into the L5-30R, it's a 10 gauge cord, and it breaks out into (3) standard 120V receptacles. From there I run (3) #12 cords in the house... one to kitchen, one the bedroom (or living room) and one to furnace area.

__________________
My advice is based on anecdotal knowledge or personal experience. I'm not a professional no matter how matter of factly I may say something
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

micromind

This can indeed be done.

Depending on how it's configured, you'll likely find 4 wires coming from the stator. If it has a single pole circuit breaker, two will likely go to one side of the breaker, the other two would go to one side of the receptacle.

If this is the case, label one of the wires on the breaker #1. Label the other one #3. Label one of the wires on the receptacle #2. Label the other one #4.

Now, disconnect all 4 wires. Splice #2 and #3. Start the engine and measure voltage between #1 and #4. If it's 0 volts, swap #1 and #2 and relabel them. Now you should have 240 between #1 (formerly #2) and #4.

If so, the splice (#2 and #3) is the neutral, #1 is one of the hots and #4 is the other hot.

bubbler

This is the break out cord I got...

http://www.amazon.com/Coleman-Cable-...f=pd_sim_lg_17

__________________
My advice is based on anecdotal knowledge or personal experience. I'm not a professional no matter how matter of factly I may say something
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Oso954

Why can't you use the generator to backfeed a single 30amp phase of 120V ?
You would only have use of the lights on that phase, but a couple of lighting circuits could be swapped if you needed to get the lights for a certain area on the hot phase.

Reliance Controls makes transfer switches for 120V feed.

As far as producing 240V from that generator, I don't think it will give you what you are looking for. Those two windings should be running at the same phase angle if they are paralleled. If you put them in series, you will end up with 240V on a single phase (European style). American style 240V is 2 phases of 120V, 180 degrees apart.

insaneirish

Residential power in the US is produced from a single phase. A single phase goes into a transformer whose center tap is grounded and becomes what we think of as a neutral. The most common name for this setup is split phase. It is not two phase.

By taking two windings on the generator and putting them in series, you are effectively just creating a larger secondary winding and increasing the voltage. By then tapping the junction at which you join the two windings, you are center tapping it, creating what we consider to be a neutral. This is akin to what the step down transformer powering your house does.

If you look at the difference between the generator schematics, the 240V version is doing exactly that.

biggles

what is the model on that generator? do you have a 115V outlet and a 240V oulet or jusr 2-115V ones....

bubbler

Biggles this generator is 120V only. Not 240V.

It has an L5-30R, an RV plug (a 7-50R I think) and a standard 5-20R (like you'd find on your wall).

It is not setup 240V. The OP is asking how to re-wire the generator to be 240V.

__________________
My advice is based on anecdotal knowledge or personal experience. I'm not a professional no matter how matter of factly I may say something
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

speedster1

I've been told I could backfeed a single 30A breaker in my panel and it would effectively let me use any of the breakers on whatever side of the panel I'm backfeeding. At this point I could optimize how i install my new panel making sure that the fridge and the most important light circuits are on the same side of the box. I guess thats certainly an option. I'd prefer to have the ability to access all circuits in the load center.

Maybe I should just look into selling this generator and getting another one that can handle it. My curiousity has me wondering how difficult it would be to accomplish this. Sounds easy enough for you electricians but maybe a little more than I should tackle. I'd probably do it if I had a step by step instructions or video.

Anyone have recommendations on a low cost generator that would supply my 240V needs?

insaneirish

Harbor Freight has some.

bubbler

Define "low cost"?

The Champion 46514 (the 240V version of what you have) is basically the same price as the 120V version... ~$330 from Cabelas, etc. Depending on what you could get for yours, you might only be out $100 or so?

Or, if you had some add'l money, and wanted a better solution, you could go up to a larger generator like the Champion 41332 (http://www.championpowerequipment.com/generators/41332/) ... Costco sells them (in stock usually) for $600 I believe? They're 6500 running watts (almost double the 3500 from your current one), they're also electric start and REMOTE start... what this means is that if you know you've got a power outage likely, due to a storm, you can get yourself setup to go ahead of time... then if the power goes out, you push a button, generator starts, you flip the interlock, and you're all set... no need go out in the weather. Same goes for mornings and evenings... you don't have to go outside to shut it down for the night--just flip off the generator breaker off in the panel to take the load off, then hit the button to shut the generator down...

I have two friends who ended up buy the 41332 a few months after I had bought mine... in hindsight I wish I had bought it instead of the one I got because since buying it I swapped over to an electric tank water heater... so I have no hot water in an extended power outage at the moment, where as if I had the larger generator I could.

__________________
My advice is based on anecdotal knowledge or personal experience. I'm not a professional no matter how matter of factly I may say something
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

theatretch85

Do you actually have any 240 volt loads that you need/want to power with the generator? Or are they all 120 volt? Might be able to jumper the single 120 volt hot to two poles of a double pole breaker, it'd feed both busses in the panel, just would not power any 240 volt loads. Of course you'd certainly want to make sure you have a interlock kit on your panel before doing this!

speedster1

In all honesty there are no 220V loads in my home. My dryer, hot water, and stove are all gas. My Furnace blower is 110V. My reasoning for wanting 220 was to power both rails. If I could setup a jumper to energize both rails that would suffice. But is a code violation? Would this be accomplished by adding a two 30A single pole breaker below a 30A double pole and feeding one of the 30A breakers from the generator and connecting the other 30A single to the second pole of the double pole? I can't imagine this being up to code.

theatretch85

I'd just wire it to both poles of a double pole breaker. Again, make sure you have an interlock kit on the panel, flipping this breaker on while the main breaker is on would create quite the light show in your breaker panel.

micromind

Imagine what would happen if the jumper that energizes both poles were to be in the circuit while the utility power was on......

The only legal way to backfeed a panel with a generator is to make it physically impossible for both the utility and generator breakers to be on at the same time.

Rob