Generator Question

[Mrwurm]

Hello folks, in desperation I purchased this generator at HomeDepot because it was the only thing in stock for many miles around (Ice storm). My question is this. Will the 30amp 240 outlet supply ALL the power that the generator is capable of? Some of the higher-end generators have a 240 outlet and another 240 outlet that is labled "Full Power". I have heard some chatter that on these lower-end machine only half of the wattage is available at the 240 outlet. Any comments are welcome. I am not opposed to returning this item and buying a better unit if I can find one.

 

[tc35dforme]

Well, 5500 watts at 240 volts is about 22.9 amps. Seems that a 30 amp plug and circuit should handle it okay. That's what I run. Similar unit but bought at a wholesale club. Internally, the unit is most likely wired to feed the 240 volt and 120 volt circuits in parallel or together. They don't split part of the power to one set and part to the other. I don't think anyway.

 

[gerard]

Seems to be a pretty big spread between the continuous output (5500watts) and the surge (8kw). I have an 8kw generator that puts out 6600 continuous and it has the same 240 plug configuration as that shown in the site you linked. I just use that to feed my whole house with no problem. I run oil heat, well pump, refrig, separate freezer, sump pump, and pond pump and nhaven't run out of juice yet. (Did trip breaker when wife turned on all the arena lights which draw over 1500 watts alone on one leg). If you have the option I'd consider looking for one with a honda motor. Tough to beat. I just stopped in the local hardware store and he was repairing a bunch of generators - none had a honda motor /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif I figured when all I see are honda's on commercial equipment there must be something to it /forums/images/graemlins/smile.gif

 

[Egon]

Chances are the amperage and wattage have been confused. The 240 volt will produce 1/2 the amperage of the 120 volt outlet. All it means is that there is less line power loss in the form of line resistance with the 220 as compared to 110. Wattage will still remain the same.
Egon

 

[Mrwurm]

I'm with you on the Honda motors but everything is sold out due to the massive power outages that continue from last fridays ice storm.
So, does anyone know why the higher-end Generac units have two 240 outlets, one labled 240 at XXamps and the other labled 'Full Power'. What's the difference?

 

[gerard]

Just an educated guess here but if you use the "non full power" one you may also be able to use the 110 volt outlets also without drawing down the full capacity? In other words if you're going to backfeed a panel and want the whole capacity of the generator available you would use the full power outlet but if you were out at a worksite and wanted to use the 240 volt for one thing and still use some of the 110 circuits you would use the other one??

 

[Mrwurm]

I posted this same question in another thread, but in case you did not see it, here it is again.

What does a transfer switch do for you. I know it is not recommended but most everyone that I know sets up their generator in the following way:
1) Turn off main breaker at house panel.
2) Wire up a heavy cord with two male ends. (240 V)
3) Plug one end of cord into a household 220 outlet.
4) Plug other end of cord into generator 220 outlet.

I have done it this way and had no problems. I even ran a few hours this way when the power was restored before I knew it had been restored.

When operating the generator this way, I switch on only the individual breakers that I want to power and I shut off the rest.

I plan to install a main disconnect between my meter and my house panel to provide a larger airgap between the terminals. This should greatly reduce the risk of arcing between the contacts on the main breaker.

I am using my limited experience to make this assumptions. Please advise and explain if I should do something different.

 

[Anonymous Poster]

A transfer switch prevents you from inadvertently connecting your generator to the power grid, which would almost assuredly have nasty results, and could possibly prove fatal to someone.

I can't imagine it not being a code requirement wherever you are located.

You are substituting fallible human judgement for a properly engineered projective device, which is usually a poor idea. Sorry to be so blunt, but I don't know any other way to put it.

SnowRidge

 

[Anonymous Poster]

The problem isn't necessarily that you might make a mistake and throw the wrong switch at the wrong time, but if you are not home and your wife or someone who isn't familiar with your system tries to switch it over.
I've worked with electricity for Xrfmbv(sp) years and am comfortable wiring in my generator when I need it, but my wife would have no clue how to hook it up or unhook it. And I only have one neighbor who I would trust. If I'm not home my wife is SOL.
I should hook it up the right way too but I'm known to be cheap from time to time and haven't spent the money to do it yet.
/forums/images/graemlins/grin.gif

 

[skent]

Not to fault what you are doing, but a neighbor had one happen years ago - Thunderstorm lightening strike took out the local grid, he shut off the main and plugged in a male to male with his generator.
Things were going ok until the next close strike. A spike traveled back through the neutral (called a commom mode spike) and took out his generator.
In this case, an inexpensive transfer switch would not have helped since they normally use a shared neutral and ground.

What I have done with my system is to install "generator only" outlets where I need the power, by the refrig, freezer, even put the well pump on a plug with two outlets - one on the grid, one on the generator. Generator outlets are marked with a glow in the dark star.

In the event of a power failure, I start the generator, and plug those things I wan running into generator outlets. All tied to a seperate-from-the-grid dedicated ground. When power is restored, I shut off the generator and plug back into grid.