generator extension cord

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I need to make a short extension cord that goes from my portable generator 240V 4-wire receptacle to a 3-wire receptacle that powers 2 120V house circuits. The 3-wires are red and black and white. How do I make this? The 3 wires go into a junction box where the white wire is attached to some kind of common connection and the red and black are each attached to its own toggle switch that flips the power between the power company and the generator.
TIA
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On Jun 13, 4:58 pm, "mike snipped-for-privacy@hotmail.com"

You get Transfer panel so its all a safe no brainer, no overload, no death, no refusal to reconnect, its balanced. maybe 200$ at Lowes prewired and labeled and 2 - 5 hrs work
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Your little circuit doesn't have a ground? That is pretty idiotic; I would recommend against using it. Who knows what else is done improperly.
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Furthermore, backfeeding a house circuit through an outlet is about the stupidest thing you can do. If it only affected your house, I'd say go for it and what what happens when your insurance company refuses to pay out any claims. Seeing the legal prosecution for endangering emergency workers would also be fun if it wasn't for the potential threat to their life.
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wrote:

Backfeeding your house with a generator is a wise thing to do if you have a transfer switch.
It is dangerous, without one, for many reasons.
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You need to read a bit closer. I said that backfeeding a house _through an outlet_ is about the stupidest thing you can do. There is no way to wire a transfer switch into an outlet.
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Dottie wrote: ...

But in all likelihood, correctly done.
Plus, the dude will know what he's doing; OP obviously doesn't (nothing wrong about that other than trying to get by w/o getting proper input) and his description makes it sound like he's got a questionable arrangement at best...
--
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Here is a link to some pictures of the configuration:
http://home-and-garden.webshots.com/album/563794165CXmatm?vhost=home-and-garden
It is as simple as getting the proper 120/240 plug and wire and using the ground screw in the connection box to connect the ground wire coming from the plug? The red and black will be hoy and the white will be neutral.
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mike snipped-for-privacy@hotmail.com wrote: ...

OK, neater than I expected but still a problem possibly.
Problem diagnosing from afar is can't tell what's in the box the two toggle switches are switching.
The box itself appears to simply be a junction box, not a commercial transfer switch so can't assume anything about what is actually inside.
The labels say "ATS" which one would infer stands for "automatic transfer switch" but don't know if that's what's behind them or not, nor what they're actually switching.
If they are the two hot legs, they're not supposed to be independently switchable. If there is some control logic inside for an auto-transfer mode, it's remotely possible it is compliant.
I still think if you are unable to tell for sure what you're looking at if you open it up (which I presume is the case or you wouldn't be asking the kinds of questions you are), you should have a licensed electrician or the power-co look at it before it is used.
Note this doesn't mean it doesn't "work" -- it simply isn't clear what the installation actually does and whether it is compliant w/ the Code and rules for ensuring disconnecting from the grid are being followed.
--
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wrote:

Here is a link to some pictures of the configuration:
http://home-and-garden.webshots.com/album/563794165CXmatm?vhost=home-and-garden
It is as simple as getting the proper 120/240 plug and wire and using the ground screw in the connection box to connect the ground wire coming from the plug? The red and black will be hoy and the white will be neutral.
Mike, you have some very nice pictures, but I am unable to tell how everything is wired to each other. However from what I did observe, this is not a code compliant installation. There is non-metallic (Smurf tube) being used outdoors and in the ground and also without the proper fittings. There are exposed conductors without conduit going from the circuit breaker panel to the homemade transfer switch box. I am guessing that the grey fused switch (Junction box) is protecting the generator load, but the wires inside seem to be several different sizes. This entire installation seems more complicated then it needs to be.
I strongly suggest that you have an electrician go over this and bring it up to code.
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linemen working on dead lines are SUPPOSED to install short jumpers, in case someone accidently throws the wrong switch somewhere.
Like everything people arent perfect, linemen make mistakes
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On Sat, 14 Jun 2008 12:37:24 -0700 (PDT), "mike snipped-for-privacy@hotmail.com"

It looks like the original owner had the generator cord "hard wired" into the box. He also failed to use a weatherproof connector. It should be one of these. http://tinyurl.com/4k23rs
You could also hard wire a cord, or you could mount an inlet box. http://tinyurl.com/3uky6o You can't use the existing box for an inlet box because the plug is too big to fit in a single gang box.
The cord you need is 10/3 SO cord. Because of the possibility of fire, you should not put the generator too close to the house, but you also don't want the cord any longer than necessary. I would go with 10 feet.
It needs a NEMA 10-30R on the generator end and either hard wire it into the box or use a NEMA 10-30P for the inlet end.
You have to ground the frame of the generator to either the house ground rod or a separate ground rod.
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wrote:

Actually you are correct. You have to use an "inlet"
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Isn't the transfer the box that has the 2 toggle switches to switch between power company and generator? Everything was already in place and working when I bought the house. The only thing missing was how the generator hooked up to the 3-wires going to the sub-panel. What ever contraption the previous owner used to connect his generator to the end of the 3 wires is missing and a mystery to me. I am pretty certain that whatever he did was correct. I just don't know what he used to go from 4 wires to 3 wires.
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On Fri, 13 Jun 2008 16:26:09 -0700 (PDT), "mike snipped-for-privacy@hotmail.com"

This is the proper cord.
http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId051&langId=-1&catalogId053&productId0428047
You can safely make one for a lot less.
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On Jun 13, 5:58�pm, "mike snipped-for-privacy@hotmail.com"

did you know some main service breaker boxes support a either normal or emergency mode lock out, which safely backfeeds your home and prevents accidently powering the power companies lines
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I think that the best thing to do at this point is to provide a link to pictures of the configuration. I will work on this today. I believe the installation was done professionally and the solution is simple but I just do not have the resources beyond asking for help here. Thanks for everyones input.
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mike snipped-for-privacy@hotmail.com wrote: ...

It would undoubtedly help, but I have a pretty good idea what you'll show will be a jury-rigged setup that isn't proper.
If you don't have the resources to get an electrician to inspect as someone else suggested, I think you should simply not attempt to use the generator until you can do so.
Unless it is approved (and I seriously doubt the arrangement you have described is or has been), you cannot legally hook it up anyway in any jurisdiction. The danger of "backfeeding" thru your service transformer to a utility worker the high voltage on the other side of the transformer is simply unacceptable w/o a a _PROPER_ transfer switch arrangement (and two toggle switches ain't proper).
The fact the former owner apparently didn't even connect the ground is a problem and shouldn't use w/o it, but it pales in comparison to the other as severity of risk.
--
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On Sat, 14 Jun 2008 08:07:30 -0700 (PDT), "mike snipped-for-privacy@hotmail.com"

Take pictures of what you have. And/or the voltage and current ratings of the plugs
Post them to tinypic.com, then post the links here.
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The first thing that tells me the installation was NOT professional is the collection of individual wires that leave the bottom of the "transfer switch", the center bunch have a short length of flexible plastic conduit that doesn't go all the way to the breaker box and it is attached to the box with the wrong type of connector. They ALL should be enclosed in conduit or other approved sheath.
The second thing, is that all the Romex cables are strung loose and not attached to the studs as they are required.
The third thing, is the homemade "transfer box" with the Dymo type labels that is made out of an electrical junction box. Toggle switches do not usually have the capacity for a 5kw generator, provide no separation between generator and utility power and don't provide forced disconnect of one source before connecting to another power source. Plus each hot leg of the circuit is switched separately instead of being tied together. In some areas the neutral needs to be switched as well.
Install a proper legal transfer switch according to the NEC code and be safe.
wrote:

I think that the best thing to do at this point is to provide a link to pictures of the configuration. I will work on this today. I believe the installation was done professionally and the solution is simple but I just do not have the resources beyond asking for help here. Thanks for everyones input.
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