powering split phase from a 120v generator

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Raventai

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Hello, I am an electrician but not this kind of electrician. I live in Florida and every year we lose power for a week or more, this year I bought a 2200 watt 120v Honda generator. It's quiet sips fuel and will power my essential loads, refrigerator, tv, internet, LED lights. Cell phones And a small fan.

Now I could snake extension cords through the house but that's annoying when my house is already wired.

My idea is to place the generator in an existing shed with an existing sub panel, turn off the main breaker to prevent back feeding the electrical grid. Turn off all the 220v breakers and feed in the generator power on both line 1 and line 2 this should propagate to all 120 volt outlets. I plan to do this by placing 2 regular recepticles in the shed each on separate breakers and making double male extension cords that plug into the generator outlets and the two outlets on the sub panel.

Anybody see a problem with this arrangement having the same voltage on the two phasses? Obviously 220 loads cannot be used.

My biggest concern is being safe around the double male extension cords they are a shock hazard if one of the 4 ends becomes unplugged. Otherwise I think it is safe, my ground and neutral are still connected, circuit breakers should still protect as normal,

Another way I have thought about is a single double male extension cord and a 20A 240v breaker with it's outputs jumpered together. That breaker off course would remain off when on "shore power"

So let me have it why is this a bad idea?
 
I'm not sure that anyone here will endorse the lack of interlocks and use of suicide cords. That said, I bet a majority of us electricians would do it in our own homes and not admit to it ;) :angel:
 
Raventai said:
. . . turn off the main breaker to prevent back feeding the electrical grid.

. . . making double male extension cords that plug into the generator outlets and the two outlets on the sub panel.

. . . a single double male extension cord and a 20A 240v breaker with it's outputs jumpered together.

So let me have it why is this a bad idea?
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Each of the above are not only bad ideas, but illegal. Don't do them, please!

Yes, strictly electrically-speaking, what you propose can work, but describes what separates professional electricians from D-I-Y homeowners. Frankly, I'm surprised the forum moderators allowed your post to remain, but I'm glad since it means you can read our responses. A cord could become unplugged by a child, someone may attempt to use your set-up without your supervision, and it would be easy to forget to throw the main during a power outage.

The only proper, safe, and legal way is to use an interlock and an added generator breaker in the main panel that physically prevents the main and generator breakers from being on at the same time. You should also use a house-mounted inlet and a male-to-female cord rather than receptacles and male-to-male cords. You can use suitable cord ends that allow the cord to adapt for any mismatch of configuration between the generator outlet and the inlet.

Remember that utility transformers work both ways, and an accidental back-feed could electrocute a lineman trying to restore the very power outage that caused you to want to use your generator to begin with. I recommend an interlock from https://www.interlockkit.com/ and a real inlet with a twist-lock. You can use a 240v inlet and join the two line conductors in your home-made cord, or use a 120v inlet and join the lines at the generator breaker.
 
electrofelon said:
I'm not sure that anyone here will endorse the lack of interlocks and use of suicide cords. That said, I bet a majority of us electricians would do it in our own homes and not admit to it ;) :angel:
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"We professionals know how to break the rules correctly." :cool:
 
Yes it's a bad idea and there is no reason to cut corners when the proper equipment is available and not very expensive. In an emergency situation making due with what you have can be OK but when we're talking about something that will provide power for a week or more then my advice is do the job right.
 
LarryFine said:
Each of the above are not only bad ideas, but illegal. Don't do them, please!


The only proper, safe, and legal way is to use an interlock and an added generator breaker in the main panel that physically prevents the main and generator breakers from being on at the same time. You should also use a house-mounted inlet and a male-to-female cord rather than receptacles and male-to-male cords. You can use suitable cord ends that allow the cord to adapt for any mismatch of configuration between the generator outlet and the inlet.
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Totally agree! You can jump out the phases. That's ok.
as far as turning off the main before turning on the generator.... or vice versa, I thought the same thing until I turned on the main and the genset was still plugged up with my male to male cord. I didn't destroy my genset but I learned to get it wired correctly.
 
electrofelon said:
I'm not sure that anyone here will endorse the lack of interlocks and use of suicide cords. That said, I bet a majority of us electricians would do it in our own homes and not admit to it ;) :angel:
Click to expand...

When people ask me about how to use suicide cords to save cost of transfer switch

I first determine if they are qualified

If they have to ask, they are not qualified
 
readydave8 said:
When people ask me about how to use suicide cords to save cost of transfer switch

I first determine if they are qualified

If they have to ask, they are not qualified
Click to expand...

My idea for a cheap transfer switch for a single load (such as 240V well pump) is to connect the POCO (downstream of service disconnect) and the generator inlet in parallel to the load using two A/C type fused disconnects with the pull-out fuse holder block. Then take out one of the two pull out blocks and archive it somewhere.
The remaining block can either be placed in the POCO feed or the generator feed disconnect. Clearly only one can be connected at a time.

Not exactly the intended use of the disconnects, but I do not see a clear code violation.
 
It is most temping to do something dirty when you have say a detached garage that has power and is a convenient place to keep the generator= no easy way to interlock the utility and generator supplies. Did one recently, which was a job so I had to do it right, where I ended up mounting the inlet box on the house and made up a long enough cord to get to the garage, so the HO didnt have to move the generator around.
 
I suppose you could go with a kirk key style interlock for the various breakers.

Probably cost more than the generator in a residential application :)

-Jon
 
electrofelon said:
It is most temping to do something dirty when you have say a detached garage that has power and is a convenient place to keep the generator= no easy way to interlock the utility and generator supplies. Did one recently, which was a job so I had to do it right, where I ended up mounting the inlet box on the house and made up a long enough cord to get to the garage, so the HO didnt have to move the generator around.
Click to expand...

Exactly how mine is wired.
 
I do like the idea of a dedicated male outlet that gets me away from the double male suicide cord and it could be mounted at a high in the shed, it's still a bit of a hazard if the generator breaker is on when main power is on but it could be behind a flip cover.


The site is not conducive to a transfer switch. The overhead lines terminate to a power pole, similar to a construction pole used in other areas. The buildings on the property and two Wells are fred from there via buried cables. To properly have lighting through the entire property the transfer would have to happen on the power pole and be sized to disconnect the 200A service, that's an expensive switch and a lot of trenching. More than the cost of the generator.
 
Raventai said:
I do like the idea of a dedicated male outlet that gets me away from the double male suicide cord and it could be mounted at a high in the shed, it's still a bit of a hazard if the generator breaker is on when main power is on but it could be behind a flip cover.


The site is not conducive to a transfer switch. The overhead lines terminate to a power pole, similar to a construction pole used in other areas. The buildings on the property and two Wells are fred from there via buried cables. To properly have lighting through the entire property the transfer would have to happen on the power pole and be sized to disconnect the 200A service, that's an expensive switch and a lot of trenching. More than the cost of the generator.
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You know, you can have more than one transfer switch connected to the same generator. I don't know if this helps you, though.
 
Sorry, but this thread is too DIYer so it's time to close.

Roger
 
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