“Back feeding” generator to breaker box

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I know this isn’t to code and can be dangerous but I believe my approach will work safely until I’m ready for a more permanent system

I have 150 amp service into a Cutler Hammer box with 2 hot busbars running parallel from top to bottom

I’ve added a 20 amp breaker to the each of the busbars using 10 gauge

Each of these are being fed into a 2 pole 30 amp service interrupt

From the service interrupt, I’ll run 10 gauge out thru the wall to a 4 prong outlet

I have a powermate 7,500/6,000 watt generator and will use a 30’ power cord

I’ve been doing this with loose wire since Sandy but I simply fastened the wires direct to the busbars. The above will backfeed in the same way but save me the trouble of attaching the wires

I always shut main service off and all breakers. Attach the wires, start the generator and then, very selectively, turn on breakers as needed: Kitchen lights, WiFi, .... we draw very little at any one time.

Gas heat, oven and hot water so, if I need heat, run only the pump on boiler

So my question:

I have 2 runs of 10/2 coming out of the service interrupt. I want to run these to the exterior outlet which will accept a 4 prong

I have 2 commons, 2 grounds and 2 hot.

How do I wire the outlet? Just pigtail as needed?

Thank you for any input
 
This seems a little foolish to me, although I will admit that I don't know what you mean by "2 pole 30 amp service interrupt". What you need is a transfer switch wired to specific circuits. There is simply no way that should ever wire your generator directly to the bus bars; to do that you MUST go thru a full service transfer switch rated to at least your your service level.
 
Originally Posted By: Astro_Guy
This seems a little foolish to me, although I will admit that I don't know what you mean by "2 pole 30 amp service interrupt". What you need is a transfer switch wired to specific circuits. There is simply no way that should ever wire your generator directly to the bus bars; to do that you MUST go thru a full service transfer switch rated to at least your your service level.


I hear you but here’s my thought process:

The 2 pole service interrupt is nothing more than a cut-off with a 30 amp fuse

At no time will I be drawing more than 15 amps (my fridge)

The lights, WiFi and tv are negligible

The largest circuit in the box is 20 amp.... granted a 30 amp 2 pole for AC but I’d never use it

With the generator isolated, my service level is 30 amps. My interrupt is 30 amps. My max usage if 15 amps

Let me try it another way:

A transfer switch is used to provide juice to 4, 6,.... circuits you want juiced. They are run from the same breaker to the switch and, once the switch is turned on, the main is, at the same time, cut off via that plate

What I’m doing is, in lieu of the transfer switch, I have 2 breakers connected to the box, which feed to my interrupt/cutoff

Instead of having 4, 6, ... dedicated breakers, I pick and choose

The only difference, as I see it, is I simply don’t have the safety protocol whereby the the main for transfer automatically cuts off main from service. I have to do it manually

What am I missing

...understood about the homeowners insurance
 
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Nobody reputable is going to tell you how to do this. It is extremely dangerous on several fronts if you forget to open the main breaker. A transfer switch is designed to be absolutely fail safe against both operator error and equipment failure.

As someone else noted, you can put a large transfer switch between the electric meter and the main breaker. This gives you the flexibility to energize any circuit, subject of course to not overloading the generator. Overloading the generator is actually the least of your concerns here.
 
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Burn your house down if you must... .but please don't kill the lineman with the power company, who is working on the pole out by the road.
 
Buy the $50 kit and do it right? The correct answer is so easy a cave man could come up with it.

And most folks back-feed through the dryer 220 outlet.
 
The right way (depending on local code approval) is this:
https://www.interlockkit.com
A breaker interlock kit that installs in your panel so the main will always be off before the breaker from the generator is closed.

This is the only safe way without an external circuit based or service based transfer switch.

I just run extension cords to run what I need. I only have a 120V generator so I can't power 240v Loads anyway.

When I replace my panel I will get one with an interlock kit for transfer.

Be safe!
 
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To the OP, I found an incoming main/generator transfer switch rated at 200 amps for the main and 50 amps for the generator for $114 on e-bay a couple of years ago. I have not looked at the availability lately but you might check e-bay.
 
Get one of these (Generator Interlock Kit) and be done with it

s-l1000.jpg
 
Absolutely do not backfeed your generator into your electrical system. Much at stake here including the safety of lineman. Get an interlock or transfer switch please. My next door neighbor almost caught his house on fire doing something like you. Generator interlock kits are inexpensive and makes all safe.
 
If you're going to do this, notify your power company because you could kill one of their workers.
 
Originally Posted By: Reddy45
If you're going to do this, notify your power company because you could kill one of their workers.


That's what I was thinking. You'll power lines from your generator that have the main power shut off to them and endanger the workers.
 
When I was preparing to do this, I ran across something that stated that any interlock device must be manufactured by the same company that made the breaker box. I'd guess that is one way to guarantee proper operation and testing and prevent generic junk from being used. Fortunately, there is a Square D device made for my (Square D) box and it works well. I made a point of taping the info card that came with the interlock kit to the outside of the box and installed all of the warning stickers at the box and my outdoor twistlock box.

BTW, I have a neighbor who is a lineman for the local electrical company. I was talking to him about it and he said that whenever they work in a residential outage and there is/are generators running, they'll often pull the meter to be 100% safe then replace it when power is restored (although I've never seen them do so in any of numerous outages we've experienced over the years).
 
I have never seen them pull the meters around here. It would add tons of time to restorations if they had to go house to house especially in the winter when meters are snowed in.
The interlock kits linked above are UL listed. I am sure they will answer any state specific code questions people may have. There may be an issue with NJ code. No matter the method there really isn't much excuse for not doing an interlock.
 
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Backfeeding a generator is like driving a car. You better know what you are doing before driving in heavy traffic on an Interstate hwy. Lots of things are dangerous in this life.
 
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