My suggestions for wiring an emergency generator into your breaker box

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WyomingMan

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I have a home with a 240V well pump and a 240V hot water heater, and a 240V heat pump/AC. I live in the boonies. Without electricity I have no water after the pressure tank is empty (see my other post about that). I found there are 3 basic ways to wire a generator into a house.
1. Buy and install a monster 200A transfer switch that switches from "mains" to generator in front of your breaker box. Disadvantage of this is expense and difficulty in wiring since you may not have access to the heavy mains coming into your breaker box. I rejected this.
2. Install a transfer switch such as this:
https://www.lowes.com/pd/Reliance-306LRK-6-Circuit-Transfer-Switch-Kit-P2/50436688
In some cases this would be effective. You have to decide in advance WHICH six circuits you want to have back up capability. You can switch each of the six individually from mains to gen. You have to locate this close to your breaker box since you have to run the six branch circuits from this new box to your main box. Trouble is that if you have 240V circuits like me, they take up TWO positions. So my pump and HW heater take up 4 of the six. I'd need one for the fridge, that leaves one for the living room. Or maybe bedroom? Or bathroom? They make a similar model for 8 or even 10, but even so, what about the garage, other bathroom, etc? You certainly cannot make ALL of your circuits switchable with such a device.
3. Install a simple mechanical interlock and "backfeed" a 30A 240V circuit to your generator using a outlet box on your outside wall. You only need to add one dual circuit breaker to your panel and run the wires from that breaker to your new gen box. I used this:
http://www.interlockkit.com/
The kit is unique to your brand of breaker box and absolutely prevents connecting your mains and generator together at the same time (poof!). Typically, you add a breaker to the top left or right of your breaker box and run the wires to your gen input line. You can move the breaker that's already in that position down one position by just moving them all down one (double) space on that side.
When you power fails you flip your main (mains) breaker off, slide the lockout tab up, and turn on your new branch breaker. Fire up your gen and you can provide power to ALL your circuits. Simple and safe.
My modest 5500W 240V gen cannot power my 4,500W electric water heater AND my 1HP well pump at the same time (nor the heat pump but I have a propane heater for that situation). As long as I don't try to heat water and pump water at the same time I'm good with everything else in the house being connected. I just have to load manage but since the heater only needs to be run once a day, at most, and the well depending on water usage, this works out well. Every room in the house has lights, the garage door opener works, the propane range and MW work fine, etc.

Anyway, this is what I did and it works great. Did this on two homes. Your mileage may vary . . .
 
WyomingMan, that is exactly the same conclusion that I came up with. I went on step further. I have a son that is a metal fabricator and after showing him the InterLock kit, he built one for me that worked smoother that the one you purchase. Said it was one of the easiest things he has built in a long time.
 
At my parent's place I think we have the big transfer switch you didn't like. I think they had to turn off the power while they installed it, if I remember correctly. We can theoretically run the whole house on it but of course the generator isn't powerful enough for that so we have to be careful.
Before we had that installed, my dad had rigged some method where you plug the older (much smaller) generator into a specific circuit and power it that way. It could only power a few things at a time and we had to be super cautious about turning everything off and only running what we needed. I don't know that I would recommend this method.
 
At my parent's place I think we have the big transfer switch you didn't like. I think they had to turn off the power while they installed it, if I remember correctly. We can theoretically run the whole house on it but of course the generator isn't powerful enough for that so we have to be careful.
Before we had that installed, my dad had rigged some method where you plug the older (much smaller) generator into a specific circuit and power it that way. It could only power a few things at a time and we had to be super cautious about turning everything off and only running what we needed. I don't know that I would recommend this method.
Yeah, "careful" is the operative word in that situation! And plugging a gen into a specific outlet (after turning the Main off) will only power 1/2 the circuits that share that phase of the power bus in the breaker box.
I have a second home that only has 120V devices (gas water heater, furnace, stove) and a smaller 120V only gen. I feed the four conductor cable (hot, hot, neutral, gnd) to an outside box where I connect the two hots together at the hot pin of the 20A outlet with perpendicular pin. This allow my modest gen to power ALL the outlets and lights in the house. Totally non-code, but the metal slide lock out plate prevents any catastrophic melt down. Works great.
 
I bought a hand pump for the well. The brand is Simple Pump and it is spendy, but it will pressurize your home's line so you can actually take a shower. I have a transfer switch going to a few breakers, fridge, fan on wood stove, lights, water heater even, etc. Propane and gas can run out. I just picked up the Titan solar generator. SPENDY, but you can bring it in without fear of fumes, and noise isn't a problem. If the sun goes out, not much prepping is going to save you.
 

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