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Installing a generator back feed system into the circuit panel.

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bender1227

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Discussion starter · #1 ·
I am planning on installing a back feed system into my circuit panel and want to make sure I have all the plans laid out correctly. My generator is rated for 30 amps so I plan on buying the 30amp Reliance Power Inlet Box, 8 gauge wire, 30 amp Siemens breaker, and the proper Interlock switch for my Siemens panel. A question that I have is; I'm going to be running my generator 20 feet away from my house for safety reasons and it's going to be pushing 30 amps out. Will an 8 gauge wire work for this since it is such a far distance that it'll be pushing those amps? Also, what type of conduit should I be using? I plan on using an outdoor rated and non-metallic conduit.

Thanks guys!
 
#4 ·
best to contact an electrical contractor for your install.

the questions you are asking are that of a pure uneducated novice.

when running the generator, when the power is out, should your rube goldberg contraption backfeed a line, the POCO line crew will take you out for a beer....

well beer for them anyways while they kick your azz...:laughing:
 
#5 ·
'Round here, if the line crew hears a genny running during a power outage, they'll investigate and look for an inspected transfer switch. If they can't find one or there's no record of one, they'll drop the line to the house before they proceed with any more repairs.

It's not until the homeowner gets an permit & inspection (both POCO and AHJ) before they get power turned back on.
 
#6 ·
So if I fire up a gennie and run an extension cord through a window to my frig, the POCO will chop my line? I think not.

I have the setup the OP is contemplating. Over multiple outages, the POCO has never asked to enter my house, with the gennie running and them working only 1-2 poles away.

Funny thing, they have ways of telling whether you're backfeeding the grid.
 
#7 ·
Tinstaafl said:
So if I fire up a gennie and run an extension cord through a window to my frig, the POCO will chop my line? I think not.

I have the setup the OP is contemplating. Over multiple outages, the POCO has never asked to enter my house, with the gennie running and them working only 1-2 poles away.

Funny thing, they have ways of telling whether you're backfeeding the grid.
Click to expand...
I think so. Seen it. Been there.

I can't speak to what the POCO in your area does, and you can't speak to what the POCO in my area does.
 
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Discussion starter · #10 ·
This is a very standard installation in my jurisdiction. You just need to use a Interlock switch so you can't back feed the power out to the Utility lines outside. Interesting discussion... not one question answered... I've been working with electric for a long time and pass all my permits. Each jurisdiction will have their own codes that they adopt so it's best to call them up and ask.
 
#12 · (Edited)
If you’ve been working with electricity for awhile why bother asking about if a 30 amp generator needs larger than 8 gauge wire for a 20’ run? Also, if you are burying the wire I’d use pvc. Honestly, if you are using a twist lock plug on your generator and SOOW 4 wire you might have trouble getting the 8 gauge to fit the plug terminals.
 
Discussion starter · #13 ·
Morning Wood said:
If you’ve been working with electricity for awhile why bother asking about if a 30 amp generator needs larger than 8 gauge wire for a 20’ run? Also, if you are burying the wire I’d use pvc. Honestly, if you are using a twist lock plug on your generator and SOOW 4 wire you might have trouble getting the 8 gauge to fit the plug terminals.
Click to expand...
The reason is that I have never done this particular project before and am doing my due dilignence before I start. The amperes/length chart I was looking at said for a 20' long cord that is going to run up to 30 amps it should be 8 gauge. From my understanding most people use 10 gauge for this. Maybe I can run 10 gauge from the inlet box to the panel and buy a heavier gauge cord to hook into the generator that will run to the inlet box. What do you recommend?

Also, I think I'm going to use this casing; https://www.homedepot.com/p/AFC-Cable-Systems-1-2-x-6-ft-Non-Metallic-Liquidtight-Whip-8028/202286682

The wire is going to run straight back through the inlet box, through my exterior garage wall, then into my panel. I'll use the casing in the garage where the wire breaks through the wall and into my box. My question was more towards a recommendations on what type of rating should the casing have? I know the casings are rated for (x) amount of volts etc. and wanted to stay within range. I think that product should cover this application.
 
#14 ·
I am not going to bust your chops on your electrical experience. But I do have a question for you regarding your amperage requirements. How do you expect to power your entire panel on a 30 two pole breaker? I understand that since your generator is manual start you can pick or shed the loads as needed. Seems like a real pain in the arse when there are backup generators with their own panels and interlock that would simplify your installation. Yes, they cost more. But if it is your intention to use a portable generator you would be much better off to get a panel just for that purpose along side your primary panel. They have double throw breakers that eliminate the need for an interlock since their function won't permit any back feeding. Since you are going to be there anyway, this seems like a better functioning device.....approved and safer. Seems like you are re-inventing the wheel.
 
#15 ·
The hassle with those transfer switch setups is that they generally only handle a few circuits. There's a fair chance that during an extended outage, you're going to wish you had power to a circuit that didn't get wired into the switch.

The interlock system is just as safe, and will provide power to every circuit in the house. Its only downside IMO, and it's a small one, is that it won't automatically switch back to grid power when it's restored. Easy enough to set up an alert sensor for that.
 
#16 ·
MoArk Willy said:
I am not going to bust your chops on your electrical experience. But I do have a question for you regarding your amperage requirements. How do you expect to power your entire panel on a 30 two pole breaker? I understand that since your generator is manual start you can pick or shed the loads as needed. Seems like a real pain in the arse when there are backup generators with their own panels and interlock that would simplify your installation. Yes, they cost more. But if it is your intention to use a portable generator you would be much better off to get a panel just for that purpose along side your primary panel. They have double throw breakers that eliminate the need for an interlock since their function won't permit any back feeding. Since you are going to be there anyway, this seems like a better functioning device.....approved and safer. Seems like you are re-inventing the wheel.
Click to expand...
Thats the way mine is run and thousands of others here, I have 40' cord to gen. very easy to do when power fails, main breaker switched to off, slide interlock bar, 30 amp breaker on, we have power
 
#17 ·
Yup, that's the cheapest, easiest way to do it with a main interlockout. Gives you flexibility. What's a small gentran panel start at $400, for six or eight ckts?

For some people that is the best for them. Where they don't need to be technical.

I've had a few people that $5-20 k wasn't the problem. The problem is being out of power. For them auto xfer switch to their whole panel. With a permanent generator.

You can also buy a gen cable with breakout plugs so you run in the house and down the hall without touching any of the building electrical system. That's probably the easiest.

Solutions for all budgets and abilities.
 
Discussion starter · #18 ·
My particular installation is going to cost me less than 200$ and it could be way less than that if the interlock switch wasn't 75$. The locking switch is a very small piece of metal that is drastically overpriced, but it makes it legal. They probably have patents protecting the product. I already have the generator that I was manually running extension cords into my house everytime the power went out which was a nightmare. Now all I have to do is turn on the breakers that I want. My generator generates 5000 watts. I haven't calculated everything I can run on it yet but that'll handle all my imporant systems like heat, refridgerations, and lights for sure.
 
#20 ·
MoArk Willy said:
Well.
If you can make that work for you, great.
Best of luck.
Click to expand...
You can run a lot on 240V 30A. Whole house pretty easy as long as you don't have any resistive heat loads or motor start ups other than fridge/freezer/furnace.

Most houses use 1/4 that on average (which works out to a $150 electric bill), so removing the high load and peaky loads, not too hard.
 
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bender1227
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