Safest way to switch 240VAC

I have a generator I bought for my home. I want to be able to hook it up to the breaker box so that when the power goes out I just head out and turn on the generator.

My first thought was to use a relay to connect the generator to the breaker box when the power went out. But, this got me to thinking about safety. I want to make sure that my generator doesn't stay on and connected when the power comes back. Plus I would like some redundancy.

If I did this, I would move the circuits I wanted out of the primary breaker box and put them in another separate box and just control the power to that whole box. This is why a relay would be nice because I isolate the two power sources. Would an RC circuit or some other form of delay circuit be prudent since sometimes the power flickers and I don't want it to switch back til the power is stable. To be honest, 5 minutes sounds like a good delay, but that is not possible with an RC circuit. So I would have to step up to a 4060 or something similar.

Anyone know of a better way?

 

I actually know of a working system like this near to where I live. It is used in a pump house to provide water to some 400 people when the power drops. The generator starts automatically and from what I seen there is a simple relay/switching device that sits between the generator and breaker box. The question is, when does the switching take place? When the power drops out from the elec. co or when the power comes on and off from the generator? I might have to go take a closer look at that other system to see exactly how it is wired up.

 

This is what I had first thought of as a possible solution. The break then make operation of the relay would make sure the two power lines where isolated at all times and that is what I want. safety!!

 

Well I wish it was that easy to get an answer, but I called the electric company and asked them flat out, does work on my side of the meter require inspection? They told me "We don't know, you will need to call an inspector." So I call the inspector and he says "Is it a new installation?", "No", "Then it won't need to be inspected."
As for the insurance company. They just needed some information from me. One of those questions was how up to date was the electric. I told them that I had been working on it myself. As when I moved in I rewired all the rooms that had old style tub and knob wiring. They told me that was great and approved my application for insurance. No inspection or any visit from them, just my word on the matter.

So with that said I am more then happy to do the work myself. If no one cares about whether it needs inspecting and my insurance co. could careless that I do the work. Then I am not gonna worry about it either. I am going out of my way by asking this question here, because I care more then "they" do.

I have done plenty of residential wiring that has been inspected and approved before, so I feel very comfortable doing the work.

 

I got to thinking about what everyone here has said about the guy outside working on the power line. But, what is the difference between me and my generator and a a solar/wind generator back feeding power to the grid?

These energy systems don't stop working just because the grid goes out, so how does the lineman protect themselves from these sorts of situations? Seems to me their procedures must account for this and if so, then that should account for my system as well.

I am now convinced more then ever that I should probably buy a UL listed transfer switch that is certified to do the work I am asking, but I will be installing it myself!

 

That wouldn't make a whole lot of sense unless you are talking that they disconnect themselves from the grid when the grid power goes out. If that is what you meant, then I guess I understand since most commercial inverters as I understand it produce power in sync with the grid to sell it back to the company.

 

yeah that is the idea, I am not looking to power the neighborhood. scratch that, diode won't work with AC.

I am not looking to power my whole house, just some necessities I can't do without. Power for heat, refrigerator, and my network/femtocell so I can have emergency access