Warning : Steps to safely connect generator to your home wiring

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To anyone with generators

I am glad you are preparing for Y2K but using the proper sequence of steps to hook your electrical generator to your homes circuits is crucial. Otherwise you might kill a utility worker and you might damage/ruin the things you intend to power with your generator.

Simply throwing your home electrical distribution panel's MAIN switch is NOT adequate to disconnect your home from the utility grid. You still could kill a utility worker because some of the circuits on your distribution panel may NOTgo through your panels MAIN disconnect switch. Often the circuit breakers for your furnace circuit, kitchen range circuit and air conditioner circuit connect to the "feed buses" in your panel. My homes Square D Company panel is this way. (Look at the diagram for the bus connections on your distribution panel's door because what I call here feed bus and circuit bus might be reversed in your panel configuration.). The utility power feed is clamped directly onto the "upper bus" The MAIN switch connects / disconnects these "feed buses" to the panel's "circuit" buses which supply the circuit breakers for the other house circuits. The MAIN switch does not connect/disconnect the feed bus circuits - only the circuit bus circuits.

But the former owner of my house had also improperly (and naively) connected some house circuits to circuit breakers on the "feed bus". If I had plugged my generator output cable into a wall outlet on one of those improperly connected feed bus circuits I would be feeding 110 volts through the circuit breaker, the feed bus, then out through my home's big electrical feed cables to my neighbors and through step up transformers to utility workers. I might easily find my self guilty of man slaughter.

What is the solution? Simple. First take the cover off of your electric meter box and pull out the meter mechanism. Of course it is against utility company regulations but if Y2K hits, the localutility guys will thank you for not frying them. Secondly throw OFF each and everyone of your individual circuit breakers. Next go around your home and unplug everything - even those items you intend to power with your generator.

Do the following steps if you intend to power one of your circuits by plugging an extension cord from your generator into a wall outlet on that circuit. Plug your male-to-male extension cable (it is called a 'dongle' by computer networking geeks) into an outlet for your home. A male-to-male extension cord is dangerous to handle if either male end might be 'hot' with voltage. But throwing the circuit breakers and removing the utility meter will guarantee the circuit is not hot.

Your generator is not yet connected to anything. Note that it takes a few minutes for a generator to warm up and produce "clean" 110 volt power. Unclean power damages motors in your appliances and ruins electronics. So now start up your generator and give it a chance to warm up and stabilize its output voltage.

Now plug your extension cord into your generators output receptacles and throw the switch on the generator. Now go inside your home and plug in or turn on, one at a time, the things in your home you need to power with your generator. If your generator starts to falter or the lights flicker you know your generator is overloaded.

When your generator needs more gasoline you must shut down your generator or risk a deadly explosion. Do not pour gasoline into your generator's tank while your generator is running. Gasoline fumes are much more ignitable than the gasoline liquid. Explosions and burns are extremely nasty and you might not get any help from a fire department or hospital. Refuel the generator and wait a few minutes until the gas fumes have dispersed.

Shortly before refueling your generator, you should disconnect or power down all items in your home that you have been running off your generator. Why ? An electrical generator produces very "unclean" power when it starts up, shuts down or when there is a big change in the load of things it is powering.

Final point. Generators produce poisonous fumes. You might consider running a small house fan off your generator power outlet to continuously blow the generator exhaust fumes away from your home.

You are no good to your family if you are dead or disabled.

Regards, Ron

-- Ron (judy_sander@hotmail.com), September 18, 1999


Sorry, I just caught a typo in my 3rd paragraph.

The third sentence from the end should read The utility power feed is clamped directly onto the "feed bus".


-- Ron (judy_sander@hotmail.com), September 18, 1999.

Check out:

My hydro panel completely disconnects from the utility when the main switch is off. It's a 8 yr old home.

-- Cable_man (tlangan@iname.com), September 18, 1999.

Ron, and all others who read this: As a licensed contractor for Air Conditioning equipment in Arizona I feel qualified to comment. Although the effort is admirable, unfortunately there are errors in Ron's instructions. In other words, Ron is WRONG about this. I strongly suggest Ron and all others who don't actually know, have someone qualified come put a transfer switch in for you. DO NOT ATTEMPT THIS YOURSELF. Ron's post is obviously well intentioned, but incorrect. Get qualified help, or buy lots of flashlights and batteries. You will be better off in the long run. PS: If you insist on saving a buck and trying to do this yourself, at least consult the generator manufacturer's instructions FIRST!

-- Tim Castleman (aztc@earthlink.net), September 18, 1999.

If you have a generator and have NOT notified the power company that you have one, the power company will fry your generator. It can back feed into the power lines and kill a utility worker, so you better know what you are doing.

-- eddy current (eddy current@eddycurrenttt.com), September 18, 1999.


I'm afraid Tim is correct. You are putting out entirely incorrect information. Now, the way you explain your own house system may very well be the way *it* is wired, incorrectly, by the previous owner. The main panel breaker shuts off ALL other circuits. If you turn that main breaker to Off, it will kill everything in the panel on the downside of the main breaker. The lines from outside that feed into the main breaker will still be HOT though, unless you remove the electric meter, which will then stop all current flow to the panel. I know you were just trying to help, but you have put out bad information.

-- Gordon (gpconnolly@aol.com), September 18, 1999.


Get a very good licensed electrician to do the work.

Have him explain how he is complying with the National Electrical Code or better. Have him show you all of his work, every detail. Have him draw it out as a schematic diagram for future reference. Tell him you want it Idiot Proofed or Murphy Proofed. Use proper enclosures, etc.

Don't take any chances.

-- no talking please (breadlines@soupkitchen.gov), September 18, 1999.

If your Main Breaker does _not_ disconnect your house from commercial power, the wiring is in violation of National Electric Code, and may not even be covered by insurance. You need either a Professionaln Engineer or _licensed_ electrician to check out your system. Something is terribly wrong, and very dangerous.

-- A. Hambley (a.hambley@usa.net), September 18, 1999.

Everybody's a critic/expert.Ron did mention pulling the meter to kill the power to the breaker box.There is a situation where pulling the meter WILL NOT kill the power.This is if the metering setup uses current transformers(CT's) to sense amperage in the service wires,which in turn runs the meter.The service current itself DOES NOT run thru the meter.CT metering is usually seen in industrial type applications,200+ amp capacity services,but some rural electric companies use them on residential setups.

-- Sam (Gunmkr52@aol.com), September 18, 1999.

Call me stupid, but don't you have to have fuel for a generator? And what about the noise? I remember when Hurricane Opal roared through four years ago. We were without electric and phone for 48 hours. After dark the first nightfall, we lit candles - seemed so exciting and somehow a bit romantic. We went out on the porch to revel in the silence. What we heard was our neighbor's generator droning on and on. I remarked, "if it is that loud a block down how awful must it be next to it?" Remembering this and considering the fuel issue - we decided to prepare for primitive living. :-)

-- April (Alwzapril@home.com), September 18, 1999.


You may just be very right about this matter, and primative living. I remember a visit to my great-grandparent's home, when I was very little. They had a farm without electric, running water, or heat beyond the kitchen wood stove/oven. They were very happy and well adjusted. Imagine that!

-- Gordon (gpconnolly@aol.com), September 18, 1999.

i have read this type of dangerous material on numerous websites. DO NOT plug a generator into one of your house circuits and try to feed your breaker panel in this way.

this is a trick used by contractors when they are building a house. the diference between their use and yours is that you are going to try to pump 40-50 amps through your 12-3 house wiring to the breaker panel, this wire in your wall WILL NOT carry that kind of current safely!!!!!!! you will start an electrical fire in the wall of your house when the wire overheats.

the reason the contractors get away with it is because their power use is minimal, a power saw, a couple of lights, thats all. not a refrigerator, lights , furnace, etc. get the point.

if you burn your house down in this fashion the ins co may not pay off as this may be considered a y2k related incident, you may kill your wife and children as the wall will smolder for a while until it finds an oxygen source, and then burst into flames. you may accidentally backfeed into the grid killing a lineman at which time you could be found guilty of manslaughter and do some prison time. you may feed into your neighbors generator causing one or both generators to catch fire. the power may come on and then if your generator is not in sync with the power co it will be damaged by the cross voltage.

i really dont want to here from any moron that thinks he could never make a mistake and not flip off the main circuit breaker. if he has never made a mistake in his entire life then i guess he is due for one.

this will be a major inconvenience, dont make it a tragedy by doing stupid electrical wiring tricks. have the generator transfer switch installed correctly so that you and your family are protected. if you dont know how get an electrician to do it right.

you are storing food, fuel, buying a generator to keep your family safe, now you are going to risk serious harm to you and them by not installing it correctly, where is the logic in that.

now this is only my opinion i could be wrong... NOT


-- juice (electroman@power.com), September 18, 1999.

To learn more about the "care and feeding" of generators check out the juice page at:

John F.

-- John F. (millenniumadrenaline@hotmail.com), September 19, 1999.

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