GENERATOR Q: Why do I need a bypass panel? Can't I just throw the main breaker to isolate the house? : LUSENET : TimeBomb 2000 (Y2000) : One Thread

Why do I need a bypass panel? Can't I just throw the main breaker to isolate the house?

-- SafePower (,@,.,), May 13, 1999


Yes, but if your forget and throw it back without taking the generator off, you'll back feed the line. Than when a lineman comes out to fix it you'll zap him. If he (or she as the case may be) get's injured or dies look for a nasty law suit and maybe some jail time. You might also damage some of your neighbors equipment. They may not be happy about that. You might even damage some of the utilites equipment. They may all want you to pay for that.

-- The Engineer (The, May 13, 1999.

He is somethings I posted at a differnet forum on this topic.

Are people allegric to transfer switches? Yes backfeeding can be "safe" *IF* you do 100% of everything right.

Ever notice that homo sapiens tend to make mistakes? Ever heard of Y2K? It is a mistake.

Backfeeding can be done correctly and safely. It can also be done with disasterous effects when you are woken up at 4 AM with an emergency and everybody is screaming, your brother in law was "just trying to help", you are the emergency at 4 AM and your wife/son/daughter is trying to duplicate what you told them two weeks ago, etc.

If you want to cheap out, forget the house wiring. Just buy a good extention cord that is the right guage and length for the job and go from the generator to the load. You can do this several ways. Run multiple extension cords from the genset, or run one big freaking 8 guage from the genset to a 4 outlet box in your house and run smaller gauge extentions cords from there.

The concept of either extention cords or a transfer switch is to make it impossible to make an error.

Followed by Al's post of

:pick the best choice: 1. do you think that a phrase like "it looked ok to me" will keep you out of jail for manslaughter after you kill a lineman by backfeeding into the power grid. 2. do you think that your wife will understand when she sorts through the charred remains of her house that you thought "it looked ok to me". 3. do you think your generator warranty will cover the generator fire caused by having both line and generator connected at the same time.


Followed by me again.

You know Al maybe I'm too subtle. Why is it that so many people are trying to push water uphill with a broom? Here's a reply I made to an e-mail a few days ago. His "special circuit breaker" was another back-feed cobbled mess, but it was "ok" because he had a main disconnect and his brother the electrician [insert various derogatory statements here] repeatedly told him just how to do it. I dearly hope that nobody's brother like this is up wind from me on a dry day.

The following is NOT inteded to offend, however......... Ahem... This "special circuit breaker" has me worried. I will ASSUME that the output of the genset goes into your circuit box via this "special circuit breaker" for the whole house. I will assume that it is just a ganged circuit breaker and not a big old DPDT transfer switch. (I hope I'm wrong and it is a DPDT, but I doubt it) QUESTION: how do you disconnect the power company from your circuit box?!!?

Scenario #1: Power fails on 1/1/00 at 00:01, you tough it out till 6:00 AM, fire up the genset, let it warm up, bring it up to speed, go in your basement and trip that "special circuit breaker" and the genset comes to a violent halt or the breaker trips off. Why? If you don't disconnect from the in-line, you are attempting to power all of your neighbor's houses.

Scenario #2a. You don't have any neighbors, you live 5 miles from the nearest windmill or silo. The breaker at the substation that feeds the transformer on that pole by your garage has tripped, disconnecting you from the electric outside world. But you are still connected to that transformer. Lineman Al is trying to get the substation back online. Little does he know that you are trying to (and succeeding) to power the high side of that transformer to the tune of 4,400 volts. No problem on your end since the high side isn't connected to anything, so no power is drawn. Anyway he "knows" that your feed line is dead, after all the substation's breaker is tripped. Al gets careless and touchs your "dead" feed. Your lights dim a bit as 4,400 volts does a MacGiver on Al's heart. Al's widow shows up with a lawyer, rather than a .44 which was her first thought.

Scenario #2b. Al doesn't get careless, the power plant goes back online, he sucessfully closes the circuit breaker at the substation, your genset is out of phase with the power station and tries to run the power station backwards for the 1/1,000th of a second before the "special circuit breaker" can kick out, the power station wins. Your lights blink off and then back on, and you notice this AWFUL smell and smoke coming from your ex-genset.

You absolutely need to have some way to disconnect your circuit box from the grid. A nice Square D or other good brand transfer switch is the right way to do it. You can (illegally) disconnect (pull) your watthour meter (this would be not IBEW - International Brotherhood of Electrical Workers, but OBEW - Ozark Brothers Electrical Worker method).

Ie., these wonderful things happen when somebody back feeds and makes an "oops".

P.S. Al - love your #2, if that doesn't make em' think nothing will (which is a possibility).

Hope that gets the idea across. The whole idea is safety so that it is impossible to make a mistake.

That said, there does apparently exist some sort of linked quadruple breaker that will pull the main offline before connecting the genset. I've seen these mentioned on the net but never seen one in the flesh. Sure hope its linkage never fails! I'll stick to a nice ol' Square D DPDT switch thank you.

-- Ken Seger (, May 13, 1999.

Liabilty...Liability....Liability.... I have spoken with a number of utility company officials around the country, and this is a major concern of theirs. As a matter of fact, I know of at least two which are planning public information campaigns regarding this issue. I am a firm believer in back up power, beyond the Y2K issue. But, back up power is a system, not a generator. If you are going to do it, do it right. Install a transfer switch.

-- codebuster (, May 13, 1999.

Get yourself a nice Trace inverter with a built in transfer switch. (If you can still find one this close to Y2K. Good luck.) Have it installed professionally. Then, STRICTLY by the book, you hook all this stuff into it: 1) utility power 2) generator 3) wind generator and 4) solar-charged battery bank. When the power fails, you're off the grid in 34 milliseconds. A few milliseconds after that, your battery bank begins pumping 120v into the house. If the batteries drop below a certain charge, the inverter tells your electric-start generator to turn on, charge the batteries and send 120v to the house. Admittedly, this route could be expensive, but it sure is smooth and reliable.

-- Prometheus (, May 13, 1999.

Haing fooled around with generators for awhile--the cheapest and safest way to run household appliances is to plug directly into the generator. The option of using an eight gauge cord to a breaker strip works just fine. You don't have to worry about installing a transfer switch. You don't have to worry about frying your house or anybody along the line.

Think about it, what do you want the generator to do? To run your fridge? Uneconomical. Run the furnance Blower? Fine. Wire a system so that the furnace can be disconnected from the house and run via cord to the generator. What else? Microwave. Silly. TV. Run directly to the generator. Satellite? same thing. Computer, same thing. Some lights?, same thing.

I purchased this year, the last of the Mohicans. A honda em350. 300 watts of power. I don't need anymore. Operates some lights, my 12 volt furnace and tv.

Its simple folks. You will kill yourself, or somebody you loe or een somebody you don't know by fooling around with trying to plug your generator to your house. If you must, contact a licensed Electrician to do it for you. Why jerry rig some up when it is not necessary.

Quite frankly I am waiting till next year to purchase my high-output generator. There will be quite a few used ones around.

But my main point is think about what you want your generator to do? For the most part it won't do what you want it to do anyway. Not unless you have one of those 10kw puppies--otherwise a 4kw or 5kw is not real feasible to run the whole house.

Worried about refrigderation? Pick up a used RV fridge. runs on propane. Available from 400-1000 bucks. A wise investment me thinks

-- mrsbigdaddy (, May 13, 1999.

Are you willing to risk a neglegence lawsuit that could whipe out your family financial present & future, and maybe killing someone to save $85 on a transfer switch at Home Depo? Transfer switches are not expensive and not hard to wire in.

-- Buffalo Bob (, May 14, 1999.

You might also call your local power company. They have some rules concerning this. Yes. They do.

If, for example, the meter reader comes by and notices anything odd with your meter, or strange wires coming from the house to a 'box/shed' in the yard, he/she will report it. If the power company wants to, they can cut your power until the investigation is complete concerning the oddities reported. How long will it take? HA! Try and get an answer to that! they can take their time on it! They are the power company!

Most electric companies require that they be allowed to inspect this sort of thing.

Jail is not where you want to be, even if it is better than being dead! Or is it better?

-- J (, May 14, 1999.

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