[zeke]

I have also considered a portable  gen for many years. Seems to me the only emergency power needed is for the furnace in the winter, and the fridge in the summer. And maybe a couple lights.

"experts" say do not backfeed the breaker box (from the garage for ex). I have 12 gauge wire to the garage and would be backfeeding about 30 ft. I would only power the fridge or furnace. I don't think i would need 220v for emergency power .

Why is a knife switch needed to block the source in(com ed) ? ---- can't you just throw the main breaker switch at the breaker box ? Or pull the main meter ?

Yes, you can just run electric power supply cords for the fridge, lights etc, but there is no plug for the furnace.

any comments or help ?

thanx
zeke

[srb]

I have also considered a portable  gen for many years. Seems to me the only emergency power needed is for the furnace in the winter, and the fridge in the summer. And maybe a couple lights.

Hello?  And the stereo!
 
Steve

[zeke]

hello Steve --------  yes, as soon as the beer is cold and the house is warm i will turn on the stereo !

 

zeke

[Wayner]

I have also considered a portable  gen for many years. Seems to me the only emergency power needed is for the furnace in the winter, and the fridge in the summer. And maybe a couple lights.

"experts" say do not backfeed the breaker box (from the garage for ex). I have 12 gauge wire to the garage and would be backfeeding about 30 ft. I would only power the fridge or furnace. I don't think i would need 220v for emergency power .

Why is a knife switch needed to block the source in(com ed) ? ---- can't you just throw the main breaker switch at the breaker box ? Or pull the main meter ?

Yes, you can just run electric power supply cords for the fridge, lights etc, but there is no plug for the furnace.

any comments or help ?

thanx
zeke

The 2 power sources must never mix. AC means alternating current which means that if the 2 sources were to ever mix, their frequency must exactly align.

In another words, the line frequencies of both electrical sources must be synchronized.

Wayner

[chester_audio]

Here in New Hampshire it is not unheard of to be without power for several days, or weeks, at a time. We are self-contained, well, septic, satellite tv so a generator makes good sense. As long as we can get the gas to run it, and heating oil, we hardly notice power losses.

We had a transfer switch wired into our main panel and an outside plug-in when we built this house. I went with a Generac this year when the old Home Depot special gave out after 12 years. (Not bad for $400.) The new generator is 8kWatts with a 10K peak, and electric start. The well barely loads it when it starts. I think we have about $3K (10 years ago) in the system. Considering the price of motel rooms when you're competing with every one else, it pays for itself quickly in our situation. Not to mention the extra rest we get by not having to deal with all of that upheaval.

We had an ice storm a few years back that shut everything down for a week to 10 days. Out of 15 homes in our neck of the woods, only one other neighbor had a generator. As luck would have it, he lived exactly on the opposite side of the neighborhood. So folks were going to his house or ours depending on which was closer. It was fun for us, kind of like winter camp, with lines to the showers and kitchen. Our neighbors were starting to cook food before it went bad. Ended up being one heck of a party one night when Charlie, with the other generator, ran out of gas. So everyone ended up at our house. One year later and almost every house had their own generator.

I was listening to my system a couple of nights on the generator during that ice storm. I have never heard the background that quiet!

edit: Warning. If you run your electronics off of a generator be sure to use a UPS or something to protect your gear.

[zeke]

hi Wayner --- thanx for your comments

I understand the two sources must never mix, and that it can be dangerous to electric company workers if the port gen backfeeds into the electric company lines. But my question still, is why is a special throw switch needed if you can simply trip the main breaker in the breaker box, or for that matter pull the electric meter outside, before you start backfeeding your breaker box from the port gen.

zeke

[TheChairGuy]

Don´t know what you mean by solar generator? do you mean solar panels? I been living off the grid for 20 yrs and designing and installing systems for 18 yrs and I would strongly disagree with wgscott on Real Goods they would be the last company I would deal with ,highly over price and the owner is just a hustler trying to make a buck IMHO.

Mike

I was thinking of something like this: http://www.acehardware.com/product/index.jsp?productId=4310054&CAWELAID=546187143

Panel(s), controller, battery, inverter, etc all-in-one.

I'm leasing a home right now (quite by choice), but I'd like to have back-up for grid fry, tremors, SHTF scenario's, etc.

(apologies to OP/jermmd for taking his original question slightly askew now into solar) 

John

[jermmd]

Costco sells a bunch of Solar generators for the home. I don't think they're good for emergencies but they mat pay for themselves over time and they can help in an emergency.

Joe

[Wayner]

hi Wayner --- thanx for your comments

I understand the two sources must never mix, and that it can be dangerous to electric company workers if the port gen backfeeds into the electric company lines. But my question still, is why is a special throw switch needed if you can simply trip the main breaker in the breaker box, or for that matter pull the electric meter outside, before you start backfeeding your breaker box from the port gen.

zeke

One system must be disconnected, while the other is connected. The knife switch (not recommended) will accomplish this, but contactors are much better (you won't loose an arm).

Wayner 

[wgscott]

Perfect day here.  Sunny, upper 70s, etc.  Not a cloud in the sky.  Power failed at 8:30 am and still out.  I've fired up the generator twice now to take showers, etc.  This is well worth having, but it would be kind of nice to have a first-world electricty grid.

[wgscott]

One system must be disconnected, while the other is connected. The knife switch (not recommended) will accomplish this, but contactors are much better (you won't loose an arm).

Wayner 

What's wrong with a knife switch?  Should I get it replaced?

[djbnh]

Here in New Hampshire it is not unheard of to be without power for several days, or weeks, at a time. We are self-contained, well, septic, satellite tv so a generator makes good sense. As long as we can get the gas to run it, and heating oil, we hardly notice power losses.

We had a transfer switch wired into our main panel and an outside plug-in when we built this house. I went with a Generac this year when the old Home Depot special gave out after 12 years. (Not bad for $400.) The new generator is 8kWatts with a 10K peak, and electric start. The well barely loads it when it starts. I think we have about $3K (10 years ago) in the system. Considering the price of motel rooms when you're competing with every one else, it pays for itself quickly in our situation. Not to mention the extra rest we get by not having to deal with all of that upheaval.

We had an ice storm a few years back that shut everything down for a week to 10 days. Out of 15 homes in our neck of the woods, only one other neighbor had a generator. As luck would have it, he lived exactly on the opposite side of the neighborhood. So folks were going to his house or ours depending on which was closer. It was fun for us, kind of like winter camp, with lines to the showers and kitchen. Our neighbors were starting to cook food before it went bad. Ended up being one heck of a party one night when Charlie, with the other generator, ran out of gas. So everyone ended up at our house. One year later and almost every house had their own generator.

I was listening to my system a couple of nights on the generator during that ice storm. I have never heard the background that quiet!

edit: Warning. If you run your electronics off of a generator be sure to use a UPS or something to protect your gear.

I'm in NH, we purchased a generator after that same storm - we were out of power 8-9 days. Huge pine came down and knocked out my chimney flues, got a new stone chimney via insurance, and took the leap re: Generac 8KW + electric start, transfer switch wired into our main panel and an outside plug-in. We're on well, septic, etc. The piece of mind with having the back up is absolutely wonderful, should have done it years ago.

[Wayner]

No, a knife switch is fine (is this like 1950?), just use the hand you don't write with to make the switch, just in case it gets blown off with an arc-flash explosion.

Perhaps some of you DIYers need to go to a couple of NFPA-79e classes, to learn what even small currents of electricity can do to your body.

A simple 15 amp, 120 volt outlet can deliver 50,000 amps for a few micro-seconds. Enough to blow your ass up, and burn you to hell. In my other job, I was an electrical designer for a fortune 500 company, designing AMMs that are 208 or 480 volt 3-phase stuff. That is nasty stuff, but the lowly 120/240 circuits supplied to our homes is quite deadly. If you don't know what you  are doing, get someone who does.

Yesterday, I was touring a storm damaged area and came apon a fellow that was removing tree limbs from a 3-phase high voltage line. I got out and asked him what he was doing. He said it was his tree that fell on the wire and he wasn't going to let the utilities people get his firewood. I said, I hope you get to use it. A while later, I saw him drive past into town. Perhaps I scared the shit out of him, and perhaps saved his life.

Moral of story, 8 milliamps of 120 volt electricity can kill you very, very dead. Imagine what 50,000 amps can do? Do we have any more DIY portable power generator genius folks here that would like to chime in?

Wayner 

[wgscott]

What we have is called a Double throw safety switch which, perhaps, I am wrong to call a knife switch, but that is what it looks like to me.  The one pictured in the link is very similar, but ours has a longer handle.

I'm not sure how to decode the rhetoric, so just a straight up "it is ok" or "it is a hazard, get someone competent to replace it" would be really helpful.

This, along with the wired-in generator, came with our house.  The house has been inspected both during the sale and subsequently by the electrical utility when we had solar panels installed.  Neither objected to this switch.

[ctviggen]

Costco sells a bunch of Solar generators for the home. I don't think they're good for emergencies but they mat pay for themselves over time and they can help in an emergency.

Joe

Who knew Costco sold this stuff?  That's not a bad price -- $3.50 per watt.  I had read it was about $9/watt including installation. 

[Tubeburner]

The generator for home use can be very simple. First , you need to know what you plan to run in your home AND how much amperage these items draw for start up and run mode. The start up of a AC unit might be 40-50 amps on 220/240. A well unit may be either 110 or 220, so if these are necessary items that you want to power, you need the amperage to start the units.

My electrician installed a cable and plug on the back of m house to my main breaker panel. I shut off the main and all breakers for circuits in my house. I plug in the generator and kick on the breaker to back feed my panel. I then turn on the breakers one at a time that I want to use, like the kitchen, water pump or heat. I keep the amperage draw as low as possible since my concern is water, keeping food cold and in winter, not freezing the pipes or myself.  I have found a 10,000 watt generator will take care of most homes for emergency use. If you want to run everything, then you will need more.

Disclaimer: This is for information only. Please check with a qualified electrician before attempting to hook up a generator to your home!

[Wayner]

What we have is called a Double throw safety switch which, perhaps, I am wrong to call a knife switch, but that is what it looks like to me.  The one pictured in the link is very similar, but ours has a longer handle.

I'm not sure how to decode the rhetoric, so just a straight up "it is ok" or "it is a hazard, get someone competent to replace it" would be really helpful.

This, along with the wired-in generator, came with our house.  The house has been inspected both during the sale and subsequently by the electrical utility when we had solar panels installed.  Neither objected to this switch.

Calling that a knife switch is a stretch. It's a disconnect with internal guarded poles, fully enclosed and probably lockable. It's manual, but does the trick to disconnect under load.

Wayner

[wgscott]

Thanks.  I am going to get it and everything else in our house inspected by a competent electrician.  There are several other issues that concern me as well.

[ctviggen]

The generator for home use can be very simple. First , you need to know what you plan to run in your home AND how much amperage these items draw for start up and run mode. The start up of a AC unit might be 40-50 amps on 220/240. A well unit may be either 110 or 220, so if these are necessary items that you want to power, you need the amperage to start the units.

My electrician installed a cable and plug on the back of m house to my main breaker panel. I shut off the main and all breakers for circuits in my house. I plug in the generator and kick on the breaker to back feed my panel. I then turn on the breakers one at a time that I want to use, like the kitchen, water pump or heat. I keep the amperage draw as low as possible since my concern is water, keeping food cold and in winter, not freezing the pipes or myself.  I have found a 10,000 watt generator will take care of most homes for emergency use. If you want to run everything, then you will need more.

Disclaimer: This is for information only. Please check with a qualified electrician before attempting to hook up a generator to your home!

I'm going to connect a generator to my home myself (pulled the permit and will have it inspected).  I'm going for a max of 7,500 watts though, and will use a connection on the outside of the house (to which the generator is connected).  I'll pass this into the breaker box and a single breaker rated for the correct amount of current (30 amps).  I'll then drill into the cover for my breaker box so that either the house is powered from the "street", or the generator is powered, but not both.  In my situation, I'd have to get an outdoor transfer switch, which is technically possible but quite hard to do in practice.

[MichiganMike]

After losing power for 4 days one winter, we installed a 12 KW natural gas generator with a transfer switch.  We have critical circuits powered by the generator, including the sump pump, two natural gas furnaces, one AC unit, a freezer, our refrigerator, our internet router, a TV and the garage door opener, as well as lights and outlets in a few critical areas.  The cost was about $6,000 fully installed.

If the power goes out for more than thirty seconds the generator goes on automatically.  When power returns, the generator turns itself off and restores power from the grid.  I have no concerns about running out of fuel for the generator.  My wife knows the standby power will go on even when I am away from home.  The generator runs a self-test once a week, so I am confident it will run when needed.  It operates quieter than a portable unit and produces power stable enough in voltage and cycles to reliably power electronics and the microprocessors which are in so many appliances today. 

Yes, a standby generator is more expensive than a portable generator, but the peace of mind is worth something.  Some obvious advantages over portable units include, you do not need to manually start the generator, plug critical circuits into the unit, provide gasoline every few hours or worry about carbon monoxide from the exhaust.