Generator backfeed revisited

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As the OP, I'll add an anecdote on this very tangent. I was rewiring an attic light, and being uncertain which breaker was which, I turned the light on & flipped breakers until it went off. In an unusual fit of caution, after opening up the junction box, I tested all of the wires inside. To my surprise, there was still a live circuit in the box. The previous homeowner had run two breaker circuits through the same JB. Coulda been unpleasant. Ya just never know unless you check.
Joe F.
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This is permitted by the NEC I think and it is one area that I take strong exception to. In residential wiring I'd like to know that only one circuit feeds a given device.
RB
rb608 wrote:

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It is absolutely possible and can work perfectly. I have a 220V (#10 wire) outlet in my garage, whose original purpose was to power woodworking equipment while I was building the house. When I have a power outage, I throw the main breaker in the basement, plug the generator into this outlet using a special extension cord I made (male on both ends), and away we go--the entire house is powered, though it is probably not a good idea to use the electric range, and my welder is not usable either. Just be sure you
1. Throw the breaker 2. Plug the extension cord into the house outlet 3. Plug the other end into the generator
in that order. Reverse the order when shutting down. This has seen me through 5 or 6 power outages (we don't get very many). The generator is a 5000W generac, not very expensive.

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donald girod wrote:

A possible problem with this, and why I didn't mention a "welder outlet in the garage" in my previous message is the NEC allows you to use #10 wire with a 50A breaker for a welder. You could burn up the wires without tripping the breaker if you backfed this circuit with a generator bigger than about 7kW. (Also if you replace the welder with one that has a high duty cycle and operate it at high power.)
You really ought to pull the meter (tell the power company you are doing this) or padlock the main disconnect, just to make sure someone doesn't come along behind you and turn the mains back on.
Best regards, Bob
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I've always backfed my generator so I can tell you that it works just fine electrically BUT:
1. You can get electrocuted if you plug an operating generator into an existing outlet since the plug will likely be male and easy to touch. I plug the house into the generator via the female end of the cable. 2. You really need to do more than just pop the main. I have whole house disconnects and actually put a padlock on the panel just to be sure no-one else can touch it. 3. You need to sequence circuits manually or your generator could go "poof". When my deep well pump is starting and running I need to insure there's little additional load on the generator. Induction motors consume 3-10X more current starting than running. You need to factor this in to your procedure and you better not be wrong. 4. The receptable you use to backfeed the generator should be a high amperage 220 v outlet such dryer outlet or you might not feed your home properly. Once again you still need to ensure your balancing the homes load with the generator outlet. 5. Your backfeed cable system better be capable of handling the full amperage of the generator.
OK, I think I gave you the straight info. your asking for but the most important advice is that things are at their absolute worst during an outage. It can be dark, cold, and you might be in a hurry to get things online. Mistakes are totally unforgiving.
I have a detailed checklist and I follow it and double check it just like an airplane pilot would. I also have practice outages a few times a year.

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Dave covered things but one overlooked area by most is load. As dave said starting current is much higher for motors. And a good cheap 6 circut transfer panel for 200$ helps you manage that by giving you 2 watt meter to balance your unit. If you havnt actualy gone around with an amp meter and measured starting and run load on every apliance to be used you could not only burn your generator out but your apliances to by overloading. No a generator fuse wont protect you. I dont know what unit you purchased, but I will bet it wasnt a honda or other top line voltage regulated model In which case you would be wise to monitor voltage through your use of switching apliances. Some cheap units can swing 40 v from no load to full load, with corresponding HZ You may be saying BY BY to that new furnaces control board or TV , microwave etc
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Amazes me *WHY* the utilities haven't come out with an "Additional temporary input / utility bypass" meter pan?
-Power fails -Bring portable generator to meter location. -Open side access door of meter pan (Which physically disconnects meter from utility source) -Inside side access is a recessed 20 or 30 or 40 (to match generator's rating) ampere male plug. -Attach female end of extention cord to meter bypass outlet -Attach male end of cord to generator.
Optional:
A solenoid operated ejector which, upon restoration of utility's power, would "punch" the cord out of the side input socket and the door would spring shut. Another option: a fireman switch on the door cover which would shut down the genset if the door isn't open.
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Good idea Buddy they sell everything else, must be a saftey issue.
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There is a connection hub that mounts on the meter base. You plug your generator into it and manage your load off of your regular breaker panel. You can buy one from Dominion Virginia Power for $995. Follow the below link to Dominion Virginia Power's page.
http://www.dom.com/products/generators/hub.jsp
Research on the web shows that some power companies will lease the device to their customers for less than $10/month; Dominion won't.
A thousand dollars is a bit steep for me to pay to be able to connect a generator to my house for the occasional power outage.
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HA HA Budys Here wrote:

They have. It is called a generlink. http://www.generlink.com/about_generlink.cfm One catch they provide it as a monthly billed service. A mere twenty dollars a month. That is not a typo they get 240 dollars a year for it and that to me makes paying for transfer equipment quite reasonable by comparison. -- Tom H
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[snipped]
I posted about the generlink several weeks ago. Dominion Virginia Power wants $995.00 for it installed. They will not lease it. You buy it and can take it with you if/when you relocate. It is nice in that you manage your generator load from your existing circuit breaker panel. However, it is a bit too costly for me.
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Newby wrote:

How much would a 200A DPDT switch in a NEMA 12 (weatherproof) enclosure cost? Put it between the meter and service panel and use it as a manual transfer switch. Not everything has to be automated...
Best regards, Bob
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$299 from Harbor Freight Tools (assuming NEMA 3R enclosure is OK).
-- Mark Kent, WA
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zxcvbob wrote:

-- Tom H
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you can't get electrocuted that way. A severe electrical burn sure, but not electrocuted. Think about it; what circuit are you completing if you touch one prong? (okay, if you touched one prong with each hand, you could get electrocuted, but that is reaching.)
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rb608 wrote:

You know, its because of people doing things like this that we end up with laws prohibiting it, which in turn makes it more expensive for insurance, installation and equipment to protect against doing it. Why not do it right and get a transfer switch? Is it really worth saving a couple of bucks when you run so many risks? The "I'll never do it" and " no one but me will touch it" excuses have killed and injured many. Really, please dont cobble together some lame system that puts others and yourself at risk. Eric
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During the great 1998 ice storm, a friend and I spent some time "inspecting" homeowner generator installations (as a favour to a neighboring township, who by and large were without power for almost a month). We saw a couple of backfeeds, but none of the suicide-cord variety. And we did one ourselves (of a 100Kw generator into the publics works garage).
Or in an earlier situation, someone doing a complete rewire (new panel in a different location) was caught in the middle of a strike and couldn't get the feed moved. So the electrician backfed the new panel via a dryer circuit. In fact, _suggested_ by an inspector.
During an emergency, you do what you gotta do.
That being said, while a suicide cord is "simple", it's quite unsafe in a number of ways, and frankly, while you'd probably get away with it, it's _unnecessarily_ unsafe.
_Unless_ you install a transfer switch, I recommend you use extension cords. If, after the power is out for a day or more, and there's no expectation of power restoration _soon_, and you must must must have backfeed, then consider backfeeding. Instead of a suicide cord, do this:
1) Do what you have to do to disconnect the main feed. Hopefully in a way that's easy to restore when the power comes back. Just switching the main breakers off isn't good enough (even with lockouts). Pull the breakers, or pull off the output of the main breakers. Or something. Pull the meter if you have to (and cover the hole).
2) Direct wire the generator into the main panel or outlet (presumably a dryer outlet or something else large ampacity).
When power comes back, take your time and make absolutely certain you have the sequence right. Turn off the generator _first_.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.
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To begin with, this is dangerous. However, it can be done practically.
I have mine setup in a super-cheap manner. Outside, in a cement block house with a poured slab roof, a 12kW electric start Generac, wired to a dual 30-amp breaker via #8AWG cable. I have that breaker clearly marked with a label that says "Turn off main breaker before turning on this breaker" as a reminder of the sequence and to minimize human error. I am the only person in the household authorized to make the transfer. When the Aug 14th blackout hit, I started the Generac, turned off the 200A main breaker and turned on the dual 30A breaker, feeding Generac's output to both sides of the bus. Voila, normal household operation (excepting my 10kW sound system, which has a peak draw of over 15kW at full power output), but everything else, well pump, stove, air conditioners, works fine. And never in 18 years have I failed to execute the transfer procedure properly. Granted, if I had a lot of money to spend on it, I'd get a 200A transfer switch and a CAT diesel generator and automate the whole process, but this jury rig works and outages are not that frequent. The only way to do this is at the breaker panel. I would not feed back into an outlet. I don't recommend doing this, unless you can garantee that you won't be backfeeding into the electric grid.
-- Take care,
Mark & Mary Ann Weiss
VIDEO PRODUCTION . FILM SCANNING . AUDIO RESTORATION Hear my Kurzweil Creations at: http://www.dv-clips.com/theater.htm Business sites at: www.dv-clips.com www.mwcomms.com www.adventuresinanimemusic.com -

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Why do you only have a 30A breaker on a 12KW generator?
-- Mark Kent, WA
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He is using a dual 30 , 30 for each 120 leg or 60 total.
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