Newbie help! Interlock vs. transfer switch

I've been getting a lot of contradictory information from my local electrical contractors on my way to get an estimate for installing a manual transfer switch between my generator and my breaker panel. I need to clear the picture and hope someone can help me:
I have an off-the-rack Lowe's bought "Troy-Built" 5500W portable gasoline generator and want to install a transfer switch so I can by-pass the house's main breaker and run the generator to supply temporary juice when undergoing extended loss or power.
So far I have gotten the following advice (and prices):
1. Install a 6-circuit manual transfer switch for $600 2. Install the same as above for $1,200 to $1,800, depending on what's involved 3. Told my generator cannot work with a transfer switch 4. Told I'd be better off using a Square D Interlock kit instead of the 6-circuit transfer switch so I can use the entire existing house breaker panel and manage the load myself, not being restricted to 6 circuits (My breaker panel is a GE and supports Square D) 5. Told *never* to use GE Interlock (or any other brand) and stick with manual transfer switches instead, whether 6- or more circuits
All the above info provided by 5 different state-certified, licensed contractors that operate in my local area.
So, I have learned nothing except I need independent advice.
Help?
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Not sure if this is right for you, but my electrician supplied me with an outlet / two plug extension cord. The outlet is outside behind the garage (to keep the noise down when generating). I was told to,when the power is out, throw the main breaker to the off position. Then I plug in the generator to the outlet fire it up and I will have power to my house. You must be careful here not to use everything as if you have normal electricity. Only use what you need. My power went off once since this hook up was in place and I was able to see, have my fridge running and able to watch satelite. My phone and security system was also powered. My genny is 7350 watt, so buy a genny that will work for your application.
This is not for everyone, YOU MUST TURN OFF YOUR MAIN BREAKER, YOU CAN KILL A LINEMAN WORKING ON THE PROBLEM.
Do not attempt this without first consulting a qualified electrician. sorry legal had to be done.
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Shopdog wrote:

A qualified, licensed electrician will not install that, and it will not pass code inspection in North America. No code anywhere allows it anymore because it's part of the NEC now and all local codes are built around the NEC. Also consider your insurance company's response if this setup is the source of any problems, plus the lawsuits possible.
You need a transfer switch.
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Whats to install POP? its an outlet, the extension cord is an extension cord. What code do I have to pass? Its just a supplied outlet leading from the back of my garage. When the power goes I simply cut my main then fire up the genny, result is the same but the cost is nil. I'm not an ijut therefore I KNOW to turn off my power. My power doesn't go out regular enough nor do I need a back up supply for medical reasons, I simply want it so I don't miss HOUSE on Tuesday night! No need to go to all the expense of having transfer switch for an occasional power outage. Its not like my genny is going to come on all by itself anyway, someone has to go pull it out of the garage, wheel it around back, cut the main and plug in the genny.
My electrician installed the outlet (at the time I didn't realize how easy installing a breaker was) and to think that cost me 75 bucks! He also TOLD me how to go about installing my genny the proper way. Hell I hated having an extension cord running through my door. So, I am viloating no codes nor am I hazzarding a linemans life in this way. My house has two seperate panels (one for the shop and one for the house) plus a knife switch box for the main supply.
Safety is the concern here first and foremost, the key to my genny is hangin on the knife switch box, so there is no way I can run the genny without first throwing that main..
THROW THE MAIN, notice how many times I brought that up, IT IMPORTANT!!!!
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That is wonderful that you know "to turn the power off"..... But what if you have someone over and they don't know, or you sell the house and the new owners don't understand.
The Codes in North America are written to ensure the safety of everyone involved. It is fine that it works, but when it is not done properly, people can get seriously injured or even KILLED!
If for some reason the power supplied by your generator is introduced to your homes main electrical wiring and then manages to travel to your panel, through the main breaker and back feed your power utilities system..... people can get KILLED!
YES, I UNDERSTAND THAT YOU KNOW! But you have many people around you that don't... and we are all human which means that sometimes we forget....
It is not worth taking the chance of taking a life. If it is done right the first time, everyone is better off!
Sorry if this has come off as a Rant, but electricity is dangerous and if mis-handled it can injure and kill. Any and all work should be done under the strict guidance of a qualified tradesperson. And all work should be inspected by your local inspection authority. Their job is to make sure that everything and therefore everyone is SAFE!
AS TO THE ORIGINAL POST:
I believe that you have found the best option for your situation. Any system that ensures that the main breaker is turned off prior to the generator breaker being turned on (so that anyone can operate it correctly) is the way to go. After that, it comes down to load management as the size of the generator can only handle so many things at once.
In addition, I think the process you have followed in making the decision is what should be done in all occasions. Educate yourself and if you find it difficult to assess the information that you receive, contact independant individuals who have no vested interest in giving you advice in one direction or another and have them explain the information that you have received.
Best of Luck on your project.
Glen
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Who is going to be at my house when the power goes out? If I'm not there then sure as hell no one else is going to worrying about the power! If I sell the house, the genny goes with me, the outlet can stay, that way if the new owners decide to listen to a radio outback, well what do ya know theres an outlet out ther, and guess wht, IT Works, its actually transmitting power throught it. Hmmm, hoodathunkit!
My genny is a portable emergency power unit, it IS NOT hooked into the house ready and on standby, it is in my garage. If the power goes out, I< I take the genny out throw my main fire it up and I have power. Whats so hard to understand!
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Shopdog wrote:

Be aware that it is becoming common practice to pull meters on any home that declines a check on the connection of a generator during storm recovery and individual services are the last thing restored. So keep a lot of fuel on hand as you may be in for a long outage. The cost of a laboratory listed interlock kit is around sixty dollars. A weatherproof generator inlet is around eighty dollars. So you saved maybe two hundred dollars by using a suicide cord. The International Brotherhood of Electrical Workers (IBEW) is committed to seeking manslaughter indictments against anyone who causes the death of an outside wireman by back feeding receptacle outlets. But of course you'll never make a mistake!
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
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Its too bad that individuals like Shopdog just don't understand that when it comes to electricity "rules are NOT" made to be broken.
These types just don't get the fact that we are all human and we can make mistakes. Instead of spending a few more bucks to make 100% certain that no one can get hurt, they find ways to cheat the system and then when someone does get hurt, they say "Oops I didn't realize that could happen!"
Wonder if this guy has a hot tub without GFCI protection, "cause GFCI's are only a money grab for manufacturers" "Electricity doesn't kill people, people kill people!"

This is exactly the problem. You are backfeeding the house panel through your existing electrical system. If you or someone else forgets to throw the main breaker off, someone will get killed. In addition, in order to do this, your extension cord has an ILLEGAL end on it that is live --- and it can kill someone too if not disconnected. IF YOU DON'T BELIEVE US ELECTRICIANS, CHECK WITH YOUR LOCAL INSPECTOR!
Again Sorry about the Rant,
For anyone reading this ---- PLEASE, PLEASE, PLEASE ---- Just follow the correct rules. It isn't worth someone else getting seriously hurt or killed over such a simple thing as electrical safety. The rules are set out for a reason --- usually because someone has died from the result of improper procedure.
If you have any doubts about what you are doing seek the advice of a qualified tradesperson or the local inspector to get the direction you need to have the work done properly.
What Shopdog has done is unsafe and if inspected by a local inspector, he would have serious issues to deal with! There is no need for it --- especially with the newer relatively inexpensive solutions available.
Hopefully the IBEW, the local power supply company or the local inspectors will find these people who take shortcuts before someone gets hurt....
Glen
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You just brought up another reason why the interlock switch appears to be my best option: the size of the generator.
Right now I have a 5500w but my daughter is building a home here and has already indicated a desire to have her own generator as well. She's having her house pre-wired for this purpose. So, I will eventually give her my 5500w gen and purchase a higher wattage replacement.
Had i decided on a 6- or 8- circuit transfer switch, I probably would not have been able to take advantage of the increased gen power of the replacement unit unless I had switched out the 6- or 8-circuit for a higher one (or just added a second 6- or 8-circuit switch) to allow for higher energy loads. With the interlock switch, I can increase my gen size to wnything I want and not worry about the panel, since the intelrock allows me to use any combination of loads any gen I use will tolerate.
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You are exactly right, with the route you have chosen, it is very easy to upgrade your system for a larger generator.
A little preplanning and a few questions go a long way.
Enjoy!
Glen
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On 05/25/06 12:37 pm Shopdog wrote:

Isn't a cord like this known as a "widow maker"? -- and for good reason.
Perce
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Boy, you sure did get a lot of contracictory information. See a couple of my inline comments below, too. I am NOT suggesting this is a do it yourslef job unless you are qualified. I purchased an Emergen Transfer Switch and installed it. I bought a length of appropriate cable and the conntectors and built a cable to connect the generator to the transfer switch. The outdoor "disconnect" is the plug at the generator. The cord comes in thru the wall and plugs into the Transfer switch. The transfer switch has ten switches (breakers): The are wired as follows: One 220 pair for 1 HP well pump (that's a ganged set of 2 brkrs used). One for the furnace, None for AC; power problems here are always winter. One for water heater, set of kitchen outlets, and ceiling lights in two rooms. One for lights in three other rooms One for outlets in main living areas; living room, bedroom, etc. One for computer room. Don't run your computer off a generator unless you have a power conditioner. The rest go to whatever was handy in the panel: lights, outlets for coffeemaker, microwave, gas stove, things like that.
The big advantage of a transfer switch is that it allows you to turn things on or off at will, thus minimizing what's energized at any one time, plus it makes it impossible to feed power back into the power lines outside. Each switch on it has three positions: Power from generator, all OFF, power from outdoor lines.
In our case, the only time we have any problems is if the well pump and say the freezer or fridge turn on at the same time, or the furnace fan joins in. The turn-on surges are high enough that they pull the power down so far the generator really lugs down hard to start them. That's very hard on electric motors and puts excessive wear and tear on the generator. So far we've never popped a breaker on the genset, but that's because we're careful about which switches we turn on at the same time. The Transfer Switch breakers are a set of ganged 25A for 220, plus 4 20A, and the rest 30A. It's oversized a tad at 7500W capability, but that was my choice in order to be able to control various things. In general, you want your genset loaded to about half of its rating or less for extended periods of time. Beyond that you are causing excessinve wear and tear on them. There ARE better generators, but one pays a fortune for them.
It passed code inspection first time with not even any minor recommendations other than I hadn't yet fully plugged the hole where the cord comes trhu the wall into the house. But, I checked with code enforcement BEFORE I did the job, and even supplied them with a detailed schematic and load estimates. A contractor would take care of all that.
My only regret is that I wish I'd gotten a deisel genset. We usually get at least one 3 day outage per winter (most are less) and keeping enough gasoline around and stored for that purpose is kind of a hassle and requires storage planning to keep the fire dept. happy. I checked into a large storage tank for the gas, but that's incredibly expensive with all the codes and stuff it has to pass: You can't just set it down and fill it, it turned out. So, if/when this genset bites the bullet, I'll make sure the next one is a diesel set - fuel storage is much less dangerous.
Any further questions, just ask; I'll help where I can. I'm not an installer, not an electrical contractor, nor any "expert": I'm an electrical engineer and know how to read and keep up with what the codes require is all, plus I enjoy do it yourself jobs as a rule. One inspector, that was out for a wiring change I made for our foster care bedroom, laughed at the neatness of my breaker box: I'm sort of a neat freak. But, I can glance into it, and tell you exactly which wire in all that mess of 40 breakrs goes to which fitting; seldom possible with most installations. Made wiring the transfer switch a LOT easier! Contractors logically can't spend the time to do that sort of thing; nothing special otherwise <g>.
HTH,
Pop
There are lots of links on the subject; these may help you understand some of it: http://www.nbmc.com/emergen/index.html http://members.rennlist.org/warren/generator.html http://www.money-resource-online.info/how-do-i-wire-a-manual-transfer-switch.html
PRNole wrote:

-- REasonable product, will handle furnace, fridge, lights & a 1 HP well pump per my own experience.

-- Decent price, IMO IFF it includes everything from the plug that goes into the generator to a fully functional Transfer Switch.

-- Unless you confused him, put this one in the round file. What was the reason given? Totally incompetent unless there are missing facts.

-- a. 5500W isn't enough to run your entire house. You'll have to decide what you NEED to run and go from there. You'd have to run around each time making sure everything was turned off that was going to overload the gennie. With an interlock, you have no way to "sequence" the load to the generator: ALL electric motors, etc, would come on at the same time and probably pop the breakers (or worse) of the generator. b. It would still have to be a transfer switch "type" in order to meet safety and code requirements. c. Your local code enforcement officer can give you the best info in this are.

-- Never say never, but ... a standard interlock, I don't think, will not meet the codes and/or isn't really the right way to do it, unless it's specifically designed to function as a transfer switch. Besides, see my comments in your #4 above.

-- Either there was a lot of confusion running around or you have misheard things. I would also recommend against an interlock, and DID opt for the transfer switch. It works well.

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On Thu, 25 May 2006 17:32:59 GMT, Pop wrote:

You might also consider one like mine - tri-fuel. It'll burn gasoline, propane or natural gas. If you have one of the latter two, you don't have to worry about storage problems - or a tank for diesel storage. Only have to install a hookup from your current gas line - or hook it to a separate propane tank if you like.
Later, Mike (substitute strickland in the obvious location to reply directly) ----------------------------------- snipped-for-privacy@bellsouth.net
Please send all email as text - HTML is too hard to decipher as text.
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Michael Strickland wrote:

Nat. gas is a very poor choice for backup power as it is often interrupted along with the utility power. A backup generator needs to have an on-site fuel supply to be reliable.
That said, if you have a big "hot dog" LP tank or an oil (aka diesel) tank for your normal needs then that is the primary fuel to look at.
Gasoline is a poor choice due to the issues with storing any significant amount or storing it for very long. It's ok for short duration since you can siphon fuel for an extra vehicle for a few days. Don't siphon from your only vehicle though.
Pete C.
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PRNole wrote:

Will work just fine, but limits you to having to select which six circuits will have backup capability.

May or not be a reasonable cost depending on the installation issues. If you have a fairly new panel surface mounted in a basement or garage with easy access and plenty of space for the new switch it's probably pretty overpriced. If however you have a hideously old panel flush mounted in an old stucco's wall in a filthy, cramped, spider infested basement with no room for the transfer panel then the price might be good. Point is that parts are pretty well known, but time and labor could vary tremendously.

Utterly false, any 120V or 120/240V 60HZ (US) generator can work with a manual transfer switch. Some really small ones it would be pointless with since they couldn't handle more than a refrigerator (if that) and an extension cord would be just as easy.
A 5,500W generator is quite adequate to power a "normal" 1,500-2,000 sq. ft. home just fine during a power failure. It can power a well pump, gas or oil furnace (no electric heat though), refrigerator, small window A/C (no central), lights, TV, etc.

The Square D interlock kit is a very good and inexpensive option that gives you good flexibility and also an easy upgrade path if you get a larger generator down the road. Since it interlocks the main breaker in the panel with any standard two pole breaker in the 2/4 position of the panel it can accommodate generator feeds up to the maximum branch circuit breaker size of the panel which is 125A (30KW).
I just installed the Square D kit ($30) along with a new Square D QO 200A panel in my house. If you have a Square D panel it's a great option. I would never install a Square D interlock kit on a non Square D panel however as it would void all approvals and testing that the kit has passed. If there is a similar GE kit made for your panel use it to maintain the approvals.

The interlock kits *are* manual transfer switches, indeed they are closer to the "real" large transfer switches that switch the feed before the panel than the little six circuit panels are. The little six circuit panels are basically six tiny little 20A transfer switches vs. one large one.

The interlock kits are quite new so that probably explains what you were told in #5. Old electricians are leery of new stuff and prefer to stick with what they are familiar with.
The little six circuit transfer switches are still a lot newer than the "real" large single transfer switches, but they've been around long enough for electricians to get comfortable with them. When they first showed up on the market you would have heard similar comments to #5.
Number 3 is out in left field and is either a crotchety old fart who doesn't want to deal with a small job, or someone who wants to sell you one of the much more expensive packaged standby generator / automatic transfer switch units like the Guardian units sold a Depot and Lowe's (nothing wrong with those packages though, just more expensive).
Number 4 is entirely correct that the Square D interlock kit is a good option, but should not be recommending installing a Square D kit on a GE panel.
For reference here is the link to the Square D product announcement for the interlock kits:
http://ecatalog.squared.com/techlib/docdetail.cfm?oid 00892680126e4f
Pete C.

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The sensors are built into the thermostat;they are thermistors;change resistance with changes in temperature.They are a tiny seed-sized (~2mm dia.)component with two fine wires coming out of them.
--
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With a transfer panel you wont have the possibility of making a mistake with the wrong circuits open. The 2 watt meters allow you to know the load. A 6 circuit should cost 4-500 installed complete, the Generac kit even has the exterior box, cable , sockets and plugs, it is pre wired for HO instalation.
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m Ransley wrote:

Knowing the exact load is far less important than you might think, knowing what is on which circuit is far more important. If you accidentally overload the generator you just pop a circuit breaker on it or worst case stall it, annoying, but not a big deal.
The best thing you can do is map out every circuit in the panel and what is on it normally. In my case I have a full CAD print of the house layout with every outlet, appliance and fixture indicated along with the circuit number it's on. Add in the data for the normal current draw on that circuit and it will make load management very easy.
Generally you'll want to leave all of the lighting circuits on since they typically represent very little load, particularly if you use a lot of CF type lamps. The refrigerator and the circuit that covers your TV would also typically be left on. Only large loads like well pumps, furnaces and window A/C generally require load management.
Pete C.
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Well, I already had a detailed map of all the breakers in my panel, detailing exactly what you suggest, down to the specific location of outlets, whether they have any appliance or fixture plugged into them, etc. Of course, I also have each breaker identified according to the grid. Since reading your post, I've added the individual loads to the master grid map I keep on paper (and my PC).
The experience I've had managing loads with this generator, when I ran several extension power cords into the house, is that I preferred to use the following circuits:
1. Below ground well pump 2. Above ground (house) pump 3. Refrigerator 4. TV outets 5. Computer outlets 6. One outlet in kitchen for 1 x 100W bulb on one small lamp (clip-on) 7. One outlet in master bedroom for 1 x 100W bulb on one nightstand lamp 8. One outlet in another bedroom for 100W bulb on another nightstand lamp 9. Two portable fans
The well pumps never presented a problem, for we scheduled all water use for the same time period while avoiding use of other appliances at same time. Of course, we avoided washing/drying clothes until after power was restored.
I suffered for 12 days without power while using the above loads with the current generator I have.
The main attraction of the interlock switch is that I can simply go from room to room, or upstairs, etc., and simply turn off lights (or appliances) in rooms not being used, then turning on needed lights (or appliances) in the room breng occupied, etc. Being able to use the overhead fans we have in each room is also attractive.
BTW, the lowest estimate I have received for a contractor to supply and install a 6-circuit transfer switch was $600. One other contractor quoted me 3 x that amount.
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Does your unit have 240 out, then a 6 circuit 2 watt meter transfer panel is safest, you can see whats being used and balance it easily. A complete prewired Generac transfer kit at lowes might be 2-300$ and take 2-4 hrs install, mine was free at lowes with a 5500w Generac Generator, if it doesnt have 240 out call the manufacturer to see what they recomend
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