Crossover switch? Cutoff switch?

What's the switch called that you use to cut a circuit over from street 'lectricity to a generator?

And do they come in a little 15- or 20-amp version?

I just lost most of today's opportunity to work to a power outage (big windstorm today), and spent my down-time buying a generator. I can just toss an extension cord through the window of my office to the generator, but it'd be nice to connect it to my office plugs instead.

Reply to
Tim Wescott
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Transfer Switch.

Reply to
Michael A. Terrell

It is known as a "Transfer Switch" Eric

Reply to
etpm

Transfer switch. Not something I recommend to anyone these days in most cases. Look for an interlock kit to match your electrical panel. Interlock kits are available for most panels now, in many cases OEM interlock kits, and they are less expensive and more versatile than a traditional transfer switch. I use a Square D interlock kit on my 200A QO panel with a 30A generator feed breaker. It works very well and the OEM interlock kit was ~$60.

Reply to
Pete C.

Ditto, I have a whole house generator and interlock kit, works great for me.

i
Reply to
Ignoramus12490

On 11/12/2014 6:26 PM, Pete C. wrote: ... I use a Square D interlock kit on my 200A

Umm ... the GE's that I found were $150. Why should they be so much more? Anyhow, I just use the old turn-off-the-main-breaker & back feed through the welder circuit.

Reply to
Bob Engelhardt

Be prepared to catch a ration of shit for doing it that way . I do it the same thru the shop subpanel , and every time it comes up I get accused of trying to fry a lineman or something . Hmm , I was just thinking , if a guy wired them up right a set of lights could not only tell when the power came back on but could let you synchronize with the grid for uninterrupted service .

Reply to
Terry Coombs

Even the cheaper ones are an awful lot of money for a small sheet-metal stamping.

Reply to
Jim Wilkins

They can spew that nonsense, but that's all it is. It is physically impossible for your little generator to "fry a lineman" unless that lineman violates his safety procedures. They *must* test and ground every circuit conductor before they are allowed to handle it without insulating gloves, so it is simply not possible for them to be harmed by your generator unless *they are at fault*.

Reply to
Pete C.

I can agree they must violate safety procedures to be harmed . Beside the fact that if the line is still intact to other's houses my genset will trip out immediately on overload if I'm still connected to the line feed .

Reply to
Terry Coombs

Correction to the end of that last statement:

"so it is simply not possible for them to be harmed by your generator unless *both they and you are at fault*."

People are still liable for their actions, so charging a dead power line with their generator is strongly recommended against.

Reply to
Larry Jaques

I've never liked dogs.

Reply to
mogulah

I do the same thing. (Ducks head as people scream at me.) And if I didn't turn off the mains power wouldn't my generator be trying to power up the en tire neighborhood? What I'd really like is a little light to come on and t ell me when mains power is back on.

George H.

Reply to
ggherold

George , see my post above . There is a way to wire up lights so you'll know when the power is back on - and have them usable to synch your genset to the line so you can make the switch back to "shore power" without interrupting your wife on her computer while she's surfing for new (snow)shoes .

Reply to
Terry Coombs

Mount a handy-box right next to the breaker box. Use a short or offset nipple. Get a fused outlet cover for the box:

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Try assembling the two first. That combination doesn't always fit together well. The fuse hot lead/wire likes to bump into the nipple. So look over the clearance good before taking a knock-out out. It can be done with the right combination :)

Very carefully route a 12 gauge wire from the new fuse cover/outlet over to one of the mains cable lugs. This has to be someplace before the main breaker. Route/attach a neutral over to the neutral bar. When you have the new cover/box all assembled, ready to go carefully loosen the main lug and slip the #12 wire in along with the main lead. BE REALLY CAREFUL IF YOUR MAINS ARE STILL HOT! I did this for a living, not a big deal to me. Either that or you'll have to wait for a power failure, pull the meter off... Tighten the lug back up and then tug on the leads some to make sure they aren't loose. It will most likely go poof if something ever goes wrong with the #12 wire (pinched, rub through...). So you don't want that to happen. Put in a 20amp fuse. Now this plug will always be connected to the outside line, even when the main breaker is off. Plus you get a handy little outlet by the breaker panel.

Plug something into the outlet, light, noise maker, radio... whenever you have the main off and want to know when the main line comes on again...

Reply to
Leon Fisk

That's my take on it. And it's not only the 5 or 6 houses sharing the pole pig with you, but the pole pig itself. You'd be trying to energize the pole pig secondary, which would energize the primary and try to energize all the pole pigs on that 1200v (?) line, etc. In other words, the service line to your house would look like a dead short to your generator. Also, with the internal impedance of the generator, its output voltage would drop way down during the time it takes to trip its breaker.

Not that I'm going to be complacent about opening my main breaker, but the risk if I don't is minimal.

Bob

Reply to
Bob Engelhardt

That's all it is? It just prevents your back-feed breaker from being on unless the main breaker is off?

Reply to
Bob Engelhardt

Thanks Leon, Since this only happens once every few years it's not that big of a deal. I've got a big knife switch on the side of my house where the mains comes in and this is where I switch it off.

George H.

Reply to
ggherold

Bob Engelhardt fired this volley in news: snipped-for-privacy@news6.newsguy.com:

Yeah... I have 'basic' mains on the line and the genset, and clear labels and written instructions hanging inside the breaker box. There's more to cut off besides JUST the main... the generator can't handle the entire load (like AC, water heater, etc). Some items are 'optional', depending upon what else is on. It's all there in the sheet -- just like "Green Acres" .

Even if one were to cut over the genset before switching off the main, all it would do is trip (either the specific main, or the breaker on the genset). LLoyd

Reply to
Lloyd E. Sponenburgh

Bob Engelhardt fired this volley in news: snipped-for-privacy@news6.newsguy.com:

That's all... just a purely mechanical interlock. L

Reply to
Lloyd E. Sponenburgh

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