Question about detached garage/generator/transfer switch

[Quijote]

My detached garage is built. All that is left is the slab and running power to it.

The electrician will be here tomorrow to run power underground (100A sub-panel) to my garage. It will require about 130 feet.

Since I own a new, 7000 watt (continuous) generator, I'd prefer to have it live by the garage that is 100' away from the house for noise/convenience issues. I figure I would not have to roll it 120' (potentially through snow) near the house only to then hear it and annoy my neighbors (only woods at the back of the property by the garage).

Electrician said he would have to run two separate conduits - one to feed power to the garage from the grid, and another to feed power to the house from the generator. I'm ok with this as long as the cost to run the second conduit is not exorbitant.

He will also get me a quote on a transfer switch. I don't know what he is looking at, but it seems it gets pretty pricey the moment you go above 6 circuits. My house is a newer construction and there are tons of separate circuits, including the fact that my entire 2nd floor is run off a 100A sub-panel that lives there (in the laundry room). It's very convenient, but in this case, it may be a PITA, I think.

Just for the first floor I'll need (these are all separate circuits)
-Kitchen Fridge
-Basement (circuit where freezer is)
-Furnace (runs on piped natural gas)
-1st-floor air handler
-Kitchen lights
-Whichever kitchen circuit powers my gas range.
-Whichever circuits powers more lights in the first floor and TV/Cable
-The circuit next to the panel that powers FiOS (cable/phone/internet)
-Then there are the garage doors, smoke alarms (they do have battery back-up), front entrance lights, etc.

Then there are the circuits I'd want to use that run off the upstairs sub-panel:
-2nd floor air mover
-A circuit for some kind of upstairs lighting
-A circuit for some kind of upstairs outlets

If I'm very judicious I may just get away with a 10-circuit switch, but I still don't know how the upstairs sub-panel circuits get enabled without hoking up the whole 100A sub-panel circuit.

It ***** because all of this can be handled by 7000 watts, but there are just so many damn circuits.

I want to make sure I am semi-educated when I hear from the electrician.

Thoughts about any of this?

 

[snorky18]

I have NEVER understood why someone would go with an expensive manual transfer switch setup and all the required re-wiring and limit which circuits can be powered from the generator INSTEAD of just installing an IN-expensive interlock kit that allows you to power any circuit you want (as long as you have enough generator capacity.

(Unless of course they aren't allowed by your local codes, or not available for your main panel, then I'll give you a pass, and tell you go go look at generlink, which goes in your meter socket with no rewiring).

Good info here too:

http://www.garagejournal.com/forum/showthread.php?t=172620&showall=1

 

[Quijote]

Agreed. I much rather have this installed (link below). I'll bring it up to the contractor, but my town is SUPER picky and may not allow them.

http://www.interlockkit.com/faq.htm

 

[wyliesdiesels]

If the interlok isnt allowed, then the only other option besides a manual multi-circuit transfer switch, is a double pole double throw transfer switch that would go in between your meter socket and main service panel. If u have a meter main(meter socket and main service all in same panel) then a bunch of wiring would need to be done to accomadate the generator DPDT transfer switch.