Interested in installing (or having installed) a generator interlock or transfer switch for my home. Main panel is 200A, Square D Homeline.
I like the interlock setup as opposed to a transfer switch because it gives me more flexibility to pick and choose circuits I might want to run off my 6000W generator in an emergency. They are available for this panel, both from Square D and the alternative company that makes them.
In the first two right hand slots of the panel, I have a breaker (2x40A) for an old 220 range which is no longer used (range has been converted to gas). The generator tie-in can go here.
I'd like to stage my generator on my back porch when the power is out (a bit more secure and a little overhead cover from the roof line). Unfortunately, this is on the other side of the house (50') from my panel.
I was wondering if I can use the existing 220 range wiring (BX) to connect my generator to the panel? The old range wiring ends on the other side of my porch. Would there be any issues with loss over this distance (50')?
As long as the range circuit was wired with 8-3 or 6-3 with ground, and you install a double pole 30A breaker, and a 30A power inlet box, and the interlock is properly installed (these interlocks are normally a full replacement dead-front with the interlock mechanism permanently riveted on, and require the generator breaker to be installed in the 1-3 or 2-4 position), then you should not have a problem. With #8 or #6 cable, you shouldn't have voltage drop issues over that distance. If the cable is two conductor+ground, or three conductor with no ground, then you can not use it.
I'm not a big fan of this type of arrangement. Mainly because it gives you no indication of when the power comes back on, since the main breaker is pulled while the generator is running. It also requires you to shut off all the other breakers to prevent overloading, and it would be tempting to keep turning on 'just one more' until you stall (or smoke) the generator. A 'selected circuit' transfer panel doesn't require the main to be pulled, therefore you can keep a nightlight or something in a dead outlet to let you know the power is back on.
I'd like to stage my generator on my back porch when the power is out (a bit more secure and a little overhead cover from the roof
This may be unsafe because of CO build up under the overhead and may be a building code violation because of distance to doors and windows.
was wondering if I can use the existing 220 range wiring (BX) to connect my generator to the panel? The old range wiring ends on the other side of my porch.
If it is #8, three conductor (red, white, black., and a type of AC (armored cable) with bonding strap or a ground wire yes.
Note at 6000 watt #10 could be used with a 30a breaker.
Originally Posted by ray2047
This may be unsafe because of CO build up under the overhead and may be a building code violation because of distance to doors and windows.
Agreed, my patio is adjacent to the porch so I could stage it there instead. Seems the mfg recommendation is to keep it dry, if possible, but it will more than likely be used during rain events.
Confirmed that it's three conductor armored cable with NO ground wire. BIG gauge, not sure exactly what size from looking at it (bigger than 10, I believe).
You could get one of those little rubbermaid garbage can enclosures (where it has the two doors in the front and flip up top) and set it off the porch..
Originally Posted by jogordo
Confirmed that it's three conductor armored cable with NO ground wire. BIG gauge, not sure exactly what size from looking at it (bigger than 10, I believe).
Then its a no-go.. You must have the ground wire, and you can not use the armor jacket as a ground. You will have to run a new cable.
If it was on a 40A breaker, then it has to be at least #8. It is not uncommon for range circuits to be wired with #6 to handle up to 50A. #6 conductors are about the thickness of a pencil.
Have you uncoiled the armor a little to see if there is a bonding wire that was simply cut flush?
Tags: generator, interlock, install, ground wire, range wiring, three conductor, with ground, armored cable, armored cable with, cable with
