Buying a generator for house.What should I expect to pay an electrican?

[sangerwaker]

Re: Buying a generator for house.What should I expect to pay an electrican?

HUTS
I agree that backfeeding to the power lines is VERY bad, but you are incorrect regarding the direction of current flow and a breaker tripping. A circuit breaker will trip no matter the current flow. Look at a 100 amp main breaker load center from any manufacturer. The main breaker is a standard 2 pole 100 amp back fed on to the bus bars.

 

[bigdee]

Re: Buying a generator for house.What should I expect to pay an electrican?

HUTS
I agree that backfeeding to the power lines is VERY bad, but you are incorrect regarding the direction of current flow and a breaker tripping. A circuit breaker will trip no matter the current flow. Look at a 100 amp main breaker load center from any manufacturer. The main breaker is a standard 2 pole 100 amp back fed on to the bus bars.

X2 another example of back-feeding is a 100 amp generator transfer switch. It uses 2 100 amp breakers opposite each other and a tie bar connected to the handle of each breaker so when one is on the other is off. One breaker is backfed from the generator and the other breaker is backfed from the utility service...the buss bars are connected to the main house panel.

 

[hungupthespikes]

Re: Buying a generator for house.What should I expect to pay an electrican?

HUTS
I agree that backfeeding to the power lines is VERY bad, but you are incorrect regarding the direction of current flow and a breaker tripping. A circuit breaker will trip no matter the current flow. Look at a 100 amp main breaker load center from any manufacturer. The main breaker is a standard 2 pole 100 amp back fed on to the bus bars.

Yea the breaker should protect the wire, but the breaker is not designed to protect when it's being feed from the wrong side. It's to protect the wire down line (beyond the breaker, not up the line, power coming in.

Sorry sangerwaker, I wasn't very clear.

We're not talking about a main breaker, it's a 15 amp circuit breaker, same principle, lead/solder melts or metal bows and the arm springs, breaking contact. It's just not designed the same or near as heavy duty as a main. Also a house/building is protected from the box to the weather head, after that it's ambient air, or buried, so there is no other harm if the wires burn.

The feeding thru an outlet, it is not hard wired like a breaker, it's just a plug. Then your running a feed thru interior walls on romex, not conduit, so no protection for the building.

Feeding into a 15 amp outlet. The outlet just doesn't stand a chance against 25amp generator. When it fails, the house breaker will never see the amperage. Even if it could, it is powerless to stop the meltdown caused by the generator to the outlet or the wire.
Even if there are 20 amp breakers at the house and generator and a 25 amp outlet, there is still no protection (conduit) inside of the house/building on a feed line.

Just don't backfeed it's unsafe/illegal on several levels.
I'm done :lol:
huts

 

[bruceb58]

Re: Buying a generator for house.What should I expect to pay an electrican?

Feeding into a 15 amp outlet. The outlet just doesn't stand a chance against 25amp generator.

I still think the 15A breaker that protects that circuit would trip at 15A. However, the outlet could see 25A if there are loads on that particular branch that equal 10A .

Not that I think this is a good idea to do!

 

[bigdee]

Re: Buying a generator for house.What should I expect to pay an electrican?

Sorry sangerwaker, I wasn't very clear.

We're not talking about a main breaker, it's a 15 amp circuit breaker, same principle, lead/solder melts or metal bows and the arm springs, breaking contact. It's just not designed the same or near as heavy duty as a main. Also a house/building is protected from the box to the weather head, after that it's ambient air, or buried, so there is no other harm if the wires burn.

The feeding thru an outlet, it is not hard wired like a breaker, it's just a plug. Then your running a feed thru interior walls on romex, not conduit, so no protection for the building.

Feeding into a 15 amp outlet. The outlet just doesn't stand a chance against 25amp generator. When it fails, the house breaker will never see the amperage. Even if it could, it is powerless to stop the meltdown caused by the generator to the outlet or the wire.
Even if there are 20 amp breakers at the house and generator and a 25 amp outlet, there is still no protection (conduit) inside of the house/building on a feed line.

Just don't backfeed it's unsafe/illegal on several levels.
I'm done :lol:
huts

15 amps or 100 amps makes no difference whether it is back-fed or not, it will perform the same. They make 15,20,30,40 amp transfer switches and they all use standard double pole breakers and are back-fed.

 

[joed]

Re: Buying a generator for house.What should I expect to pay an electrican?

The breaker will trip if it sees 15 amps going either way. However by plugging the generator into a receptacle with a suicide cord and turning off all the breakers in the panel it is possible to overload the circuit. If you plug too many thing into the one branch circuit the breaker will not see the current even if it is on. The current will remain on the wiring within the branch and only the generators breaker will protect it.

Suicide cords are dangerous and illegal. We do not even discuss them on electrical forums because someone might get an idea they never thought of.