Hello, My questions are related to connecting a portable generator to my main service panel. I want to make clear that even though I do have some electrical knowledge, I am not a qualified electrician and do NOT plan to do this project myself, but rather will be hiring a qualified electrician to do it for me. However, I would like to purchase everything I need in advance before I contact an electrician, and to mount any devices that I need and then let the electrician hook all the wiring up. I want my system to be sized up to 12,000 watts.
Items I currently have are as follows.............
1) 50 amp 3 prong inlet box to connect the generator to the house.
2) 30 feet of #6/3 wire (w/gnd.) to connect the inlet box to the transfer switch.
3) Mechanical interlock kit for main service panel.
I would like to purcahse a 12,000 watt generator. The generator I have in mind will have a neutral/ground bond with GFI protected 120V outlets, a 30 amp 120v/240v three prong outlet that is not GFI protected, and one heavy duty 50 amp 120v/240v four prong outlet that is also not GFI protected. I understand that code requires that there is NOT more than one neutral/ground bond in the system.
So, my questions are as follows.................
1) Do I need a 3 pole maunal transfer switch that has a pole reserved for switching off the neutral? Does a 3 pole transfer switch do this? Or does it really break the neutral-to-ground connection in the service panel? I have read some forums that say if the outlets in the generator are not GFI protected, then I don't need to switch off the neutral in the service panel to prevent a ground loop from tripping the generator's GFI circuits. But I believe it still does need to do this to prevent a ground wire from carrying current other than fault current, which is obviously a safety issue. If this is the case, can anyone suggest a compatible transfer switch for this?
2) Does a 2 pole 50 amp breaker (which would be interlocked by the mechanical interlock kit to allow only the 50 amp breaker, or the service panel main breaker to be switched on at a given time) need to be installed in the main service panel to be wired back to the transfer switch for feeding the two 120v busses in the service panel from the generator?
3) Is the 50 amp three prong inlet box the correct type of inlet box for this application? I ask this because the 50 amp outlet on the generator is a four prong, and I have found extension cords that run between the generator and inlet box that have a four prong male connector on one end, and a 3 prong female connector on the other. I assume the 3 prongs in the inlet box are two 120v hot legs, and one neutral. Why does it not also carry the ground connection through?
It would really help if you could verify what componets that I have mentioned I either need or don't need, and why. Thank you for any advice you can offer.
Items I currently have are as follows.............
1) 50 amp 3 prong inlet box to connect the generator to the house.
2) 30 feet of #6/3 wire (w/gnd.) to connect the inlet box to the transfer switch.
3) Mechanical interlock kit for main service panel.
I would like to purcahse a 12,000 watt generator. The generator I have in mind will have a neutral/ground bond with GFI protected 120V outlets, a 30 amp 120v/240v three prong outlet that is not GFI protected, and one heavy duty 50 amp 120v/240v four prong outlet that is also not GFI protected. I understand that code requires that there is NOT more than one neutral/ground bond in the system.
So, my questions are as follows.................
1) Do I need a 3 pole maunal transfer switch that has a pole reserved for switching off the neutral? Does a 3 pole transfer switch do this? Or does it really break the neutral-to-ground connection in the service panel? I have read some forums that say if the outlets in the generator are not GFI protected, then I don't need to switch off the neutral in the service panel to prevent a ground loop from tripping the generator's GFI circuits. But I believe it still does need to do this to prevent a ground wire from carrying current other than fault current, which is obviously a safety issue. If this is the case, can anyone suggest a compatible transfer switch for this?
2) Does a 2 pole 50 amp breaker (which would be interlocked by the mechanical interlock kit to allow only the 50 amp breaker, or the service panel main breaker to be switched on at a given time) need to be installed in the main service panel to be wired back to the transfer switch for feeding the two 120v busses in the service panel from the generator?
3) Is the 50 amp three prong inlet box the correct type of inlet box for this application? I ask this because the 50 amp outlet on the generator is a four prong, and I have found extension cords that run between the generator and inlet box that have a four prong male connector on one end, and a 3 prong female connector on the other. I assume the 3 prongs in the inlet box are two 120v hot legs, and one neutral. Why does it not also carry the ground connection through?
It would really help if you could verify what componets that I have mentioned I either need or don't need, and why. Thank you for any advice you can offer.
Last edited:
