Which 20kw whole house generator would you recommend and why

[spruce232]

this is wrong ^^^ The neutral gets bonded in the transfer switch ( first means of disconnect ) and thats it. So what hr3 is saying is that if you install a sub panel on the same "backer board" you would bond the neutral again, which is completely wrong and againt code. I wont argue the facts on here, You may want to consult a local Electrician.

<<< local 8 IBEW J.I.W. for the past 21 years.

 

[grsthegreat]

i agree that ONLY the initial panel (the generator transfer switch) should have the neutral and ground bonded together. The 200 amp panle is supposed to have isolated grounds. Easy to do, just add a metal ground bus or two and move the bare wires over.

remove the bond wire off of the isolated neutral bus that exists...and your done.

28 years electrician and electrical contractor

it doesnt matter if there on the same panelboard or not. after the 1st disconnecting means, everything else is considered a sub-panel.

 

[pclausen]

Ok, I installed a separate ground bar in the 200A panel. I moved all the circuit grounds over to it. I moved the ground from the transfer switch over to it.

However, I did not yet remove the neutral bonding strap, nor move the ground rod wire over (green arrows in picture below).

The reason is that there is a 50A circuit that powers an oven/microwave combo (red arrow in picture below). If I float neutral, those ovens will loose ground, no?

I went to connect the generator to the house ground rod, but it is not exposed, but rather buried somewhere underneath this 6x6 landscape post that has concrete poured up against it. Can I just clamp onto one of the wires going down in the ground (red arrow)?

Same question goes for the transfer switch. It it not yet connected directly to the house ground rod for the same reason.

If there was an inspector involved, he would probably have me jackhammer up the concrete pad and remove the 6x6 and connect directly to the rod.

 

[techman]

Your grounds will not be floating. They will still be connected to the neutral (bonded) in the transfer switch box instead of the breaker box. There should be no potential difference.

paul

 

[pclausen]

Thanks Paul. Just wanted to make sure it was ok for that one circuit to not have a direct ground connection. Did a little research, and up to about 15 years ago, it was common for 220V appliances to only have 3-wires, which worked fine since neutral and ground terminated to the same location.

On the other hand, I noticed that both the 100A circuit to the shop sub-panel and 60A circuit to the pool sub-panel, are both 4-wire. I guess being that they are detached buildings is the reason why, even on a house built in 1982.

 

[grsthegreat]

Thanks Paul. Just wanted to make sure it was OK for that one circuit to not have a direct ground connection. Did a little research, and up to about 15 years ago, it was common for WV appliances to only have 3-wires, which worked fine since neutral and ground terminated to the same location.

On the other hand, I noticed that both the 100A circuit to the shop sub-panel and 60A circuit to the pool sub-panel, are both 4-wire. I guess being that they are detached buildings is the reason why, even on a house built in 1982.

here in N Idaho, the inspectors require us to drive a separate ground rod at PERMANENTLY installed generator...the way you did. so yours should be just fine now.

 

[hr3]

this is wrong ^^^ The neutral gets bonded in the transfer switch ( first means of disconnect ) and thats it. So what hr3 is saying is that if you install a sub panel on the same "backer board" you would bond the neutral again, which is completely wrong and againt code. I wont argue the facts on here, You may want to consult a local Electrician.

<<< local 8 IBEW J.I.W. for the past 21 years.

Would you agree that what he has in his pictures goes along with the defination in the code book as " Service Equipment" --- " Quote" The necessary equipment, usually consisting of a circuit breaker(s) or switche(s) and fuse(s) and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of supply., End "Quote..

Ooo a question.. In the code book where do you find "Subpanel"..

 

[pclausen]

here in N Idaho, the inspectors require us to drive a separate ground rod at PERMANENTLY installed generator...the way you did. so yours should be just fine now.

Good deal. I was wondering if that was not allowed/recommended, how come the Generac service tech that maintained the 15kw unit for years never mentioned anything about it.

 

[hr3]

Here in Maine we go by the 2011 code that doesn't allow a ground rod at the generator... As explained to me if something Catastrophic should happen there could be potentional between the two rods..Like the power comes back on and somehow the service goes to ground and the generator has the same problem at the same time.. I know it's a one in a million..

 

[pclausen]

But the generator ground also goes to the transfer switch ground bus, which in turn is connected to the house ground and its rod. :confused2: