Residential generator service rated transfer switches

[Squiggy969]

PA has just adopted the 2020 NEC. We are being told that if you install a service rated transfer switch that it must be installed outside next to the meter unless you install a disconnect instead and then feed the ATS inside. If you do not change the panel inside are other states requiring this? I know for service changes its required but is this considered a service change? Thanks

 

[AC\DC]

Yeah, cause there’s requirement to have your disconnects outside now I think Oregon got rid of it. I normally do that anyway but there’s been times when it’s been nice.

 

[qcroanoke]

Yeah, cause there’s requirement to have your disconnects outside now I think Oregon got rid of it. I normally do that anyway but there’s been times when it’s been nice.

Unless I had to by code install an unfused disconnect outside I would put overcurrent protection outside and just use a non service rated ATS inside.
Not really sure if PA. Is requiring emergency disconnect or just a way of shutting it off.

 

[hillbilly1]

What gets me with those service rated transferswitchs, they can’t really be an “Emergency disconnect”, because as soon as you turn it off, the generator starts, and repowers the house.

 

[Birken Vogt]

What gets me with those service rated transferswitchs, they can’t really be an “Emergency disconnect”, because as soon as you turn it off, the generator starts, and repowers the house.

Generator disconnects and/or prime mover shutdowns are usually required near the service entrance so that would mitigate that.

 

[hillbilly1]

Generator disconnects and/or prime mover shutdowns are usually required near the service entrance so that would mitigate that.

Required, but seldom done. I’m the only one in my area that does that. I was talking to a generator installer at the supply house, and he gave me a deer in the headlights look when I asked him if they were doing it.

 

[Birken Vogt]

The county has been enforcing it here for years now, since generators became popular.

 

[don_resqcapt19]

What gets me with those service rated transferswitchs, they can’t really be an “Emergency disconnect”, because as soon as you turn it off, the generator starts, and repowers the house.

Service rated transfer switches have a off position that disconnects the load from both the utility and the generator.

 

[Birken Vogt]

Service rated transfer switches have a off position that disconnects the load from both the utility and the generator.

Not the residential ones I usually see. The Kohler RXTxxxxSE and the Generac equivalent have nothing but a 200 amp breaker on the utility side. It is assumed you know how to turn off the generator if you want to work on the ATS.

 

[qcroanoke]

Service rated transfer switches have a off position that disconnects the load from both the utility and the generator.

Question.
Is a service rated ATS considered an emergency disconnect and how many people would know to turn off both sources?
I am not familiar with residential switches.

 

[don_resqcapt19]

Not the residential ones I usually see. The Kohler RXTxxxxSE and the Generac equivalent have nothing but a 200 amp breaker on the utility side. It is assumed you know how to turn off the generator if you want to work on the ATS.

Not sure...UL 1008, the listing standard for transfer switches says:

a transfer switch marked for service equipment use shall be provided with readily accessible externally operable means to disconnect all ungrounded supply conductors of both the normal and the alternate sources under any condition of the normal and alternate supplies. The disconnecting means shall be manually operable by using a mechanical operating handle or an electrically operated switch.

I see that as requiring a listed service rated to open both the normal and standby source

 

[hillbilly1]

Service rated transfer switches have an off position that disconnects the load from both the utility and the generator.

Not the ones I’ve installed.

 

[hillbilly1]

Not the residential ones I usually see. The Kohler RXTxxxxSE and the Generac equivalent have nothing but a 200 amp breaker on the utility side. It is assumed you know how to turn off the generator if you want to work on the ATS.

Same with the Cummins/Onan.

 

[hillbilly1]

Not the residential ones I usually see. The Kohler RXTxxxxSE and the Generac equivalent have nothing but a 200 amp breaker on the utility side. It is assumed you know how to turn off the generator if you want to work on the ATS.

You would think they would have a start or transfer inhibit aux contact on the breaker, but they don’t.

 

[Birken Vogt]

Not sure...UL 1008, the listing standard for transfer switches says:

I see that as requiring a listed service rated to open both the normal and standby source

Some old Kohler switches had the disco on the standby source but they quit doing that decades ago.

I don't know how they get away with it, I am just reporting what I see. All residential/light commercial service rated switches have only one breaker.