Looking for code

[Pat1405]

New here and having trouble find a code. Customer wants to use 2 200amp breakers to feed a 400amp transfer switch. Any help would be great. I needbto show them that I can't use 2 breakers ( sources) to feed a single switch.

 

[Hv&Lv]

Wait..
(2) 200 amp breakers, in parallel, to feed a 400 amp transfer switch?

Thinking it will add up??
It won’t...

200 amps is all that’s going through.

 

[480sparky]

240.8.

 

[Pat1405]

Wait..
(2) 200 amp breakers, in parallel, to feed a 400 amp transfer switch?

Thinking it will add up??
It won’t...

200 amps is all that’s going through.

Yes it's a 400amp meter panel combo with (2)200 amp breakers feeding the 2 indoor panels

 

[Pat1405]

240.8.

Thank you sir

 

[texie]

New here and having trouble find a code. Customer wants to use 2 200amp breakers to feed a 400amp transfer switch. Any help would be great. I needbto show them that I can't use 2 breakers ( sources) to feed a single switch.

As mentioned, 240.8 prohibits this. And for good reason as it is dangerous thing to do on a number of levels. But I must admit he is not the first person to want to do this based on my experience.

 

[LarryFine]

You can feed two 200a breakers from a 400a T/S.

 

[brantmacga]

Yes it's a 400amp meter panel combo with (2)200 amp breakers feeding the 2 indoor panels

I have this same installation on a project coming up. I ordered two non-SER switches to install between each 200A MCB and load center. Generator will parallel the switches.

It’s also less than half the cost to do it this way. Non-SER switches are $550/ea, a 400A switch is $2300.


Sent from my iPhone using Tapatalk

 

[petersonra]

Yes it's a 400amp meter panel combo with (2)200 amp breakers feeding the 2 indoor panels

What you are describing is not two breakers in parallel. It is two feeders which is perfectly acceptable.

 

[Pat1405]

What you are describing is not two breakers in parallel. It is two feeders which is perfectly acceptable.

Only if the indoor panels have 200 amp main breaker correct?

 

[LarryFine]

Only if the indoor panels have 200 amp main breaker correct?

No. They're not in parallel unless both ends are tied together, which supplying two separate panels does not do.

 

[texie]

I'm not sure we are all on the same page here. I understand the OP to say he has a 400 amp meter /main that has 2 200 amp service breakers that he wants to feed a single 400 amp ATS from the 2 200 amp service breakers . AM I understanding this correctly? If so this obviously can't be done.