Standby generator wire sizing

[Hfalz1]

I am hooking up 22kW to 26kW standby generators and I am being told that a whole wire generac cable is good for 24kW and below. The cable contains 3-#3 cu and 1-#8 cu conductor. Also it has 6- #18 cu wires for the controls. The generator has a 100A breaker and the ATS is 200A. Is this correct? It seems to me the wire would have to be larger for the feeds.

 

[charlie b]

What voltage?

 

[roger]

#3 is good for 100amps. Please update your profile to include your trade.

 

[Hfalz1]

240V. Whole home generac natural gas generator. Electrical. Single phase.

 

[Hfalz1]

#3 is good for 100amps. Please update your profile to include your trade.

How do i update profile sir?

 

[jaggedben]

240V. Whole home generac natural gas generator. Electrical. Single phase.

100A @ 240V is 24kW.

 

[roger]

How do i update profile sir?

Click on your name and it will open a window where you can edit your info

 

[Hfalz1]

#3 is good for 100amps. Please update your profile to include your trade.

no derating?

 

[roger]

So have you figured out how to fix your profile?

 

[gulf0927]

This thread talks about it in detail.

24kw Generac generator 200 amp Ats

Good day, Customer just ordered a 24kw Generac generator and this will be my first install. They have a 200 amp service. The generator has a 100 amp main breaker but the ATS is 200 amps. I’m trying to order my wire but am a bit confused on sizing. House service fed underground with 4/0...

forums.mikeholt.com

 

[gulf0927]

"Whole home" is a sales point of emphasis. In reality we size them according to load calculations. The ATS has a 100 amp breaker and usually load shedding ability built in to protect the generator and wire.

 

[LarryFine]

For 100a generator feeders, I like using #2 al SER.

 

[Hfalz1]

So have you figured out how to fix your profile?

no sir

 

[Hfalz1]

no sir

it just brings me to put a picture.

 

[LarryFine]

it just brings me to put a picture.

Click on your name on the upper right, then click on account details.

Fill in the info you want in the various spaces, then click on save.

You can always make changes if you don't like how it appears.

 

[roger]

If Larry's instructions don't work I can do it for you.
Let me know what it should be

 

[Hfalz1]

If Larry's instructions don't work I can do it for you.
Let me know what it should be

I got it sir. Thank you.

 

[frofro19]

For 100a generator feeders, I like using #2 al SER.

I used to use #2 AL but for a little more money, the #3 copper and #8 ground pull a Lot better in the conduit.

 

[MattG0311]

For 100a generator feeders, I like using #2 al SER.

Are you using 310.12 to size this feeder as it supplies the entirety of the home?

I ask because table 310.16 gives #2 AL an ampacity of 90amps.

I never thought of using 310.12 in a generator scenario and am curious if this is compliant.

 

[LarryFine]

Are you using 310.12 to size this feeder as it supplies the entirety of the home?

Yes, I am.

I ask because table 310.16 gives #2 AL an ampacity of 90amps.

Yes, it does.

I never thought of using 310.12 in a generator scenario and am curious if this is compliant.

I hope so.