Generator breaker down sizing.

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California
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Electrician
Hello All,
I'm installing a Generac 26kw model 7291 on a residence that will be powered from NATURAL GAS. This unit comes with a 110a main breaker. According to the specs on this generator its rated maximum continuous power capacity under natural gas is 22,500 watts (93.8amps), apparently its only rated at 26kw when it runs of propane (which im not). My question is... I would like to change/derate the main breaker to 100a on the generator so i can be able to pull #3 UL Type TC-ER-JP 600V generator cable instead of #2 UL Type TC-ER-JP 600V generator cable. If i change the main breaker on the generator, does that violate any warranty or UL listings? OR there's an exception under 445.13 (A) basically stating the following: Exception: Where the design and operation of the generator prevent overloading, the ampacity of the conductors shall not be less than 100 percent of the nameplate current rating of the generator. So do i need 100amp wire or at least 110 amp wire even though the generator will not provide that output.

Basically I'm trying to keep costs down. The cable I'm referring to is a Generac brand cable equipped with all the control wires necessary for the generator.
 
The second part, 110%, does not apply,

As to question #1, it is a gray area. It is not going to void any warranty except on the parts installed by you. As to UL, technically it could be yes, but what is the hazard? Unless you install the wrong type of breaker.
 
Can the install qualify under 240.21(b)(5) {outside & terminate in a 100 amp breaker) ??
Ifs so, apply that tap rule and leave the 110 breaker.
 
Can the install qualify under 240.21(b)(5) {outside & terminate in a 100 amp breaker) ??
Ifs so, apply that tap rule and leave the 110 breaker.
Hello Augie47, Unfortunately the cable will be running through the attic roughly 70' before it terminates into its overcurrent protection.
 
The second part, 110%, does not apply,

As to question #1, it is a gray area. It is not going to void any warranty except on the parts installed by you. As to UL, technically it could be yes, but what is the hazard? Unless you install the wrong type of breaker.
Thank you for your input.
 
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