You may check some standards for the fault withstand of switch gears. for instance, in some areas, the breakers are designed to withstand 40kA for 3s and 100kA for 1s and be tested for this(I can not recall the exact numbers). so if the breaker is designed to withstand only 1s, why the cable...
I believe in NEMA MG1
32.1 BASIS OF RATING
"Synchronous generators shall be rated on a continuous duty basis, and the rating shall be expressed in
kilovoltamperes available at the terminals at 0.8-power-factor lagging (overexcited)."
And
"33.2 RATINGS
33.2.1 Power Factor
The preferred...
if you don't know the load details,use 0.8 lagging power factor as in NEMA standard. and I believe all the manufactures will make the genset with 0.8 PF as required by NEMA no matter what cost.
Almost all transformers have the ability to change voltage ratio through the tap changer online or offline. So if it is 2% drop on the prime side, you can change tap to make up this 2%(normally 2.5% per step on the tap) and keep secondary voltage unchanged.
