Using page 7 and onward as a reference, are the short circuit calculations shown accurate enough for breaker AIC sizing purposes? If so, how much do they deviate from symmetrical components and X and R calculations? Will they ever produce values below a "real" short circuit calculation?

What about 3 phase grounded wye?

Also why don't molded case breakers list the X/R ratio they base their fault current on? Is there ever a time when the X/R ratio of a 600 volt and under scenario will exceed that of the breaker?

For the sake of the discussion lets assume the POCO transformer primary is an infinite source.

https://www.scribd.com/document/3520...it-Calculation

What about 3 phase grounded wye?

Also why don't molded case breakers list the X/R ratio they base their fault current on? Is there ever a time when the X/R ratio of a 600 volt and under scenario will exceed that of the breaker?

For the sake of the discussion lets assume the POCO transformer primary is an infinite source.

https://www.scribd.com/document/3520...it-Calculation

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