Standard Sizes for MV or HV Circuit Breakers

[recs]

The NEC allows for transformer protection to go to the next standard size. It is very clear how to apply this rule for low voltage circuit breakers. But what are defined the medium voltage or high voltage breaker standard sizes?

 

[Zogzog]

Depends on where you are in the world and what standards the breakers are designed to.

 

[LionelHutz]

I don't believe there are no are any fixed standards. Sizes like 800A, 1200A, 1600A, 2000A or 3000A are fairly common medium voltage breaker frame sizes. However, the trip currents and times are typically all adjustable so you don't have to round up to the next available size.

 

[jghrist]

The protection level of MV and HV breakers is dependent on the relay setting, not on the breaker rating.