Series breakers aic fault clearing

[Cartoon1]

This area always confused me. The area that confuses me is typically the 3rd breaker. Example below:

A: Meter Center with 1600A main service breaker rated 65KAIC
B: Meters connected with each having 225A breaker rated 22KAIC
C: Panel being fed from the meter breaker rated 225A MLO, with 10KAIC branch breakers feeding a unit about lets says 50feet away.

Question 1: Lets assume 1600A main breaker 'A' is series rated with 225A meter breaker 'B'. Does branch breakers 'C' need to the be also series rated or is that a moot point, since the 10KAIC breaker could technically be anything (assuming there was lower than 5kaic? The 'A' and 'B' will clear out any fault before it gets to 'C'?

Question 2: Typically if it is the same manufacturer, for example square 'D'. They have the EZ meter centers, and homeline panels MLO that you connect to in tenants condos type building. Do they all automatically get series rated? The 'A' 'B' and the branch breakers 'C'?

Thank you

 

[don_resqcapt19]

If the available fault current at the breakers in the panels exceeds 10kA, then they either need to be series rated or rated for the available fault current at that point on the circuit.

 

[jim dungar]

The 'A' and 'B' will clear out any fault before it gets to 'C'?

That is never a given. Series ratings are not about which device clears the fault or how long it takes.

You need to consider how much fault current is at each of the breakers.
If you are starting with something more than 22kA at your meter you probably have less at your downstream panel.

But most series ratings are for two breakers, however some manufacturers have ratings for three breaker when multi metering is involved.
Series ratings are specific to each manufacturer.