Good afternoon
A quick and maybe somewhat silly question regarding the table 41.3 of BS7671 where it gives the max zs permitted for MCBs
We can see that the fuses have separate tables for 0.4s and 5s disconnection time max Zs
However MCBs have one table only that gives the maz Zs for both 0.4s and 5s
Why dont MCBs have one table with max zs for 0.4s disconnection and one table with max Zs for 5s disconnection?
So for exampe a C32 has max zs 0.68Ω
How can this be both for 0.4s and for 5s disconnection time?