2357-604 task a

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Hi guys and girls, 4th year apprentice here on my last assignment of design.

struggling with a question just looking to pick some brains on how to find the answer dont want the answer want to be able to understand.

the proposed design for this installation includes the following protective devices:

bs en 60898 type d circuit breaker for mig welder ( which will be a 32a after my earlier calculation)

an mccb rated at 125a for the distribution circuit to the db2.

determine using manufactures info wether selectivity will be achieved.....

using the regs booked ive found that a 32a type d trip times 0.4s is 640a and 5s is 320a

but i cant find any info on a  125a mccb even on hager or schneider manufactures data?

any guidance would help 

thanks in advance

 

[Sharpend]

What other factors are taken into account when we refer to mfrs info for selectivity? 

Have you been given any other details of the install?