Can 3 individual mcbs(instead of a 3 or 4 pole mcb) be used for circuit protection of a 3 phase distribution circuit, where a 4 or 5 core swa is used? Is there a requirement that all phases must be disconnected in the event of a fault?
Can 3 individual mcbs(instead of a 3 or 4 pole mcb) be used for circuit protection of a 3 phase distribution circuit, where a 4 or 5 core swa is used? Is there a requirement that all phases must be disconnected in the event of a fault?
well if was 3 fuses they may not all go at once, and that is common arrangement. It rather depends on what is at the other end and if the load will care. Some types of rotating machinery do not appreciate 'single phasing' and need a dropout configured so that if one phase drops the thing is cut off, but that is normally in the control gear
Mike.
There will be no 3 phase loads.
then you have no problems
That sounds like 3 SP circuits with a shared neutral even if they are all in the same cable. See the definition in Part 2 on page 31. The danger is that if one (or two) of the MCBs is opened, the neutral may still be carrying a current.
That sounds like 3 SP circuits with a shared neutral even if they are all in the same cable. See the definition in Part 2 on page 31. The danger is that if one (or two) of the MCBs is opened, the neutral may still be carrying a current.
We're about to take you to the IET registration website. Don't worry though, you'll be sent straight back to the community after completing the registration.
Continue to the IET registration site