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Phase rotation

geov
Hi all, long time not here, but as always, value the opinions of members.

EICR on a commercial. Incoming phase rotation correct at head, but all 8 sub mains in the MCCB panel have been incorrectly installed L3, L2, L1.

Been like this since the building was refurbished 10 years ago.

They do have some three phase equipment which is running happily ( tho’ I’ve not been able to switch off to see if the rotation fail  has been corrected at the local isolator).

I’m minded to code C3 - anyone disagree & if so why?
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    gkenyon:

    Whilst verification is required in 643.9, a requirement for verification cannot in itself be transposed into a requirement for design and erection. Basically, you complied with the requirement to verify it (and came up with the answer that the phase rotation is not maintained).


    Surely that is a matter of contract.


    If both ends of the distribution circuits are wired back-to-front, it hardly matters because the phase sequence will be correct at the next level of DB. Even if one end is right and the other is wrong, the sequence at, for example, sockets should have been verified and corrected if necessary.


    I think that C3 is appropriate in this instance, but I would have to consider C2 if a socket were reversed.


    The other point of non-compliance is identification of the conductors - 514.3 etc.


     


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  • 0
    gkenyon:

    Whilst verification is required in 643.9, a requirement for verification cannot in itself be transposed into a requirement for design and erection. Basically, you complied with the requirement to verify it (and came up with the answer that the phase rotation is not maintained).


    Surely that is a matter of contract.


    If both ends of the distribution circuits are wired back-to-front, it hardly matters because the phase sequence will be correct at the next level of DB. Even if one end is right and the other is wrong, the sequence at, for example, sockets should have been verified and corrected if necessary.


    I think that C3 is appropriate in this instance, but I would have to consider C2 if a socket were reversed.


    The other point of non-compliance is identification of the conductors - 514.3 etc.


     


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