Hot Neutral

[mayfair]

Hi Guys
Have a 3 phase installation 3 phases plus the neutral are fed by 25mm cables into 63A circuit breaker then all split of into the 3 RCD's with 10mm cable inc the N lives are all warm but Neutral is hot checked screws for tightness etc no circuit is reading more than 41 Amps . Any ideas???????????
Cheers
Mayfair

 

[Guest123]

All the computers and all other loads need to be on when you current clamp the neutral conductor to give you a realistic reading.

You may find you will at least need to increase the size of the neutral conductor as a minimum.

 

[davelerave]

think so - oversize the neutral on 3-phase 4-wire if neccessary


the ordinary clamp wont measure harmonic currents although i think overcurrent protection (if used on a neutral) would operate


may not be that anyhow

 

[mayfair]

Hi guys
put a 25mm N out of mcd split to 3 16mm also up graded lives to 16mm seems to have it sorted ............ fingers crossed