views please electricians

[ruds]

had a 3 phase meter changed at a block of flats i maintain after the guy had finished 2 of the mcbs would not reset he then removed fuseboard cover and said to maintenance guy that there was a loose neutral in fuseboard.after he had left site it was noted that across 2 phases the electronic equipment in 7 emergency light fittings a door entry system and an aov smoke system did not function

could this be down to a loose neutral in board
what else do you think could have caused all electronic components to cease working.

 

[Adam_151]

At a guess, hes moved the tails around a bit to allow the new meter to be fitted, and the strands of the cable have shifted about and allowed the conductors to become loose in the DB, and the neutral has actually slipped right out. Hes powered back up without checking the terminations on the other end of the tails hes been dragging around and in this case there has been no neutral present (because its fallen out) which has lead to the neutral point floating voltage wise, and due to an unballanced load two of the phases have received over voltage which has damaged equipment

It was reported in one of the trade mags that some place did some research into loose terminations of tails caused by meter fitters and came to the conclusion that in installations where the termination in the con/unit or db might be affected by the meter installation, then the meter op really ought to be checking the terminations afterwards (common sense really). Not sure what the current procedure the meter op.s are adopting at present. I suspect it hasn't filtered through yet.

I think, in you position, I'd be holding the metering company responsible for the damage though!