On 27/09/2019 20:56, ARW wrote:
On 27/09/2019 09:54, wrote:
Three phase DB. Turned up and tried to turn the lights on, to find
that all the MCBs controlling circuits with lights (and some without),
plus a submain that also had a lights circuit running from the
secondary DB, we're off.

The only possibly explanation I can think of is that someone had
turned them all off, because they were blindly trying to turn off the
lights after working there and hadn't noticed the timer override
master switch.Â* Problem with that theory is that in order to turn the
lights on in the first place they would have had to know about the
override switch!

Is there any possible electrical fault which could trip half a dozen
circuits and leave no signs, a maximum of 24 hours since the lights
were circuits were last on. There was no evidence of water leakage.



There is only one explanation.

Some pillock has turned the MCBs off.



Turn them on, and put some superglue on the MCB tabs then
you will catch the culprit next time :-)