nothing like being thrown a curve ball

[martin mcguinness]

I was asked to change a light fitting in a neighbours house easy job help out a neighbour I thought. I had my 2nd oldest son with me so thought it would be good to show him how to work safely ie how to use a voltage indicator and work safe.
normal procedure
prove indicator using proving unit
check voltage at light fitting
demonstrate fitting dead (lock mcb off)
prove indicator with proving unit
get young lad to disconnect light and he said I've just had a shock from wiring (single twin and earth at light ) I thought I just checked and its dead so I checked it again and no voltage so I decided to do it. I got a cracker of a shock made me look like a total plank in front of young lad so I checked again, no voltage between L+N but 240 between L+E.
turns out when there smart meter fitted the installer made a small mistake (don't know how to find sarcastic emoji)
turns out the MCB switched the neutral as L+N reversed
anyone else had something like this
and DNO contacted to rectify issue

 

[johnduffell]

Not much use if the cut out is reverse polarity though?

how many cutouts are reverse polarity though?
the DNO have trained jointer teams doing all work after install, the meter fitters not so much. Having seen a jointer team working there wasn't much chance to make an error.

 

[stevels4]

how many cutouts are reverse polarity though?
the DNO have trained jointer teams doing all work after install, the meter fitters not so much. Having seen a jointer team working there wasn't much chance to make an error.

Very true when using concentric cable but I’ve seen 2 reversed when fed from over heads as the cables are generally the same colour and if the cutout is mounted upside down to accommodate the cables entering from above confusion does arise with the cut out fuse now on the right.

 

[Squid]

Not much use if the cut out is reverse polarity though?

I think there would nave been other issues that would have been noticed like the electricity company paying you as the meter was running backwards............

 

[Which One’s Live?]

DNO reverse polarity is as rare as hen’s teeth.

Metering side: more likely. Obviously, you’d still be isolating everything if you did happen to pull the fuse. Admittedly, it’s usually the customer tails that are reversed than the cutout side.