In article ,
Jason Arthurs writes:
I've lived in this house for two years now and as soon as summer
arrives so do the periodic electrical dropouts, which is a shame
because the batteries in my UPS have just decided they're knackered.
generally very poor reliability. Our domestic voltage varies between
240-250v, but usually hovers around 248v (as the over voltage alarm on
my UPS often complains).

Our local provider is Midlands Electricity Board (npower?), is there
any point in complaining or will they simply tell me that everything
is within tolerance? Didn't EU harmonization mean our voltage was
supposed to be a maximum of 243.8v (i.e. 230v +6%)?

Max voltage is 230+10%=253V.

It might be worth complaining about the brownouts and cuts.
I was working for a small software company some years ago in
a small village, and we used to get power cuts like this, in
our case more often when it started raining. I supplied the
log from our UPS with all the evidence in it. It turned out
the power company didn't know anything about the problem (it
had been going on as long as anyone could remember). They
found a fault on the 11kV feeder, and the problem almost
completely went away. Still got the odd one when a squirrel
hopped across the 11kV lines, and one quite spectacular one
when a digger outside went through an 11kV underground cable
just after the driver had been told exactly where it was.
(Could have been worse -- the other thing he could have hit
was a high pressure sewage pipe from the sewage pumping
station which pumped several villages' sewage up hill to the
sewage works 5 miles away;-).

--
Andrew Gabriel