Yes I have done Mean, Median and Mode. And LED bulb design does vary manufacturer to manufacturer, unfortunately price seems to have very little impact on quality, I have shown this
of G9 bulbs many times, the larger one was also cheapest, and did not comply with UK regulations, but worked far better to smaller one, but the big change is I use to buy a pack of bulbs for a pound or two, now one bulb can cost £5 or more, and where one has a chandelier or silly down lights one room may have upwards of 8 bulbs.
In the old days of tungsten I kept a draw or cupboard full of bulbs and swapped as required, I would say an average of a bulb every other week, but had less bulbs, now an average of a bulb a year. Even the rarely used bulbs which are still tungsten seem to last longer.
Then I walk into my old house now my sons, and see 10 failed bulbs, he blames cheap toolstation bulbs, but I don't use expensive bulbs, in fact the one time I bought expensive Philips CFL golf ball 8 watt bulbs their life was very short, and 16 of them so not one odd poor one.
Seems more likely simply unlucky and a bad batch. But same house where a batch of Philips bulbs failed to a batch of toolstation bulbs failed, with no SPD, and same house where the RCD would trip in a thunder storm, no over head cables in the street, but clearly thunder storms do affect the supply.
Not convinced a SPD will help, but also not convinced a SPD will not help. I have fusebox consumer unit, when I bought it a few years ago the SPD was two module wide with no overload, today one module wide with overload
what is going on?
Nominal Discharge Current (In 8/20us) 20kA
Maximum Discharge Current (Imax 8/20us)40kA
Both types.
The video linked in previous post does talk about this, and also the types of SPD, both say T2 as said at around £30, BG and Fusebox, I fitted one, seemed worth the money to save LED's even if not sure they work. But for Wylex nearly £90 and one has to ask what is the difference?
IET said:
In the previous edition of the IET Wiring Regulations, BS 7671:2008+A3:2015, there was an exception for some domestic dwellings to be excluded from surge protection requirements, for example, if supplied with an underground cable, but this has now been removed and it is now a requirement for all types of premises including single dwelling units. This applies to all new build and properties being rewired.
I note
this IET resource shows a Wylex CU with double width SPD and no MCB. different make, but looks like my own CU.