Age of supply

[JohnW2]

....There, it cuts the supply to most of my tails from the meter.

Most?

Rather oddly, the last two smart meter installers have taken it upon themselves to apply a seal to >my< isolator.

I have a slightly more complicated variation on that theme. There is an 'official' seal on the supply side of my isolator, and a plastic one on the load side. I would guess that the latter is to discourage 'casual DIY interference', whilst the former (although not necessary for 'anti-fraud' reasons, since it's downstream of the meter) is perhaps an attempt top underline the fact that interfering with the incoming tails (without pulling the service fuse) would be definitely dangerous?

Kind Regards, John

 

[Harry Bloomfield]

Most?

Most of the length of the tails.

My isolator only has provision for a single seal, on the cover screws. It must be standard practice for them to seal them then..

 

[JohnW2]

My isolator only has provision for a single seal, on the cover screws. It must be standard practice for them to seal them then..

Doesn't your isolator have separate covers for incoming and outgoing cables? What make is it?

Kind Regards, John

 

[winston1]

Humm I think its actually a requirement to have one if you have 2 cus.
To have 1 isolation point.

Source?

 

[JohnW2]

Source?

How about ...

462.1.201 A main linked switch or linked circuit-breaker shall be provided as near as practicable to the origin of every installation as a means of switching the supply on load and as a means of isolation.

?

Kind Regards, John

 

[Harry Bloomfield]

Doesn't your isolator have separate covers for incoming and outgoing cables? What make is it?

Kind Regards, John

I'll get back to you on that..

 

[flameport]

One building can have more than one installation, each with it's own isolator.

 

[Harry Bloomfield]

How about ...
?

Kind Regards, John

I didn't know that, but I didn't install the second CU, it was installed because my primary CU was fully occupied and and extra two circuits were needed for a stair lift and a linked fire alarm system. The second CU supply I assume was tapped off the primary tails by the installer - I must take a look to see what he did.

 

[AndyPRK]

The isolators have twin covers but Wyler for example only supply one screw that has a hole in it( for a wire. )

If the 2 cu’s are next to each other it’s nit a big deal.
However I think fire crews like one switch to cut everything off

 

[JohnW2]

One building can have more than one installation, each with it's own isolator.

Yes, we've discussed that before, and the BS7671 definition of "Installation" is so vague as to be totally unhelpful as a referee (since it could be interpreted as meaning that any final circuit could be regarded as 'an installation'!).

That being the case, I think one can but apply common sense in relation to what one regards as being 'the spirit' of "an electrical installation".

Opinions will obviously vary, but I would personally say that two or more DBs/CUs side-by-side (or in close proximity), fed from a common metered supply and with final circuits fairly 'randomly' spread across the CUs all constituted a single "Installation".

On the other hand, if the DBs/CUs are essentially serving different parts of the building (and particularly if they are also relatively distant from one another) then I think there is a case for arguing that they represent different 'Installations', even if they have a common metered supply. Indeed, before I had a 3P+N isolator installed, I suppose I was, in my house, relying on that argument to satisfy the reg I mentioned above - since I essentially have one phase feeding (separately) DBs in each of three floors, with (then) separate isolators for each phase.

Having given my view, I don't doubt that there probably a good few people who will say something like "1 meter equals one Installation", or even "One service head/cutout equals one Installation".

What is your view?

Kind Regards, John

 

[333rocky333]

I have a pair of similar fuse boxes in my house, both 4 fuse versions

Is that an MEM board with a Wylex mcb bodged in at the end

 

[Harry Bloomfield]

I'll get back to you on that..

It is a Wylex AC22A 100amp with enclosure. The upper section of the cover, the consumer side, is removable separately from the live incomer end.

 

[JohnW2]

It is a Wylex AC22A 100amp with enclosure. The upper section of the cover, the consumer side, is removable separately from the live incomer end.

Thanks. As I implied, that is the situation I've always seen.

.. so, have both parts of the cover been sealed?

Kind Regards, John

 

[Harry Bloomfield]

Thanks. As I implied, that is the situation I've always seen.

.. so, have both parts of the cover been sealed?

Kind Regards, John

No, just the incomer side. My thought was why are they sealing my own property from interference, what next - sealing my CU against being interfered with?

 

[JohnW2]

No, just the incomer side. My thought was why are they sealing my own property from interference, what next - sealing my CU against being interfered with?

That's similar to mine, then, albeit I also have the token plastic seal on the consumer side.

As I said, given that (unlike the situation with cutout and meter incomer) there is no 'anti-fraud' reason to seal the incomer into the isolator, I can but assume that they are just being 'public spirited' by deterring people from exposing the incoming feed to the isolator (which will always be live unless the cutout fuse is pulled).

Kind Regards, John