Ze / PFC conundrum at factory

[Dunc88]

If I've understood correctly... it's a new supply to DB4 but no changes in DB4. If so, perhaps an update to the DB4 details showing the new Zdb ?

Yeah i'll go with that so you can see all consumer units are on certificates for the sake of the install, wont hurt for future reference either. I suppose in even bigger installations where there are multiple DB's not associated with one you are installing a new circuit in, it's acceptable not to include these in your installation cert providing the one worked on has certs right back to the origin?

 

[Dunc88]

No way I would "piggy back" one board from another.

I've asked a couple of people about this as it didnt look right to me & i'd never seen it before & they seemed to think it was perfectly acceptable. Seems a very lazy/odd way to do it as DB3 & 4 arent too far away from each other & DB3 has plenty of space in it! Frustrating coming across things like this that you havent had anything to do with but thats how it goes sometimes (/most the time!!)

 

[Risteard]

A type 2 bs 1361 for example has a typical ka rating of 33ka so I think it will.
Like I've said manufacturers should be consulted if back up protection is used

The 33kA is for the fuse - not what the distribution board assembly is conditionally rated to owing to Annex Zb (previously Annex Za).

 

[Ian1981]

The 33kA is for the fuse - not what the distribution board assembly is conditionally rated to owing to Annex Zb (previously Annex Za).

We are not talking about domestic installations
Were it's highly unlikely to see such fault currents