Landlords EICR and t&e sub mains without RCD

[Mapj1]

For TT surely there must be some kind of RCD up front, as changing to SWA would be worse than useless - a nail connecting to a live wire and to a high Z earth that just makes the building live but trips nothing is worse than a nail on its own that is just live.
If you can beef up the thin bit of wall to 50mm, or maybe make the route un-hidden in some way (metal detector and some labels/paint ? ) then a 100mA or 300mA up front would be my preferred But a long run of any cable on TT without an upfront RCD is asking for trouble, even a few m of meter tail in plastic trunking feels icky.

 

[Bobster]

For TT surely there must be some kind of RCD up front, as changing to SWA would be worse than useless - a nail connecting to a live wire and to a high Z earth that just makes the building live but trips nothing is worse than a nail on its own that is just live.
If you can beef up the thin bit of wall to 50mm, or maybe make the route un-hidden in some way (metal detector and some labels/paint ? ) then a 100mA or 300mA up front would be my preferred But a long run of any cable on TT without an upfront RCD is asking for trouble, even a few m of meter tail in plastic trunking feels icky.

An upfront RCD is not a must, although in most TT situations tt is highly likely. Especially in domestic situations where it is not only needed for fault protection due to low Zs.

I've done a few installations where the Ra is sufficient not to require them.