I think with all that in mind, an upfront outboard RCD in a metal box is by far the worst way to go on a TT earthing system.
Agree, with a note that a switch in a metal box feeding a selection of non RCS protected bus bar or split tails to many RCDs is much worse than an RCD in a smaller metal box with only tails in and out and nothing else.
It would be safer with an un-earthed metal box, and some more insulation inside.
The safest solution by far is an RCD on its own in a plastic box, tails in and out and no electrode only CPC anywhere near it.
The regs in their current form can be read in a way that seems to recommend some highly suspect practice.
I think with all that in mind, an upfront outboard RCD in a metal box is by far the worst way to go on a TT earthing system.
Agree, with a note that a switch in a metal box feeding a selection of non RCS protected bus bar or split tails to many RCDs is much worse than an RCD in a smaller metal box with only tails in and out and nothing else.
It would be safer with an un-earthed metal box, and some more insulation inside.
The safest solution by far is an RCD on its own in a plastic box, tails in and out and no electrode only CPC anywhere near it.
The regs in their current form can be read in a way that seems to recommend some highly suspect practice.
