Site cabin EICR

There is a hidden assumption there that smaller gensets are not likely to be supplying more than one load, or at least no more than one burger van or caravan or whatever, and that the whole thing can be seen as a self contained equipotential zone. Larger gensets tend to sit at the centre of a web of outbound cables, and you do not want a fault on one load to make something on the far side of site suddenly dangerous.

I must admit I see the 20 ohms in '7430 as being intended for the case of larger fixed private gensets, usually 3 phase, more like fixed 'plant' than tow along, and the more ' can you trip the RCD?'  based advice of BS7909 a better fit for portable units.

Actually most gensets and inverters below about 3kVA do not  bond the N-E either so the RCD  also becomes pointless, and it has more in common with an isolated supply like a shaver socket.

There is a hidden assumption there that smaller gensets are not likely to be supplying more than one load, or at least no more than one burger van or caravan or whatever, and that the whole thing can be seen as a self contained equipotential zone. Larger gensets tend to sit at the centre of a web of outbound cables, and you do not want a fault on one load to make something on the far side of site suddenly dangerous.

I must admit I see the 20 ohms in '7430 as being intended for the case of larger fixed private gensets, usually 3 phase, more like fixed 'plant' than tow along, and the more ' can you trip the RCD?'  based advice of BS7909 a better fit for portable units.

Actually most gensets and inverters below about 3kVA do not  bond the N-E either so the RCD  also becomes pointless, and it has more in common with an isolated supply like a shaver socket.