I have posted a piece here which is also on the TT topic, but is more general and I think a new thread would be better. Your voice is heard. See below.
My reading of that Mike, is that the RDCs require a protective device of B or C type MCB (Not a D) of not more than 50A, again emphasising that the RCD maximum current is not more than 63A (I assume they are 63A RCDs) at all. The fact that the leaflet was printed / written in 2012, is interesting and is probably not the current position, which is very poor. You now have to meet the BEAMA sheet which I would inspect your new installation against for compliance, and if you don't fit these MCBs you get an unsatisfactory C2! In fact as you are fitting RCBOs there is no problem (at the moment), but if that were a filled unit of older stock it may already fail their own paper unless you have a 60A main fuse.
In my view this is not either the position or intention of BS7671 itself, and it is the MI (or perhaps even the product) which is at fault.
On another note my playing with RCDs is still proving interesting, and I am not at all convinced that an RCD with a high fixed load still trips at 30mA or whatever, particularly if the waveform is not ideal. Perhaps there is more to this than meets the eye.
My reading of that Mike, is that the RDCs require a protective device of B or C type MCB (Not a D) of not more than 50A, again emphasising that the RCD maximum current is not more than 63A (I assume they are 63A RCDs) at all. The fact that the leaflet was printed / written in 2012, is interesting and is probably not the current position, which is very poor. You now have to meet the BEAMA sheet which I would inspect your new installation against for compliance, and if you don't fit these MCBs you get an unsatisfactory C2! In fact as you are fitting RCBOs there is no problem (at the moment), but if that were a filled unit of older stock it may already fail their own paper unless you have a 60A main fuse.
In my view this is not either the position or intention of BS7671 itself, and it is the MI (or perhaps even the product) which is at fault.
On another note my playing with RCDs is still proving interesting, and I am not at all convinced that an RCD with a high fixed load still trips at 30mA or whatever, particularly if the waveform is not ideal. Perhaps there is more to this than meets the eye.
