I am a firm believer in two series R.C.D.s in installations. If one fails or is a bit sticky the other should operate and clear a fault. I have personally found several R.C.D.s that were faulty in installations. Relying on just one R.C.D. is taking a bit of a gamble.
You would probably be better off focusing on the bonding and then design for an increased effective CPC size - that way you have a combination of both passive and active safety. RCD's in series are effective from some faults, but not all faults - if you are thinking along these lines then it's important to ascertain the common mode failures
That said, twice the expenditure on RCD's to save a very small number of people hardly seems worth it - from a safety perspective
I am a firm believer in two series R.C.D.s in installations. If one fails or is a bit sticky the other should operate and clear a fault. I have personally found several R.C.D.s that were faulty in installations. Relying on just one R.C.D. is taking a bit of a gamble.
You would probably be better off focusing on the bonding and then design for an increased effective CPC size - that way you have a combination of both passive and active safety. RCD's in series are effective from some faults, but not all faults - if you are thinking along these lines then it's important to ascertain the common mode failures
That said, twice the expenditure on RCD's to save a very small number of people hardly seems worth it - from a safety perspective
