On 31/07/2018 10:21, Scott wrote:
Following on from the thread on the 18th edition wiring regulations,
does anyone have any comments on whether these devices are a good
idea, or if they are more intended for industrial premises with
machinery running unattended?

Is it one per supply or one per circuit?

One per circuit.

My assumption is that arcing would not trip an RCD/RCBO because there
is no leakage to earth and would not trip a 'fuse' because the current
may not exceed the rating (eg 32 amps). Is this broadly correct?

That's my understanding.

What I've yet to see is a cost/benefit analysis of requiring them for
domestic premises in (some or all) of the UK. And I won't hold my
breath. Despite being de facto tertiary legislation, changes to BS7671
don't have to bother with pettifogging little things like impact
assessments showing eg if we'll all need space for a CU twice the size
and four times the cost.

--
Robin
reply-to address is (intended to be) valid