With AFDD you are looking at something in the £1-2k region for a full CU at trade price, so it is something that is a very difficult to sell to most folk.I'v obviously lead a sheltered life, especially over the last four weeks, cost seem a bit prohibitive, but then if you take into account the three modules it replaces, perhaps not that expensive, thanks for that.
It is also a little unclear as to how effective they are in real terms, and so far no test equipment that I know of so for the 'AFDD' aspect you are trusting the self-test, though obviously you can verify the RCD action which provides some confidence on the electronics and mechanical trip reaction.
I suspect they will come down in price though but no idea how long for that to show.
[automerge]1587811846[/automerge]
I can't see a problem in getting 3mm clearance when open, but I can see a problem in having an arc-quench chamber in a single-module size device if you were interrupting a N-E fault at high current.I have come to the conclusion that you can't get true separation of 3mm on each pole without the extra width, which seems logical when you consider the doubling up of the number of mechanical components needed, obviously flying leads are not required.
Do you have a specific reason for needing this?