Solution to high cost AFDDs?

[Selfmade]

Hi Folks

Screwfix have Wylex combined AFDD/RCBOs for over £200 each. For a simple hypothetical installation with 2 lighting and two ring final sockets circuits, that's over £800 for devices alone.

So, if one were to install two consumer unit enclosures, one with main switch and two 40A AFDD/RCBOs, each feeding one 32A MCB for a sockets circuit and one 6A MCB for a lighting circuit, in the other enclosure, arranged so that sockets and lights in each room are on different AFDDs, one would in effect have a dual AFDD/RCD consumer unit, something that doesn't (yet?) seem to be available to buy.

Can anyone see any problems with this?

 

[Selfmade]

Wow! What a popular topic! Forgot to say, Happy New Year All!

 

[Selfmade]

When you get an "arc fault" how you going to find it?
Its going to be like finding an rcd/leakage fault with no test gear.

My solution is don't fit them until the manufacturers come up with a much cheaper alternative preferably that take up just one space in the consumers unit.

Insulation resistance might show a parallel arc, maybe higher than expected resistance for a series arc (maybe a bit of guesswork with the second)? Or try switching off one MCB at a time and resetting the AFDD (maybe not much use for an intermittent fault)? Your solution may well be more practical!

 

[Selfmade]

18th edition 1st amendment:
Items that may cause false triggering that can be fitted with a snubber device along with a risk assessment.

Like every single light switch

 

[Selfmade]

Perhaps the new 18th MFT they keep advertising will have this function!! I don't think

Something to help us press the test button and tick a box on the form.

 

[Generator]

There's a more sinister aspect of this AFDD business - they're not mandatory BUT, if a homeowner declines a 'recommendation', what would be an insurance company's response to a future claim following a fire?

 

[Silly Sausage]

There's a more sinister aspect of this AFDD business - they're not mandatory BUT, if a homeowner declines a 'recommendation', what would be an insurance company's response to a future claim following a fire?

If my insurance company wants to give me a £2000 discount if I get an AFDD kitted out board, I'll have one fitted!

 

[Toneyz]

It seems we are protecting against poor workmanship AFDD loose connection etc and metal consumer units RCD protection if someone nails a picture up above a socket long gone the days of protection by a piece of fuse wire.

 

[Great68]

Back to the Op, AFDD's wont work on ring circuits anyhow.

 

[Nebu1a]

If the IET do make a push on AFDDs then I expect they will eventually phase out ring finals

 

[Selfmade]

Back to the Op, AFDD's wont work on ring circuits anyhow.

Seriously? And yet they are not exempted? So we are expected to recommend to customers a device costing over £200 in situations where it will achieve nothing?

 

[Disgrunteled landlord]

This is ridiculous legislation. £1500 for a six way distribution board to protect against a loose screw is barmy. More money for Chinese manufactures that will probably fail inside a couple of years

 

[davesparks]

This is ridiculous legislation. £1500 for a six way distribution board to protect against a loose screw is barmy. More money for Chinese manufactures that will probably fail inside a couple of years

What legislation are you referring to?

And what is protecting against a loose screw?

 

[Electro-tech]

Maybe there is new legislation since 2019 that I have not heard of.