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Am I on the right lines, I ask?
I've just recently moved into this house which is nicely equipped with a large 15 circuit CU unit with a split load x2 RCD's but first, I think an EICR would be a good idea to give a starting point reference at least, before any work is done
I'm considering having a Lightning SPD (Cat1 + Cat2?)/MBO fitted with a visual status and replaceable capsule design- (as a definite addition)also an AFDD and it's this latter protection which has me pondering on the best way forward.

The price of the AFDD devices for each circuit with RCBO's seems to be likely to about £2k plus a day's (?) labour- so edging towards £2.5k for the whole plan to to be achieved

Q1- as these AFDD devices become more common and eventually mandatory in new builds/MHO's etc. I imagine the unit prices will fall but currently they seem to be around £120 each- alternatively since fires are not so common and this is not a high risk building (other than rats from the nearby stream nibbling through cables in the garden lights)- perhaps it would make more sense ftb to have a separate housing before the CU for 1 x AFDD/MBO (and the SPD) and maybe in a couple of years consider a full CU update- comments please?
Q2- Am I correct in thinking that whereas 1 x AFDD/MBO per circuit would immediately identify the faulty circuit but leave the rest of the power supply to elsewhere in the house live and still working- whereas one AFDD installed before the supply to the CU would knock out the whole power supply and necessitate an emergency investigation to get the property back on its feet quickly?

So far I haven't yet got any quotes in but my first impression is that few electricians have any depth, if any, experience of AFDD fitting and I would like to at least be able to ask sensible questions and understand what I am told

So thanks for reading this and more thanks, in advance, if you are able to advise me

Gordon
 
i would wait till the price drops ,but saying that the new amendment is coming out soon ,to be honest the manufactures will keep the price high ,if you can afford to put a second hand car in your meter cupboard good luck.
 
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Each year over two million fires erupt all over Europe. More than one third of these due to faults in the electrical installation which prevailingly occur as a result of dangerous arc faults. S-ARC1 and DS-ARC1 provide maximum safety in all buildings, thus protecting people and valuable assets. By early detecting arc faults and disconnecting the affected circuit they offer reliable and complete protection in any type of building. so do RCD and rcbo.
 
If you are thinking about this then the first thing to consider is getting an EICR done by someone competent and who is not using it as a "loss leader" to get more work. You might find someone on here who can do it or at least advise who to ask.

The RCD will catch the majority of arcs since most houses are wired in T&E so any fault tend to be live-earth, including rodent damage, etc. What you gain with AFDD is the ability to detect series arcs.

So far I have never seen an AFDD being used up-front for multiple circuits, I suspect that would only cause long-term grief due to the inability to narrow down what circuit is actually causing any occasional trips.

Adding SPD might be a good idea if you are in a rural location or fed from long overhead cables, again depending on how much lightning activity there is in your area.

Most CU that feature SPD tend to be the "type 2" sort for induced lightning (the 8us/20us waveform) from a nearby hit, but you can get "type 1 + 2" that can cope with direct hits on to the building or related metalwork (the 10us/350us waveform). They are significantly more expensive and larger as they have to absorb an order of magnitude greater energy, generally needed if your property has a lightning protection system (e.g. conductor & earth rod, etc) or is otherwise at high risk.

Generally an electrician would fit the CU manufacturer's own option if available, but you also get high quality 3rd party devices from the likes of Dehn, Kingsmill Industries, etc, who specialise in these types of product.
 
Having an EICR is a great idea, trying to keep up with current regs all the time is going to start being expensive.. The question you have to ask is how many electricians have SPD's in their own homes or AFDD's... I know I have a 17th edition split load board and have no plans to change it and I can as a trade get parts slightly cheaper and would not have any labour...

There are still thousands of places that still have the old wylex rewireable consumer units or worse and cabling that does not have a CPC in the lighting or Vulcanised rubber wiring..

First start by understanding what an SPD is for, if you have a very rural property with overhead power lines then yes an SPD would be a good idea, if you are the middle of a city then the likelyhood of a lightening strike between the transformer and your home is less likely, do you actually understand what an SPD is and what it does?
 
There are still thousands of places that still have the old wylex rewireable consumer units or worse and cabling that does not have a CPC in the lighting or Vulcanised rubber wiring..
Very good point, and to some extent my main concern with AFDD that you are not necessary spending money very wisely if there are other issues that present a higher risk of fire or shock and/or can be addressed cheaper than spending ~£2-3k on a new CU full of AFDD as the first option:
  • Old/poor cable condition
  • Lack of RCD protection
  • Incorrect overload protection (e.g. wrong fuse wire)
  • Dodgy appliances that ought to be recalled/scrapped
  • Hideous arrangements of extension leads due to a lack of planned sockets
  • No (or very basic) fire/smoke alarm provisions
  • Nothing in the way of fire blanket/extinguisher is high risk areas like kitchen/garage/workshop
  • Furniture that is high risk of fire and/or toxic fumes
  • Smoking (yes, it is a free and personal choice, but a poor one...)
Folks, open to discussion!
 
Having an EICR is a great idea, trying to keep up with current regs all the time is going to start being expensive.. The question you have to ask is how many electricians have SPD's in their own homes or AFDD's... I know I have a 17th edition split load board and have no plans to change it and I can as a trade get parts slightly cheaper and would not have any labour...

There are still thousands of places that still have the old wylex rewireable consumer units or worse and cabling that does not have a CPC in the lighting or Vulcanised rubber wiring..

First start by understanding what an SPD is for, if you have a very rural property with overhead power lines then yes an SPD would be a good idea, if you are the middle of a city then the likelyhood of a lightening strike between the transformer and your home is less likely, do you actually understand what an SPD is and what it does?
Since making my original enquiry I've been pondering on the chances of false trips on an AFDD installed between the incoming power and the CU, leaving the whole house without power and a difficult and time consuming search for a fault which doesn't actually exist - that would be horrible. On the other hand replacing the CU and installing AFDD's to each circuit would be an eye watering cost and until that were to be at least halved (unlikely in real terms I guess in the foreseeable future) then that option is a non-starter.


So I shall sleep on this idea FTB but thank you for your clearly explained thoughts- as to the SPD, I believe I understand the concept and if I were to proceed then this additional cost for the sake of a 'belt & braces' approach wouldn't be a barrier
 
Very good point, and to some extent my main concern with AFDD that you are not necessary spending money very wisely if there are other issues that present a higher risk of fire or shock and/or can be addressed cheaper than spending ~£2-3k on a new CU full of AFDD as the first option:
  • Old/poor cable condition
  • Lack of RCD protection
  • Incorrect overload protection (e.g. wrong fuse wire)
  • Dodgy appliances that ought to be recalled/scrapped
  • Hideous arrangements of extension leads due to a lack of planned sockets
  • No (or very basic) fire/smoke alarm provisions
  • Nothing in the way of fire blanket/extinguisher is high risk areas like kitchen/garage/workshop
  • Furniture that is high risk of fire and/or toxic fumes
  • Smoking (yes, it is a free and personal choice, but a poor one...)
Folks, open to discussion!
None of the above here, as the house has had a lot of electrical and other work properly done it appears but sadly without production of an EICR which I sought from the seller before I recently moved in, but is now in hand
 
Please don't think me discourteous as I really do appreciate pc1966 and catdog1121 input which has been helpful but my other issue, which you can't help me with and neither can SKY is that my landline phone and broadband is driving me nuts- the previous owner reputedly had at least two Openreach engineers to resolve problems in recent times and since September when I moved in I've had 4 more, and even now another attempt at providing me with a reliable signal thus avoiding the endless series of outtages, dropped connections, interrupted connections requiring reload, inability to login to my bank account and other regular destinations, is in train and more new equipment is awaited to attempt a satisfactory result- I'm not holding my breath for that result BUT out of necessity I shall keep my broadband usage to the very minimum ( even my mobile signal here is intermittent and that is an EE service!) and may not be back this way for a long time :(
 
Please don't think me discourteous as I really do appreciate pc1966 and catdog1121 input which has been helpful but my other issue, which you can't help me with and neither can SKY is that my landline phone and broadband is driving me nuts- the previous owner reputedly had at least two Openreach engineers to resolve problems in recent times and since September when I moved in I've had 4 more, and even now another attempt at providing me with a reliable signal thus avoiding the endless series of outtages, dropped connections, interrupted connections requiring reload, inability to login to my bank account and other regular destinations, is in train and more new equipment is awaited to attempt a satisfactory result- I'm not holding my breath for that result BUT out of necessity I shall keep my broadband usage to the very minimum ( even my mobile signal here is intermittent and that is an EE service!) and may not be back this way for a long time :(
Ah, we know the feeling well :(

We have been trying to get fibre since Aug 2020 and only now is it happening after we put in our own duct for around half a kilometre (partly to save time, partly to save cost).

If you have to rely on mobile broadband at home for any length of time you might want to look at the likes of this kit:

Providing you can fix it sensibly high and pointing in the right direction outside it can give you a reasonable link. It is powered via the network cable to it (kit has PoE injector) and ideally that should be outdoor UV-resistent cable, but for a few months usage then any CAT-5e or CAT-6 cable ought to do.

Cost per GB of data might be high depending on the SIM card deal used, etc, but it would be a work around until the jokers at Openreach fix the local infrastructure. Or you can get/afford fibre to the premises.
 
Each year over two million fires erupt all over Europe. More than one third of these due to faults in the electrical installation which prevailingly occur as a result of dangerous arc faults. S-ARC1 and DS-ARC1 provide maximum safety in all buildings, thus protecting people and valuable assets. By early detecting arc faults and disconnecting the affected circuit they offer reliable and complete protection in any type of building. so do RCD and rcbo.
I'm always suspicious of stats like these that conclude we would all be a lot safer with AFDD's once you have had a fire how do you identify the cause as an arc fault from the charred remains and it is pure assumption that an AFDD would have saved the day

From looking at past fire stats some years ago they are not that detailed and generally there is no in depth analysis of the cause so a lot of vaguely similar occurrences are generally lumped together which can distort the figures
 
I'm always suspicious of stats like these that conclude we would all be a lot safer with AFDD's once you have had a fire how do you identify the cause as an arc fault from the charred remains and it is pure assumption that an AFDD would have saved the day

From looking at past fire stats some years ago they are not that detailed and generally there is no in depth analysis of the cause so a lot of vaguely similar occurrences are generally lumped together which can distort the figures
That is my concern on the value-for-money front: that a lot of "electrical fires" would not be stopped by AFDD at all. For example, the various white goods that have fires unrelated to arcing (e.g. lint build up in those tumble dryers) or the likes of high power showers and poor joints where it is thermal heating and not an arc.

Now some folk would use the "if it saves one child!" sort of argument, but the reality is people have finite resources to spend and if an AFDD setup is mandated and unaffordable then work might not be done that would deal with far more fundamental electrical risks. Or they get some cowboy to do it and end up with something far less safe as a result.

If AFDD were really that good, surely we would have such detailed analysis to justify them?
 
£189 + VAT???? that's about 5 week's worth of diesel, 2 week's worth of smokes, and a couple of days worth of beer. AFDDDs. no thanks.
 
other day passed a Shell. £1.59/l

sainsburys £1.42/l

who's the rip off merchant?

atm i do about 150 miles /week, that's 5 gallons in my hiace. about £35. (unlees i'm daft enough to use shell).
 

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