AFDDs for single-socket circuits

[Selfmade]

Haven't been on here for a while, so sorry if this has been discussed before.

BS7671 2018 + A2 Regulation 421.1.7 recommends AFDDs for "single-phase AC circuits supplying socket outlets..." (requires in certain premises). My intention is that from September 27th I will recommend them to customers (in practice I already do in some situations) and require a signed waiver if they don't want the expense. At least I will do so for the actual Sockets Circuits - typically ring final, serving a number of sockets for general use and sometimes also fixed equipment via FCUs.

What I'm not sure about is circuits that serve just a single socket, such as a dedicated circuit for a fridge or an oven. In the case of a fridge, it will likely draw less than 2A, so an AFDD is unlikely to perform any useful function. In the case of an oven, one could justify cutting off the plug and connecting it via an FCU, in which case the circuit is no longer supplying a socket, yet with or without a socket it's still the same appliance and the same wiring. Yet in both cases if a socket is fitted an AFDD is recommended according to the regs.

BTW I understand a case could be made for AFDD protection for an oven and oven circuit. But for this question I'm just interested in the definition of 'circuits supplying socket outlets' for the purposes of this recommendation.

 

[timhoward]

I'll be honest - you have more enthusiasm than me!

Personally I'm not in a hurry to make the manufacturers any richer and I only fit them if required. Quoting for them for other jobs just makes me look (even more) insanely expensive compared to the chancers who fit the cheapest dual-rcd board they can find at Screwfix and bang test it.

I don't quite understand why you'd require signed waivers for something that is just a recommendation unless it's a scaremongering technique.
How will this work in practise, will you double the admin and quote for the job with and without them and then ask for a signed waiver if they choose the cheaper option?
Will you also ask for a waiver for other recommendations in A2, such as adding an earth electrode to a PME system?

 

[Dustydazzler]

Until I can fit an AFFDDD board for roughly the same price as I can currently install a full RCBO board then I ain't fitting AFFDDDs

Speaking to other electricians locally we don't want them and don't want to be forced to use them

 

[Selfmade]

I'll be honest - you have more enthusiasm than me!

Personally I'm not in a hurry to make the manufacturers any richer and I only fit them if required. Quoting for them for other jobs just makes me look (even more) insanely expensive compared to the chancers who fit the cheapest dual-rcd board they can find at Screwfix and bang test it.

I don't quite understand why you'd require signed waivers for something that is just a recommendation unless it's a scaremongering technique.
How will this work in practise, will you double the admin and quote for the job with and without them and then ask for a signed waiver if they choose the cheaper option?
Will you also ask for a waiver for other recommendations in A2, such as adding an earth electrode to a PME system?

Thanks for reply timhoward.

So here's my thinking: I'm ideologically in favour of giving the customer as much choice as possible. For a while I have, where appropriate, quoted for a 'bare bones' job as cheaply as possible (to secure the job), and offered optional extras / pricier options that people can choose if they wish, that gives me the chance to make some actual profit instead of just keeping things ticking over. I do find there are some people who just want the cheapest, and other people who will tick every box so to speak for all the extras. It's not always obvious to me who will be which, and I do think it should be their decision. So I quite like these recommendations rather than requirements.

The challenges are two-fold: how to explain the advantages of the more expensive options in language they can understand so they can make an informed choice, and how to cover myself in case something goes wrong at some point and someone turns round and accuses me for not 'following official recommendations' or such like (hence the waiver). Not a scaremongering technique - just wanting to be sure I'm covered.

Yes, that's how I intend to do it in practice. As I see it doubling the admin goes with giving people the choice. When I started out I used to ask people a lot of questions about what they wanted when I visited, but quickly realised they couldn't answer until they knew how much each option would cost. As for the other recommendations, yes, I've prepared a 'delete as appropriate' waiver covering each of SPDs, AFDDs and earth electrodes.

 

[Selfmade]

Until I can fit an AFFDDD board for roughly the same price as I can currently install a full RCBO board then I ain't fitting AFFDDDs

Speaking to other electricians locally we don't want them and don't want to be forced to use them

Ahhhh yes but the customer might want them and might be happy to pay for them. Who am I to make a value judgement on their cost/benefit analysis?

Personally if I was doing a CU in my own home I'd probably fit an AFDD for the kitchen sockets but not bother elsewhere.

 

[timhoward]

It’s always interesting to hear how other people approach their business. Thanks for sharing.
We agree on the point of helping customers understand complicated things using simple non technical terms. I’m quite passionate about that - if they are going to pay more for an RCBO board (for example) I want them to understand the benefits.

I think my struggle is that I’m not personally convinced AFDDs are going to save many lives. I’m aware of the argument that one life saved anywhere makes it worthwhile. But when nothing I’ve worked on over the last 20 years has had a subsequent electrical fire it’s hard for me to tell people it’s money well spent.
It feels more likely to be properties that aren’t being tested, inspected, and upgraded that need the AFDD technology the most and of course they are the ones that won’t get it.

I’m trying to keep an open mind about them nonetheless!

 

[Dustydazzler]

if houses and flats were burning down left right and centre due to loose connections and arc faults then I would be the first to be pricing AFFDDDs to my board swaps. My clients for most part are very well off and wouldn't bat an eyelid to a new £2000 consumer unit.
I just haven't seen enough evidence in front of me to suggest AFFDDDS are really a necessary Evil

 

[Selfmade]

It’s always interesting to hear how other people approach their business. Thanks for sharing.
We agree on the point of helping customers understand complicated things using simple non technical terms. I’m quite passionate about that - if they are going to pay more for an RCBO board (for example) I want them to understand the benefits.

I think my struggle is that I’m not personally convinced AFDDs are going to save many lives. I’m aware of the argument that one life saved anywhere makes it worthwhile. But when nothing I’ve worked on over the last 20 years has had a subsequent electrical fire it’s hard for me to tell people it’s money well spent.
It feels more likely to be properties that aren’t being tested, inspected, and upgraded that need the AFDD technology the most and of course they are the ones that won’t get it.

I’m trying to keep an open mind about them nonetheless!

You're welcome! And thanks also!

You may be right that they will not save many lives. And I'm not a proponent of the 'one life anywhere' argument - it may sound callous but what do we all eat if we put all our resources into saving one life? Everything is a risk/benefit analysis. It's a difficult judgement call with a fair bit of uncertainty, but IMHO one that should ultimately be the customer's. They might want to consider risk of damage to property as well as risk to life.

For me the recommendation in the regs is for the customer - the property owner is the duty holder at the end of the day. So if I don't tell the customer about the recommendation they could reasonably argue that I had been negligent in not giving them that information. That's where my waiver comes in - to prove I've informed them and they have made the choice.

That's a good track record you have. Thankfully I can say the same for my 10 years. Bare in mind AFDDs may have more to do with dodgy white goods than the fixed installation. Something I'd probably say to customers verbally rather than putting in writing with named manufacturers!

 

[Selfmade]

if houses and flats were burning down left right and centre due to loose connections and arc faults then I would be the first to be pricing AFFDDDs to my board swaps. My clients for most part are very well off and wouldn't bat an eyelid to a new £2000 consumer unit.
I just haven't seen enough evidence in front of me to suggest AFFDDDS are really a necessary Evil

Yes, but quite a few white goods. Including some high profile cases.

 

[Selfmade]

if houses and flats were burning down left right and centre due to loose connections and arc faults then I would be the first to be pricing AFFDDDs to my board swaps. My clients for most part are very well off and wouldn't bat an eyelid to a new £2000 consumer unit.
I just haven't seen enough evidence in front of me to suggest AFFDDDS are really a necessary Evil

Arc Fault Finding Damage Detection Devices?

 

[westward10]

You need to give more info such as the nature of the premises and whether afdds are actually required. Are you getting some crossover confusion with spds.

 

[UNG]

In the next few months I feel AFDD's are going to be one of the most debated parts of AMD 2 and lets not forget our colleagues across the pond have had AFCI's for many years and there seems to be a consensus that they don't always work as they should over there
When the AFDD first appeared 4 - 5 years ago with an eyewatering cost attached I was curious as to the benefits and if there were any negatives so at one or two of the Elex shows I spent some time talking to the manufacturer's of the devices and also the test equipment manufacturer's
As you would expect the manufacturer's who had AFDD's on display were very pro fitting them ( they would at £200 each) but aside from the test button on the front they had no external test equipment to demonstrate them like you would an RCD and you had to accept with blind faith that they would operate as the manufacturer's expected under fault conditions
Then we come to the test equipment manufacturer's and with the different arc fault signatures they said they had no way of verfying the operation of an AFDD or identifying the existance of a potential arc fault on the circuit and it's location on the circuit

So we fit an AFDD or multiple AFDD's on an installation and one trips what is the course of action, does the householder just reset it and let the problem develop and at what point do they get the electrician in. No doubt if the AFDD tripping icreases to the point of being inconvienient the electrician will be called and then the question is what can we do to check the operation of the AFDD and then the integrity of the circuit the answer I got from one test equipment manufacturer was replace the AFDD if that doesn't solve the problem then rewire the circuit.
Earlier this year I came across the Hager AFDD that can be reprogrammed but having seen it in the flesh at one of the shows and now having thought a bit more about what they said at the time it brings up more questions which I hope to get answered at one of the upcoming shows

I have to admit after 40+ years on the tools I'm quite sceptical of these AFDD devices I can only think of a couple of faults I have been called to in that time that MAY have been detected a bit earlier with an AFDD but then they may not

Bare in mind AFDDs may have more to do with dodgy white goods than the fixed installation.

So why is the onus being placed on the installation to prevent dodgy white goods causing problems it starts to blur the lines when it comes to PAT as to whether appliances should be tested as part of the EICR

 

[Selfmade]

You need to give more info such as the nature of the premises and whether afdds are actually required. Are you getting some crossover confusion with spds.

Thanks for reply - I should have been clearer, this doesn't relate to a specific job but is just me thinking around the issues. Most of the premises I work on are not 'high risk' or otherwise required to have AFDDs.

I'm aware of the fact SPDs are required unless the customer opts out, while AFDDs are only recommended, but I still think liability could arise if one can't prove the customer was informed of the recommendation and made their own choice.

 

[Selfmade]

In the next few months I feel AFDD's are going to be one of the most debated parts of AMD 2 and lets not forget our colleagues across the pond have had AFCI's for many years and there seems to be a consensus that they don't always work as they should over there
When the AFDD first appeared 4 - 5 years ago with an eyewatering cost attached I was curious as to the benefits and if there were any negatives so at one or two of the Elex shows I spent some time talking to the manufacturer's of the devices and also the test equipment manufacturer's
As you would expect the manufacturer's who had AFDD's on display were very pro fitting them ( they would at £200 each) but aside from the test button on the front they had no external test equipment to demonstrate them like you would an RCD and you had to accept with blind faith that they would operate as the manufacturer's expected under fault conditions
Then we come to the test equipment manufacturer's and with the different arc fault signatures they said they had no way of verfying the operation of an AFDD or identifying the existance of a potential arc fault on the circuit and it's location on the circuit

So we fit an AFDD or multiple AFDD's on an installation and one trips what is the course of action, does the householder just reset it and let the problem develop and at what point do they get the electrician in. No doubt if the AFDD tripping icreases to the point of being inconvienient the electrician will be called and then the question is what can we do to check the operation of the AFDD and then the integrity of the circuit the answer I got from one test equipment manufacturer was replace the AFDD if that doesn't solve the problem then rewire the circuit.
Earlier this year I came across the Hager AFDD that can be reprogrammed but having seen it in the flesh at one of the shows and now having thought a bit more about what they said at the time it brings up more questions which I hope to get answered at one of the upcoming shows

I have to admit after 40+ years on the tools I'm quite sceptical of these AFDD devices I can only think of a couple of faults I have been called to in that time that MAY have been detected a bit earlier with an AFDD but then they may not

So why is the onus being placed on the installation to prevent dodgy white goods causing problems it starts to blur the lines when it comes to PAT as to whether appliances should be tested as part of the EICR

Lots of interesting info, thanks. The issue of how to track down a fault is one thing that concerns me, too. I think I'd probably proceed something like this:

1. Ask the customer to switch everything off and see if it will reset. If so ask them to try to note over time if it trips when a particular appliance is switched on etc. If suspect appliances found try to move them to another circuit if possible to see if the fault moves with the appliance.

2. Try swapping the AFDD - with another in the same CU if one of the same rating is present. Then see if the fault goes with the AFDD or stays with the circuit.

3. Check for loose connections, dodgy switches etc. and tighten/replace as appropriate.

4. Examine all visible wiring of circuit in loft, basement etc.

5. Ask if the customer minds part of the circuit being temporarily disconnected to see if the fault persists.

6. Only rewire as a last resort.

A far from ideal situation for sure.

As for why the onus is placed on us, I have heard it said that it is because the manufacturers sit on the JPEL committee and essentially they want to keep selling Ch*n*se junk with western brand names on the front with impunity. Whether that is the case I have no way of knowing.

 

[Markyd]

Thanks for reply - I should have been clearer, this doesn't relate to a specific job but is just me thinking around the issues. Most of the premises I work on are not 'high risk' or otherwise required to have AFDDs.

I'm aware of the fact SPDs are required unless the customer opts out, while AFDDs are only recommended, but I still think liability could arise if one can't prove the customer was informed of the recommendation and made their own choice.

Yes AFDDs are only a recommendation but after September will need a waiver signed by the client to say they dont want them, which will cover you when their tv blows up and they say you didnt recommend using one