Is there a chance Dual RCD Consumers could be "banned " from rentals soon?

[LukeD]

I don't see it as a black and white issue. Kitchens are one obvious room where a number of power hugry appliances could be connected to a circuit it's not my place to determine what may or may not be connected. Of course it is perfectly possible to run a 32A radial, but in some instances it may be required that 6mm cable is used and that raises a number of potential issues.

It seems to me that quite a few electricians learn by rote, rather that reason and simply repeat what they have seen or heard from others. 'Ring circuits are terrible', 'radial circuits are the future', (neglecting to realise they far pre-date the ring circuits), 'wire rings in 2.5 cable', 'wire 32A radials in 4mm', 'showers up to 8.5kW are fine on 6mm' and on and on... this industry based on the laws of physics and guided by regulations, yet many seem unable to understand the most basic of those laws or take the time to understand regulatory guidance.

Don't get me wrong, I'm all in favour of minimising potential disruption for customers (which I believe should be at the front of everyone's mind when desiging an installation), but I'm also in favour of practicality and on many occasions this will mean the utilisation of the simple and efficient ring final circuit. If a general power circuit trips it won't matter one iota to the customer what size of cable it is wired in or whether the circuit is fully linear, branched all over the place or run as a ring - what will matter is whatever caused the problem can be resolved quickly, with a minimum and some reassurance that it won't happen again in the near future.

What I'd really like is for someone who believes ring final circuits to be old hat or problematic to explain the reasoning behind that thinking. The ring final is often ideal for general power circuits where significant loads may be applied. Assuming that circuit isn't serving a remote area of the property, where a return leg could be considered wasteful, the only argument I ever read in favour running a radial circuit is in the case of fault finding and that line of reasoning is usually based on the premise that radial circuits are linear and that ring final circuits are spurred off left, right and centre. A straightforward ring final should present little challenge for any competent electrician where fault finding is concerned. Conversely, reinstating power to a heavily modified ring may cause the loss of some hair, just as it may with a heavily modified ring final.

What about Individual RFC's for each room both sockets and lighting ? A single RCBO's can cover 3 x bedrooms sockets etc . But they still all"drop together " rather than only the one when an issue occurs . I agree with the testing Bit!

 

[nicebutdim]

What about Individual RFC's for each room both sockets and lighting ? A single RCBO's can cover 3 x bedrooms sockets etc . But they still all"drop together " rather than only the one when an issue occurs . I agree with the testing Bit!

I specifically mentioned circuits to which significant loads are likely to be applied. Using a ring to cover multiple rooms presents unnecessary inconvenience and disruption in the event of a fault, which I've stated is something I'd seek to avoid.

I've wired kitchens with separate radials for each appliance, but a ring final for general power. If an individual appliance develops a fault, then nothing else is taken out with it, the customer's inconvenience is minimal and they're able to get on with day to day life until someone can resolve the situation. Not every customer will have the budget for this, but the relatively small number of customers I've now worked for on my own have generally been happy to increase their budget by a small margin when options are offered and pros and cons presented.

I see no merit in dual RCD boards, except in some limited circumstances, with RCBOs being available at the low prices we have today. It should be pointed out that homes up and down the country enjoy a trouble free existence with dual RCD protection, but that enjoyment is significantly reduced when a fault occurs.

 

[Dustydazzler]

If I re-wire my next house I am going for 20amp radials for sockets 1 radial per room. and 3 maybe 4 radials for the kitchen.
no rings in sight

 

[nicebutdim]

If I re-wire my next house I am going for 20amp radials for sockets 1 radial per room. and 3 maybe 4 radials for the kitchen.
no rings in sight

Which may well be ideal for your property, but that's not to say it would be ideal for every property. Common sense dictates that we choose the best option for any particular set of circumstances, rather than blindly apply the same option regardless of circumstances.

I'd prefer to see my next property before deciding how it would be wired.

Last kitchen I wired had radials to washer, dishwasher, dryer, fridge freezer, immersion heater & boiler tap. 32A 6mm oven circuit which was overkill, but customer had ideas about bigger and grander in the future. Hob was spurred off a ring from its isolator (as was extractor), which otherwise served only kitchen sockets. What problems would you envisage with that?

 

[Mike Johnson]

Radials to white goods should be the norm, but the size of the CU's generally available in the UK will need to be increased, retro fitting could be a problem, one of the prolific video bloggers did recently ask if multi tier boards where the future, certainly in new builds they should be fitted as standard as should dual module RCBO's, but then that's only my opinion, makes testing and isolation so much easier.

 

[nicebutdim]

Even those manufacturers whose wares have traditionally been aimed at the continental European market are moving to single module RCBOs which switch both lines.

I like the compact form of our boards, although two row is becoming a more popular choice to fit as consumers demand more complex installations. For the average home a single row board can provide adequate ways, but architects/ builders often still need to better consider placement of boards.

 

[LukeD]

Which may well be ideal for your property, but that's not to say it would be ideal for every property. Common sense dictates that we choose the best option for any particular set of circumstances, rather than blindly apply the same option regardless of circumstances.

I'd prefer to see my next property before deciding how it would be wired.

Last kitchen I wired had radials to washer, dishwasher, dryer, fridge freezer, immersion heater & boiler tap. 32A 6mm oven circuit which was overkill, but customer had ideas about bigger and grander in the future. Hob was spurred off a ring from its isolator (as was extractor), which otherwise served only kitchen sockets. What problems would you envisage with that?

True...It has to be a case of what suits property and needs .

 

[timhoward]

Going back to AFDDs, the last couple of videos from DSES are interesting - he could not get a Hager AFDD to trip with visible arcing occurring.
(Unfortunately you have to tolerate the pointless bad language)

 

[newfutile]

Those videos were quite concerned im not sure I would specify Hagar after that when the Fusebox and Siemens seemed to work fine , while his testing was not that scientific I would have expected a trip with the series arc test

 

[pc1966]

Those videos were quite concerned im not sure I would specify Hagar after that when the Fusebox and Siemens seemed to work fine , while his testing was not that scientific I would have expected a trip with the series arc test

One of the big plus-points of the Hager AFDD is the bluetooth diagnostics and/or firmware updates for the devices. If something has occasional trips you really will struggle to get to the bottom of it as no MFT (to my knowledge) offer any independent means of testing an AFDD - we are expected to take the self-test as gospel.