Use of 20AX switches in spurs off ring main

[Darkwood]

It is not a requirement or really necessary as isolation can and should be done at the CU. Local isolators are not fitted in other countries and they don't have any problems.

I can list you an entire manual of what they don't do in other countries as that is not really a strong argument to back your position, the reason I didn't specify a regulation is because there is no direct reference to one in the BS7671 although there is indirect regulations like following manufacturers guidelines which in reference to built in and heavy electrical appliances do recommend they are isolated before been removed be it or maintenance and replacement etc.
I do not understand your position in this debate tbh, if this is anything else in any other industry then you would need to disconnect supply before moving a machine/appliance yet you are taking the angle that this can be ignored in the realms of the domestic install.
When I was house-bashing some 20yrs ago we added a local means of isolation for large or heavy appliances if the outlet was not readily accessible and always if built in, to think you are arguing the opposite case some 2 decades later is worrying to be honest.
Following manufacturers guidelines is set into the BS7671 and has been for a while now so one should be designing install to account for the possiblilty that an appliance (if not already on site) may recommend a remote means of isolation.

Here is one of plenty of references to back up my angle on this http://www.nhbc.co.uk/Builders/Prod...uidanceDocuments/81/filedownload,65384,en.pdf

 

[Midwest]

To be fair to @GeorgeCooke, I've seen his argument posted before by many other sparks on this forum, so his opinion isn't isolated (excuse the pun )

 

[Darkwood]

@Midwest
I agree but the BS7671 then added a regulation to follow manufacturers guidelines which swung the debate from a personal choice to a recommended practice, since we don't always know what will be fitted in a unit or space then one needs to take the route of possible recommendation of the manufacturer once the appliance is bought, as for the inbuilt appliances then personally I take the view they should always have local accessible means of isolation as it can be the case that flexes get trapped under the appliance and make removing them while powered a potential for damaging the flex and also the risk of them dropping or falling over/down while been removed is also a reason to ensure they are isolated first, you shouldn't expect non trade people to start isolating full circuits to achieve this.

 

[Midwest]

@Midwest
I agree but the BS7671 then added a regulation to follow manufacturers guidelines which swung the debate from a personal choice to a recommended practice, since we don't always know what will be fitted in a unit or space then one needs to take the route of possible recommendation of the manufacturer once the appliance is bought, as for the inbuilt appliances then personally I take the view they should always have local accessible means of isolation as it can be the case that flexes get trapped under the appliance and make removing them while powered a potential for damaging the flex and also the risk of them dropping or falling over/down while been removed is also a reason to ensure they are isolated first, you shouldn't expect non trade people to start isolating full circuits to achieve this.

Easy tiger, was just saying. I prefer the socket in adjacent cupboard combo me self.

 

[SJD]

I would just add, that if you have a socket circuit with a fault, causing an RCD to trip for example, it is really handy to be able to switch off every appliance with a DP switch, to eliminate it.

Much easier than telling the customer they have to pull all the appliances out to get at the plugs.

 

[Toneyz]

Re the argument about above worktop isolators; a lot of my customers didn't like them, so a socket in an adjoining cupboard is sufficient.

Re the OP's question; App 15 is the informative guide to spurs off RFC. Would a 20A DP switch, followed by a 13A socket could be construed as more than outlet? Done it loads myself, but perhaps thats his sparks thinking.

No because the outlet is the socket.you don't count a single switched socket as two.

 

[Toneyz]

"Oh no! Theres a strong burning smell coming from my washing machine.... What do I do?!!?"
"Quick, turn off the power... theres a switch marked washing machine"
"OK, got it.... Wow, that was so easy"

OR

"Oh no! Theres a strong burning smell coming from my washing machine.... What do I do?!!?"
"Quick, turn off the power... Uhhhh…. no switch? … Wheres the consumer unit!"
"Um... Its under the stairs.... behind the bucket... its in a little cupboard... You have to wiggle the latch to get the door open.. Its not got little flicky switches... just pull the fuse"
"Yeh… I think I got it.. which fuse?! Nothings marked!"
"I dunno!.... Oh no... flames!.."

Isolation switches;- Not a requirement, but damn convenient in a crisis.

What about the socket in the cupboard or bank of spurs in a cupboard as I see on a lot of these youtube video's .it's local but you still have the problem if not mounted in the correct position being behind items in cupboards.
I know this is an old-fashioned view or not P.C. but years ago usually the man in the house used to know where the main stop taps for the water, gas and electric were today you go into someone's house and ask as that's usually where the bonding is they don't know same for the isolators for kitchen appliances long have the days gone that the kitchen was a room of functionality we want all these things out if sight.

 

[davesparks]

So what? There is no requirement for isolators anywhere, so the CU can be used.

Well in this particular thread we clearly have a customer who wants isolators installed, so what does it matter whether they are required or not? If the customer wants them fitted they can have them fitted.

 

[davesparks]

How on earth do you switch appliances off when they are not in use if the only means of switching is behind the appliance or turning the whole circuit off at the CU?

 

[Deleted member 26818]

I bought a number of 20AX grid switches with printed labels on them e.g. washing machine. These were to put an isolator above the work top for a 13A switched socket under the work top in the utility room. Electrician says no as the spur will be off a 32A ring the switch must be capable of the ring rating not the spur (single 2.5mm2 T+E). I can almost see his point but most suppliers have a range of printed 20AX but none for 32A so you end up with an unlabelled switch or a stuck on label which is not great. Any views on this? Thanks.

The electrician is incorrect.
The rating required for a standard RFC is 20A.
Tell the electrician to read Regulation 433.1.204.

 

[Deleted member 26818]

"Oh no! Theres a strong burning smell coming from my washing machine.... What do I do?!!?"
"Quick, turn off the power... theres a switch marked washing machine"
"OK, got it.... Wow, that was so easy"

OR

"Oh no! Theres a strong burning smell coming from my washing machine.... What do I do?!!?"
"Quick, turn off the power... Uhhhh…. no switch? … Wheres the consumer unit!"
"Um... Its under the stairs.... behind the bucket... its in a little cupboard... You have to wiggle the latch to get the door open.. Its not got little flicky switches... just pull the fuse"
"Yeh… I think I got it.. which fuse?! Nothings marked!"
"I dunno!.... Oh no... flames!.."

Isolation switches;- Not a requirement, but damn convenient in a crisis.

Switches used for emergency switching, must comply with the requirements for emergency switching.
i.e. should be red in colour, placed in a prominent position, must not be able to re-energise whatever has been switched off, etc.

 

[GeorgeCooke]

How on earth do you switch appliances off when they are not in use if the only means of switching is behind the appliance or turning the whole circuit off at the CU?

You don't need to, but if you must the front panel.

 

[telectrix]

if your electrician has an issue with the switches and the supply cable to the load not being protected why no incorporate a FCU module into the grid switch?

or find a different spark, one with more than a single brain cell.

 

[GeorgeCooke]

@Midwest
I agree but the BS7671 then added a regulation to follow manufacturers guidelines which swung the debate from a personal choice to a recommended practice,

So what do you do when the manufacturers guidelines are clearly wrong which is often the case? The example below is from a Cooke & Lewis oven purchased in B & Q only last week.

 

[Deleted member 26818]

My understanding, is that BS7671 requires Manufacturer’s instructions to be taken into account.