Spot the ball

davesparks · Feb 19, 2015

pennychew said:
Read an interesting point earlier when I googled this situation... 'A socket and unswitched plug would be compliant as you have to remove the plug to isolate but a switched socket could only be single pole so not providing complete isolation' it was on the iet forum and makes an interesting point.

I'd still put it on an FCU though [emoji1]

Whether the socket is switched or not you isolate by removing the plug!

An FCU would not normally be used for a domestic boiler supply, it would normally be an SFCU. An FCU is a fused connection unit which would provide SP isolation by removal of the fuse and an SFCU is a switched fused connection unit.

pennychew · Feb 19, 2015

davesparks said:
Whether the socket is switched or not you isolate by removing the plug!

I know that! the point they were making was that someone could switch the socket off and begin working on the boiler/appliance thinking it was isolated when it wasn't.

Just wanted to put it out there!

davesparks · Feb 19, 2015

pennychew said:
I know that! the point they were making was that someone could switch the socket off and begin working on the boiler/appliance thinking it was isolated when it wasn't.

Just wanted to put it out there!

With the socket switched off it would be isolated (subject to confirmation by testing), it would just be a better option to remove the plug as it is far better for preventing it being accidentally switched on.

davesparks · Feb 19, 2015

telectrix said:
i prefer them on a FCU, if only for the fact that some dumb mrs mop might unplug boiler to use a vac. a socket outlet provides a compliant means of isolation, so would comply with regs. tin hat ready.

I prefer them on an SFCU as I don't like the idea of people having to manually pull a fuse out of a FCU, possibly breaking load current, to switch something off.

pennychew · Feb 19, 2015

Sorry i did mean SFCU, i would usually call it a switched fuse spur but was trying to use the proper terminology and got it wrong! DOH!!

davesparks · Feb 19, 2015

I would normally call a SFCU a switchfuse and a FCU a fused point because that's what my mentor called them when I was an apprentice. But swing as how this is the trainee section and impressionable young minds will be reading this it seemed sensible to get the terminology right

Silly Sausage · Feb 19, 2015

See Table 53.4 (BGB). Both switched and UNswitched are allowable for isolation.

I should imagine that it means removing the plug!

pennychew · Feb 19, 2015

Archy Styrigg said:
See Table 53.4 (BGB). Both switched and UNswitched are allowable for isolation.

I should imagine that it means removing the plug!

I'm afraid i only have the BRB but its downstairs and I'm in bed and its toasty warm so theres no way I'm checking it tonight!

newtothis · Feb 19, 2015

telectrix said:
only for the flex being tight up agin hot pipes.

ha ha I'll take that

That cable on unswitched socket went up to the hot cupboard into what looked to me like some kind of surface mounted junction box the size of a double socket with 35mm box ?? The power to the immersion heater came from that.

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