Replacing fused spur

[Taylortwocities]

You may find that connecting 2.5mm t&E onto a light switch is a challenge. They are made for 1mm or (at most) 1.5mm conductors.

 

[JohnW2]

You may find that connecting 2.5mm t&E onto a light switch is a challenge. They are made for 1mm or (at most) 1.5mm conductors.

Possibly, which is one reason why I suggested a pair of grid switches, on a 1-gang plate, as an alternative. However, having said that, I see that the terminals of most MK light switches are 'rated' to take 3 x 2.5mm² conductors!

Kind Regards, John

 

[ban-all-sheds]

it means everytime we want only the under cabinet lighting on, the transformer will be powered up but not powering anything.

That doesn't make sense - if the transformer is powered up, the lights it is driving will come on, unless you remove all of the bulbs.

 

[PrenticeBoyofDerry]

If yo can manage to get a second cable up, without troubling the tiles, it is not that difficult to cut in to wall tiles and sink either another single box or extend existing to double gang with grid mods, or a dual outlet box with FCU and DG switch.

 

[Iggifer]

can't say I've ever really considered it before, but this fuse holder is for 1362 fuses

http://uk.farnell.com/bulgin/fx280/fuse-holder-in-line-1-x1-4/dp/287120

I'm sure it wouldn't comply with 7671 though

 

[JohnW2]

can't say I've ever really considered it before, but this fuse holder is for 1362 fuses ...

Are you contemplating try to get that into the back box (the depth of which we haven't been told!) behind the switches? Even if it could be fitted in, some very clear labelling would be needed, since this 'hidden fuse' could result in a subsequent householder or electrician pulling out a lot of their hair!!

I still don't really understand why most people are seemingly so disinclined to 'condone' the OP's proposed approach. In the absence of a fault in the cables between switches and FCUs, the only current which can pass through the terminals of the switch would be that passing through the outgoing cable and downstream FCU to the load - and, as we all know from Electricity 101 (or Mr Kirchoff), from the point of view of overload protection of that current path, it doesn't matter a jot as to whether the fuse is upstream or downstream of the switch. As for the (very unlikley) possibility of a fault in the cable between switch and FCU, it is very likely (and could be confirmed by measurement and calculation if one really wanted) that the circuits main protective device (32A MCB or whatever) would provide adequate fault protection for that cable - and, if so, the whole arrangement would be essentially BS7671-compliant.

Kind Regards, John

 

[deadshort]

Hi, do you have 2 separate cables leaving the existing fcu? As has been advised, you must retain the fusing down BEFORE the 2g switch.

Regards,

DS

The reason for my question was simply to offer a potential solution to the problem.
If you have two cables leaving the fcu i.e. 4 wires you could use 2 as switch wires and 1 as a feed by fitting a join box on the top of the cupboard taking a lighting supply to the join box on the top of the cupboards.\\

The feed to the existing fcu would be redundant and disconnected at the back of the socket it's spurred from.

DS

 

[JohnW2]

The reason for my question was simply to offer a potential solution to the problem. If you have two cables leaving the fcu i.e. 4 wires you could use 2 as switch wires and 1 as a feed by fitting a join box on the top of the cupboard taking a lighting supply to the join box on the top of the cupboards. ... The feed to the existing fcu would be redundant and disconnected at the back of the socket it's spurred from.

Can you help? - I'm struggling to understand what you are proposing. With your proposal, where would the FCU(s) be and where would the switches be - and if the 'existing FCU' were disconnected from it's source, where would all this be getting it's power from?

Are you perhaps suggesting that (if possible) an FCU be interposed in the feed to the existing FCU, and that this 'existing FCU' be changed to a 2-gang switch. If that were possible, and if there were two cables leaving the CU, then surely one cable could go to each light (neutral looping through the new switch), without the need for a 'join box', couldn't it?

Kind Regards, John

 

[sparkwright]

Why not leave the switched fused spur where it is, and leave it switched on.

And have a 2 gang switch with a shallow pattress mounted on the bottom of a nearby wall cupboard, which would be supplied from the fused spur unit.

?

 

[JohnW2]

Why not leave the switched fused spur where it is, and leave it switched on. ... And have a 2 gang switch with a shallow pattress mounted on the bottom of a nearby wall cupboard, which would be supplied from the fused spur unit.

As you will have seen, I've already partially made that suggestion, and the OP responded:

Regarding the switched left on and powering two switches I have no where else to put the light switches that is easily accesible as the cabling goes behind the cabinet and up to the top of the cabinets where the transformers etc are. The wall is tiled which makes things even harder.

... however, your suggestion of a shallow switch beneath a wall unit might be a viable solution.

Kind Regards, John

 

[stevepbuk]

it means everytime we want only the under cabinet lighting on, the transformer will be powered up but not powering anything.

That doesn't make sense - if the transformer is powered up, the lights it is driving will come on, unless you remove all of the bulbs.

Hi, sorry I wasnt clear in the original post. There is a WIFI LED controller between the power supply and the strip lights which allows you to turn them off.

Thanks

Steve

 

[stevepbuk]

can't say I've ever really considered it before, but this fuse holder is for 1362 fuses ...

Are you contemplating try to get that into the back box (the depth of which we haven't been told!) behind the switches? Even if it could be fitted in, some very clear labelling would be needed, since this 'hidden fuse' could result in a subsequent householder or electrician pulling out a lot of their hair!!

I still don't really understand why most people are seemingly so disinclined to 'condone' the OP's proposed approach. In the absence of a fault in the cables between switches and FCUs, the only current which can pass through the terminals of the switch would be that passing through the outgoing cable and downstream FCU to the load - and, as we all know from Electricity 101 (or Mr Kirchoff), from the point of view of overload protection of that current path, it doesn't matter a jot as to whether the fuse is upstream or downstream of the switch. As for the (very unlikley) possibility of a fault in the cable between switch and FCU, it is very likely (and could be confirmed by measurement and calculation if one really wanted) that the circuits main protective device (32A MCB or whatever) would provide adequate fault protection for that cable - and, if so, the whole arrangement would be essentially BS7671-compliant.

Kind Regards, John

The backbox is 25mm but there is small cavity around the box that I could put the inline fuses.

The solution above seems my best option. Thanks to all of you for your help.

Kind Regards

Steve

 

[deadshort]

Hi, sorry that's a bodge.

Regards,

DS

 

[ban-all-sheds]

Hi, sorry I wasnt clear in the original post. There is a WIFI LED controller between the power supply and the strip lights which allows you to turn them off.

Is the entire system designed together to work like that?

 

[JohnW2]

The backbox is 25mm but there is small cavity around the box that I could put the inline fuses. ... The solution above seems my best option.

As DS has said, that would, IMO as well, be an unpleasant bodge. Having an in-line fuse outside of the back box would make it even worse - and, in any event, how could one then get access to that 'cavity around the box' to change the fuse? As I've said, apart from anything else, any arrangement like that could be a nightmare in the future for anyone who doesn't realise that there is a fuse hidden away somewhere.

There is no where that I would have anything like that in my house, or any house I had anything to do with!

Kind Regards, John