FCU connected to ring main

[masona]

I want to take out a single socket above the worktop which is on a ring main and replace it with a FCU and run a cable in a conduit to another socket under the worktop and plug the washing machine there, I just want to tidy it up and do away with the plug and cable through the worktop. The idea of the FCU so we can switch it on/off

Have read you can use the FCU on a ring main but want to double check

 

[EFLImpudence]

You don't need an FCU as there will be a fuse in the plug.

Just use a 20A double pole switch

 

[17thman]

I suppose the idea of a switched fused spur would be that, without test equipment, the OP would not know if the the junction point was actually on the ring final circuit. It sort of covers things if that point was a spur feeding another spur.

 

[EFLImpudence]

I suppose the idea of a switched fused spur would be that

I don't think there is an 'idea' of a switched fuse spur.
I presume that is just what was thought should be done.

without test equipment, the OP would not know if the the junction point was actually on the ring final circuit. It sort of covers things if that point was a spur feeding another spur.

Not really, if it were already a spur, it would make no difference.

 

[masona]

You don't need an FCU as there will be a fuse in the plug.

Just use a 20A double pole switch

Thanks, the washing machine plug will be in the new position underneath the worktop out of sight, not sure how a 20A double pole switch will turn the washing machine off above the worktop. Not sure where do you plug the washing machine.

There is no spur just a ring main with a single socket above the worktop

 

[securespark]

You don't need an FCU as there will be a fuse in the plug.

Just use a 20A double pole switch

Be careful!

Last time I suggested that, I got shot down...

Apparently the 20A rating isn't enough for the ring current flowing through...

 

[RF Lighting]

Technically it's a none compliance as it's not listed as a device suitable for use on a ring final circuit according to the BGB.

Personally I wouldn't worry too much about it though.

 

[securespark]

Is the reason I've listed why?

I mean, would a 32A switch be compliant?

 

[EFLImpudence]

Thanks, the washing machine plug will be in the new position underneath the worktop out of sight, not sure how a 20A double pole switch will turn the washing machine off above the worktop.

It's a switch.

Not sure where do you plug the washing machine.

At the new socket you want to install, wired from the output of the switch.

It's just that you don't need two fuses for one appliance.


I understood you wanted a switch above the worktop, as is the fashion nowadays.

The idea of the FCU so we can switch it on/off

If not, just connect the spur to the existing socket.

 

[EFLImpudence]

You don't need an FCU as there will be a fuse in the plug.

Just use a 20A double pole switch

Be careful!

Last time I suggested that, I got shot down...

Apparently the 20A rating isn't enough for the ring current flowing through...

I've never heard that.

Why not? That is all the rating of the cable and accessories have to be.
What is the rating of an FCU? - or a 13A DSO.

There will only be 13A maximum running through the switch.

 

[RF Lighting]

Is the reason I've listed why?

I mean, would a 32A switch be compliant?

Regulation 433.1.5 only lists BS1363 devices as being acceptable to be supplied from a RFC, and AFAIK this standard only applies to 13A socket outlets, and FCUs.

 

[EFLImpudence]

Regulation 433.1.5 only lists BS1363 devices as being acceptable to be supplied from a RFC, and AFAIK this standard only applies to 13A socket outlets, and FCUs.

Interesting: can't dispute.

So, because they are BS3676 (switches) they are not allowed - fair enough.
FCUs, even switched ones, from the same manufacturer (presumably made the same) are BS1363.

No more grid switches - BS60669

Personally I wo...n't worry too much about it though.


However, I assume they would be allowed on a 32A radial with the same current characteristics.

 

[westie101]

I would suspect that as it would be in the ring, the restriction is on the rating of the input terminals

 

[JohnD]

anyway...

you can fit a switched FCU if you want. Appliances fuses blow approximately zero times per lifetime, so the theoretical possibility that the plug fuse will blow and the FCU fuse will not is insignificant

If the fuse ever does blow, the appliance will probably have to be pulled out to throw on the skip or to mend it anyway.

 

[EFLImpudence]

I would suspect that as it would be in the ring, the restriction is on the rating of the input terminals

That can't be it because it's exactly the same on a radial and would only be 13A maximum - unlike a double socket.

I would suspect there is no good reason other than the numbers printed in 433.1.5.