UK Domestic kitchens

[Toshie]

When wiring a domestic kitchen is ok to supply integrated appliances from 32A/ 2.5mm ring via 20A D.P. Multi grid Switches , using 2.5mm on out going side of switches to a 1 gang socket or spur ?

 

[Soi disant]

Yes, subject of course to the normal loading considerations for ring finals.

And BTW - you don't need to use 2.5mm² on the load side.

 

[Midwest]

That’s how a lot of new builds are done. Although I think there’s a few on here who don’t like using 20A DP switches protected by a 32A ocpd.

 

[UNG]

When wiring a domestic kitchen is ok to supply integrated appliances from 32A/ 2.5mm ring via 20A D.P. Multi grid Switches , using 2.5mm on out going side of switches to a 1 gang socket or spur ?

Are you putting in a ring solely for the integrated appliances?

 

[littlespark]

Consider radial circuit for each appliance over 2kW. Can still use the same bank of switches, but more than one circuit supplying.

 

[Dustydazzler]

Some appliance manufacturers specify a 16a over current device. So if you are strictly following the M.I then putting the appliance directly on a 32a ring is not correct.
of course the appliance will work hardwired directly to the 32a ring and I have done this on occasion but technically it’s not correct unless fuses down to the correct rating

 

[Taylortwocities]

Some appliance manufacturers specify a 16a over current device.

Yes, usually those appliances that are designed for EU where the 16A radial is the norm.

 

[Soi disant]

That’s how a lot of new builds are done. Although I think there’s a few on here who don’t like using 20A DP switches protected by a 32A ocpd.

Do they mind using BS 1363 sockets which only have to cope with 20A in the cable?

 

[Midwest]

Do they mind using BS 1363 sockets which only have to cope with 20A in the cable?

I don’t know, it’s not something that concerns myself. Have same set up in my house, and I don’t see any issues personally.

 

[littlespark]

A grid switch set up is totally compliant. It’s just spurs off an rfc.... although branched off very close together within the same box.
As with any infused spur, you can feed a double socket... but not usually done in a kitchen environment... single sockets only.


The above is for a “standard” rfc 32A OCPD

 

[Strima]

That’s how a lot of new builds are done. Although I think there’s a few on here who don’t like using 20A DP switches protected by a 32A ocpd.

Never understood that myself as a standard domestic appliance would never draw anywhere near 20 amps. I think they assume that the DP switch would have 32 amps flowing through it rather than just the supply side terminations taking the current.

 

[Ian1981]

20 amp DP switches are used on the grid for isolation/maintenance purposes only, nothing to do with having only 20 amps max through the switch or whatever as installing a fuse or a fused connection unit would be pointless considering the appliance plug has a fuse inside it.

 

[Ian1981]

Some appliance manufacturers specify a 16a over current device. So if you are strictly following the M.I then putting the appliance directly on a 32a ring is not correct.
of course the appliance will work hardwired directly to the 32a ring and I have done this on occasion but technically it’s not correct unless fuses down to the correct rating

The plug has a 13 amp fuse in it so that’s not technically accurate, more like the instructions cater for the European 16amp socket arrangement where there is no fuse inside a plug.

 

[Dartlec]

20 amp DP switches are used on the grid for isolation/maintenance purposes only, nothing to do with having only 20 amps max through the switch or whatever as installing a fuse or a fused connection unit would be pointless considering the appliance plug has a fuse inside it.

The grid switches in many of the late 2000s new build flats I've been in recently all have fusing at the grid switch - but I think when new they had appliance outlet plates at the appliance so no fused plug.

That may have been to avoid having to put them on the RCD side in the CU, or because they thought it was neater - but most have since been replaced with single sockets since they're almost all rented and tenants prefer to plug a fridge in....

 

[streamer]

And BTW - you don't need to use 2.5mm² on the load side.

Out of interest, in what circumstance would you not need to use 2.5mm on the outgoing side? And even if you didn't need to, why wouldn't you?

 

[littlespark]

Out of interest, in what circumstance would you not need to use 2.5mm on the outgoing side? And even if you didn't need to, why wouldn't you?

I suppose if it’s 13A fused you could go to the outlet in 1.5mm..... but normality insists it should be 2.5

 

[Soi disant]

Out of interest, in what circumstance would you not need to use 2.5mm on the outgoing side?

When the cable is

a) Adequately protected from overload by a downstream device and/or the nature of the load.
b) Adequately protected from faults by the upstream device.

And even if you didn't need to, why wouldn't you?

To avoid waste, and have an efficient design.

Looked at the other way, why would you use an oversized cable?