Kitchen wiring plans

[DanGB]

Hello all, love this forum, really helpful!

Whilst re-doing the kitchen i'm replacing the messy wiring and adding/replacing some sockets.

Here is the plan. Let me know if you think it looks ok.

Everything above the brown worktop is chased in, everything below is just tacked to the wall.

I was having a bit of trouble planning the wiring and spur /light switch for the under cabinet lighting, so any suggestions on that would be good.

Many thanks!!!

 

[EFLImpudence]

It is pointless having a ring where the outward and return paths are in the same place.

Use 4mm² T&E (with the 30A/32A protection) and just have a radial circuit - i.e. one run and branches.

I like to have the cooker hood on the cooker circuit but that's up to you.
Also, you may prefer two single sockets at the dishwasher position; double sockets don't like two large appliances.

 

[DanGB]

Ok Thanks That's interesting. I always thought it would be better to have a ring where possible to help spread the load as such, especially where we have high drain appliances like the washing machine, dishwater, microwave oven and kettle. This is why I like coming here to get viewpoints.

I was planning to go for ring as its already connected to the CU like that and goes under the flow to the CU, but nothings set in stone (but it is set in concrete ) pun intended.

 

[John D v2.0]

Actually it's not a viewpoint - a radial doesn't have a concept of unbalanced loads - if you have a radial then all cables can handle the full load so no chance of an imbalance, but if you have a ring then it's assumed that much of the load is at the centre of the ring, and the rest is distributed evenly. Put all your load at one end of a long ring, and you'll overload the shorter cable to the CU.

Edit: the only benefit of a ring is saving cable as you can do a circuit (topologically speaking) of the area served and back to the origin from the other direction. There are also disputed benefits about redundancy of CPCs.

 

[JohnD]

Rather than have your appliance sockets under the worktop (where you can't readily get at them to turn them off) you can have a switch above the worktop controlling an unswitched socket below. Appliance sockets are better as singles. You can put in extra ones at any position where you might one day want an appliance.

Also, if you are hacking out the wall above the worktop for a row of switches and sockets, I see no reason to have the cables popping up and down from underneath. You can cut out all your socket boxes and chase horizontally between them for the cable. Your FCU for the extractor, worktop lighting, kitchen TV (and perhaps the boiler) can be in the same row, feeding a flex outlet vertically above. If you run the cable in oval conduit, it is very easy to cut in another socket box later, when you realise you have insufficient.

v2.
rings do not have ends.

 

[John D v2.0]

If anyone was confused by what the ends of a ring circuit are in that context, let me know and I'll draw a picture!

 

[DanGB]

Thanks all for your input so far.

There is already 2x 2.5mm coming from the Consumer unit as it was a ring before I tore it out. If I change it to a radial, I have to dig up the floor to replace the existing cable some distance.

If a radial is very much recommended now then thats fine, so my question here now is; does the radial have benefits in this type of situation to warrant the change? Or should the existing ring be kept.

 

[John D v2.0]

In that case keep the ring. If you're changing the whole cable it's debatable whether that's still a modification to an existing circuit or whether it becomes notifiable anyway.
Another option would be to join the two legs together where they come up, and attach your 4mm radial as effectively unfused spur.
However you would have to leave a good diagram at the CU to avoid someone in future extending the ring part inappropriately. Or just being extremely confused. You'd also need to check the lengths of the existing legs to make sure your radial is central.
In summary, keep the ring!

 

[DanGB]

In that case keep the ring. If you're changing the whole cable it's debatable whether that's still a modification to an existing circuit or whether it becomes notifiable anyway.

Yes I think there is a fine line being drawn here. I'm not touching the cables from the CU, but replacing the rest of the cable to tidy and adding some new spurs/sockets.

I am planning to get an electrician in to test/inspect.

 

[JohnD]

Your layout (with the ring returning the same way it went out) suggests that there are only sockets along one wall.

A ring is more sensible when it goes all the way round the room, with outlets at intervals on (about) four walls.

Is you kitchen an unusual shape?

Even if the other side is a Tall Wall of units, presumably it has a fridge Freezer, microwave or something?

the big advantage of a ring is that it allows you to have an unlimited number of sockets on one floor of an ordinary house, usually with great simplicity, and often no need to have bits hanging off it and wandering away in strange directions.

 

[DanGB]

Is you kitchen an unusual shape?

Well the kitchen is quite long and thin as it has been extended. So the main sockets are along the long side, plug a couple on the left side of the extension.

There is 1 double socket along the dining room wall as per below but its on the ground floor ring, not kitchen. There is nothing on this wall in terms of electrical devices.

Im basically copying the same wiring as before with some slight modifications. (Only just bought the house)

Here is the above diagram put into context:

 

[JohnD]

Does the kitchen have its own ring? Or is it the same as the adjacent room?

Are all your floors concrete?

 

[DanGB]

Does the kitchen have its own ring? Or is it the same as the adjacent room?

Are all your floors concrete?

Kitchen is its own ring yep!
There is an extra socket on the long wall next to the oven on a different circuit which the fridge freezer is plugged in to.

The floor is mostly concrete, some of it is floorboards! Its a 1930's house, but as I say the Kitchen has had the extension, hence the concrete.

 

[JohnW2]

the big advantage of a ring is that it allows you to have an unlimited number of sockets on one floor of an ordinary house ...

I don't see that as being peculiar to a ring.

Kind Regards, John

 

[JohnD]

...usually with great simplicity, and often no need to have bits hanging off it and wandering away in strange directions.