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From what I can gather, these grid switches can be crap. Burnt out, poor quality etc. is a common topic I'm picking up here. So, which companies to avoid etc.?
My fixer-upper house falls under the regs of new build and thus I need to isolate hidden appliances. In the kitchen, I was going to put two grid switches - one for the cooker/hob/extract, and one for Dishw and fridge. This is a logistics thing and a plan to avoid crammed-up wiring in a deep back box. The cooking area is 7 metres away from the "Wet" area of kitchen. All appliances 13 amp plugged.

The utility room is not part of the kitchen, other corner of the house in fact. It will have its own ring back to the consumer unit (I have the space and time to do this). None of the appliances in there will be built-in (Fridge, fridge/freezer, tumble drier, washing machine) but they will be under a worktop and the plug tops not accessible. So, I was going to put a Grid switch in, to perform the isolation function. But, on that ring, there will only be 1, maybe 2 sockets above worktop which will only be used rarely. So this circuit is essentially 4 spurred appliances and one socket. Is that OK? I could of course put an isolation switch above the worktop for each appliance but the grids look neater.
Comments?
 
Lots of folks with more domestic experience than me will hopefully comment, but if the appliance comes with a plug why not use it? For the utility room, I think it's ok that the outlet is behind the appliance and you need to pull it forward to unplug it. You would need to pull it forward to take the covers off for servicing anyway, and all would be revealed. As you are planning a ring I'm not sure how you would get isolation with one switch? Or why it's needed for non built in appliances?
 
I agree, there's really no need for separate isolation switches. Do you have a separate isolation switch for your TV? Your computer? I guess not, so why would you need one for plug-in boxes in the kitchen?

IMO its better to have the socket in an easy-to-get-to place (adjacent cupboard, eg) and just plug it in.

PS the largest capacity grid switch I have seen is 20amp, so that means you arent going to be able to use a grid switch for the hob, and probably not for the cooker either!
 
I agree, there's really no need for separate isolation switches. Do you have a separate isolation switch for your TV? Your computer? I guess not, so why would you need one for plug-in boxes in the kitchen?

IMO its better to have the socket in an easy-to-get-to place (adjacent cupboard, eg) and just plug it in.

PS the largest capacity grid switch I have seen is 20amp, so that means you arent going to be able to use a grid switch for the hob, and probably not for the cooker either!

In the utility, no cupboards. I'm designing it the correct size for the four units, worktop above will be on batons on 3 walls.
Good point on the telly pc etc but those plug tops aren't behind anything "Heavy" that would need dragging out whilst live (Shorted). I could put the plugs above worktop and feed through a hole in the corner of worktop....but not the best looking idea.

Cooker and hob are both 13 amp plugged, so is the extractor, all 3 will be on together so a 20amp is no use if 20 is max. 3 separate switches there then? Such a circuit is therefore a 13 amp fuse protected by a 20 amp fuse, with a circuit fault protected by an RCD in CU. But I have seen images of Grid switches labelled as Hob... fan... Oven?
 
The 20A is not a FUSED rating, only the plug has the fuse. The grid switch 20amp rating is the maximum current that the switch contacts can handle before they weld themselves together.
My other dislike about grid switches is when the grid switch 'cluster' is part of a ring final. Then all of those heavy loads are concentrated at one point on the ring and that is bad design. The idea of a ring final is for the loads to be distributed around the ring.
 
The 20A is not a FUSED rating, only the plug has the fuse. The grid switch 20amp rating is the maximum current that the switch contacts can handle before they weld themselves together.
My other dislike about grid switches is when the grid switch 'cluster' is part of a ring final. Then all of those heavy loads are concentrated at one point on the ring and that is bad design. The idea of a ring final is for the loads to be distributed around the ring.
Yes. Hence my original question about being 4 spurs. No, I don't like that idea at all. It's settled then, I will not use grid switches, I will have an isol. switch for each appliance and keep a traditional final ring. Well, two in my case. Then radials for boiler, immersion heater and shower if I fit electric one. They will all be radials direct from CU. And another ring for "Ordinary" downstairs.
Cheers, my decision is made.
 
I think the reason new builds have the grid switch arrangement is to comply with Part M. Do you have to with your refurbishment? I think either arrangement, 20 DP switches and socket under worktop or just socket under work top is okay. I agree with having the socket in an adjacent cupboard, if at all possible, especially with built in appliances. I would consider a kitchen/utility RFC or Radial as options.
 
PS there was a debate some time ago, about the cutting off of plug tops on appliances voiding warranty. Which was unfounded. However, when doing kitchen refurbs, we still drill hole larger enough to keep on the plug. Makes it easier to remove the appliance for maintenance etc.
 
I think the reason new builds have the grid switch arrangement is to comply with Part M. Do you have to with your refurbishment? I think either arrangement, 20 DP switches and socket under worktop or just socket under work top is okay. I agree with having the socket in an adjacent cupboard, if at all possible, especially with built in appliances. I would consider a kitchen/utility RFC or Radial as options.
Correct. It is change of use, so I must comply to all regs. of today. Treated as a new build.
Built in appliances MUST have an isolation switch, and apparently even if you have the function switch and plug above worktop, it still has to have and isol. switch. And these cannot be in the adjacent cupboard, must be instantly accessible "At times of peril".
The Utility room doesn't have built in appliances, and there are no cupboards. So all plugs will be hidden, with appropriately located / labeled individual isolation switches. Grid or individual, they cannot be in a cupboard - which makes perfect sense to me. In the utility, isolation switches not needed for part M or any regs, but for the sake of a switch and a bit of cable x 4, why not. Overkill is better in this case IMO. That's why I'm having so many circuits downstairs, each with own RCD in CU. I have the space to work in etc.
My basic wiring plan is : -
1 radial for boiler (Biomass, wood pellet burner type) which will also feed the boilers electric valves etc. in the loft. Not thought this one through yet, might put the loft stuff on upstairs ring. Awaiting boiler fitter/seller to visit site.
1 radial for immersion heater
1 radial for shower (or 2 if 2 showers)
1 ring for utility.
1 ring for cooker / hob / fan.
1 ring for remainder of downstairs, including the "Above worktop" kitchen sockets.
1 ring for a single outside socket (Which in future years I will expand to a shed)
1 radial for the smoke / heat / burglar system
1 ring for upstairs
1 downstairs lighting radial (But question.....by the time I have looped around the downstairs I am 2 or 3 metres from the CU.....may as well carry on and make a ring? Total run-out of radial is approx. 50 metres. 60 upstairs.
1 upstairs lighting radial, including loft lights. Same question as above.
11 RCD CU needed, so may as well get a 15 or even a 20 if the price is right.
Apparently, I also have to have isolation switches for the two lighting circuits. Preferably in the hallway........so it will be like 1 metre from the CU, but the CU is not to be used as an isolation fallback.
I'm gonna be a busy boy! A lot of chasing out.

As for the plugs being taken off. Whenever I have bought an electrical "Thing", if it had one of those moulded plugs I have always snipped that off and put a real one on. Since the 70's when those moulded things came out. Never had a warranty issue. Mind, probably only ever taken 3 or 4 things back.
 
You have some very odd ideas which you are stating as though they were fact. My thoughts:

Built in appliances MUST have an isolation switch, and apparently even if you have the function switch and plug above worktop, it still has to have and isol. switch.
A plug and socket is fine as a means of isolation.

And these cannot be in the adjacent cupboard, must be instantly accessible "At times of peril".
Nothing wrong with an appliance socket in a cupboard.

Grid or individual, they cannot be in a cupboard
Really?

1 radial for boiler (Biomass, wood pellet burner type) which will also feed the boilers electric valves etc. in the loft. Not thought this one through yet, might put the loft stuff on upstairs ring.
The boiler and its controls should normally be on the same supply.

1 ring for cooker / hob / fan.
Put the fan on the socket circuit via a socket or fused connection unit.

1 ring for a single outside socket (Which in future years I will expand to a shed)
Why on earth would you run a ring circuit to a single accessory?

1 downstairs lighting radial (But question.....by the time I have looped around the downstairs I am 2 or 3 metres from the CU.....may as well carry on and make a ring?
Don't complicate things by making rings where they're not required and not expected.

Apparently, I also have to have isolation switches for the two lighting circuits.
Eh? Why?
 
You have some very odd ideas which you are stating as though they were fact. My thoughts:


A plug and socket is fine as a means of isolation.
Not my usual sparky, but I had another one around to my present house to estimate a smoke alarm system. Over a brew he told me all these additional facts. The plug and socket as an isolation means must be (Obviously) above worktop and clearly labeled. But function switches / sockets aren't labelled.

Nothing wrong with an appliance socket in a cupboard.
If it is the isolation switch, it is wrong. Can't be shifting the cornflakes to find it.

Really?
Yep. The isolation switches have to be clearly visible and accessible.


The boiler and its controls should normally be on the same supply.
I thought so.

Put the fan on the socket circuit via a socket or fused connection unit.
Because? Does it not make sense to have the three cooking items on their own circuit?

Why on earth would you run a ring circuit to a single accessory?
Because it will be expanded to serve outside sheds etc.


Don't complicate things by making rings where they're not required and not expected.
Is it never expected to have lighting as a ring? Certainly not needed for safety anymore, as all the bulbs are 20w maximum.

Eh? Why?
So that visitors (Including fireman, mo-in-law) to the house can clearly isolate.
 
Last edited by a moderator:
You have some very odd ideas which you are stating as though they were fact. My thoughts:


A plug and socket is fine as a means of isolation.
Not my usual sparky, but I had another one around to my present house to estimate a smoke alarm system. Over a brew he told me all these additional facts. The plug and socket as an isolation means must be (Obviously) above worktop and clearly labeled. But function switches / sockets aren't labelled.

Nothing wrong with an appliance socket in a cupboard.
If it is the isolation switch, it is wrong. Can't be shifting the cornflakes to find it.

Really?
Yep. The isolation switches have to be clearly visible and accessible.


The boiler and its controls should normally be on the same supply.
I thought so.

Put the fan on the socket circuit via a socket or fused connection unit.
Because? Does it not make sense to have the three cooking items on their own circuit?

Why on earth would you run a ring circuit to a single accessory?
Because it will be expanded to serve outside sheds etc.


Don't complicate things by making rings where they're not required and not expected.
Is it never expected to have lighting as a ring? Certainly not needed for safety anymore, as all the bulbs are 20w maximum.

Eh? Why?
So that visitors (Including fireman, mo-in-law) to the house can clearly isolate.
 
[HandySparks, post: 1221399, member: 39513"]You have some very odd ideas which you are stating as though they were fact. My thoughts:


A plug and socket is fine as a means of isolation.
Not my usual sparky, but I had another one around to my present house to estimate a smoke alarm system. Over a brew he told me all these additional facts. The plug and socket as an isolation means must be (Obviously) above worktop and clearly labeled. But function switches / sockets aren't labelled.

Nothing wrong with an appliance socket in a cupboard.
If it is the isolation switch, it is wrong. Can't be shifting the cornflakes to find it.

Really?
Yep. The isolation switches have to be clearly visible and accessible.


The boiler and its controls should normally be on the same supply.
I thought so.

Put the fan on the socket circuit via a socket or fused connection unit.
Because? Does it not make sense to have the three cooking items on their own circuit?

Why on earth would you run a ring circuit to a single accessory?
Because it will be expanded to serve outside sheds etc.


Don't complicate things by making rings where they're not required and not expected.
Is it never expected to have lighting as a ring? Certainly not needed for safety anymore, as all the bulbs are 20w maximum.

Eh? Why?
So that visitors (Including fireman, mo-in-law) to the house can clearly isolate.
 
I think you might have to repost that. It's probably the shock of Trump being made President, but I haven't got the foggiest what you are saying above?
 
HandySparks asked a heap of questions, which I couldn't answer individually. So I copy/pasted the lot, with my answers. See his Q further up the thread.
 

Reply to The age old Grid switch topic in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

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