Multiple circuits in an accessory

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Mr Sworld

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Hi guys.

Is it considered acceptable in domestic work to have a triple lighting switch that has feeds from two, separate, circuits? Industrial/commercial has this all the time in the large multi-way grid system lighting plates due to balancing lighting across fuses or phases.

I'm looking at the idea of one switch on the plate controlling a kitchen light and the other two controlling outside lighting. Obviously the kitchen light is off the ground-floor lighting circuit but the outside lights will be fed from a sub-main CU.

Now I'll know there will be more than one trip to lock off but, as this is uncommon in domestic work, others may not. Labelling the switch will overcome this but will look untidy...... Your ruminations please. :)

 

Flying Scotsman

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NO i would say unless its clearly marked then no its not considered acceptable

 

Mr Sworld

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Hmmmm...

I've just found the reg, 514-11-01, A durable warning notice must be permanently fixed in a clearly visible position to identify the appropriate isolating devices, where equipment or an enclosure contains live parts which cannot be isolated by a single device.

Oh well, it'll have to be two separate switch plates then!

 

Mr Sworld

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it would be acceptable if there is one main isolator that will turn off all circuits,ie, do both circuits come from the same main switch, is there a main switch at the incomer?
Yes they both come from the same CU but who would turn off an entire installation to work on a light switch. I think I will go down the road of separate plates, it's safer overall and means that it's more obvious as too which switch controls what.

Fed the old horse it oats yet this morning Steps? (Make what you will of that! ]:) )

 
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As long as the MCB's are suitably labelled...

and if considered neccesary to avoid confusion you have provided a suitable

Chart, Diagram, table or equivalent form of information.

Can't see any problem whatsoever.

reg 514-09-01 (iii) covers your back.

Any person, doing any work should identify the relevent issolation points before opening covers etc..

As long as you have provided the information... whats the prob????

I cannot see this is any worse than the ole landing light switch..

which can be wired to strappers in the downstairs double gang switch also working the hall light...

(upstairs & downstairs circuits both in double gang switch!)

[we could drift back to borrowed neutral here i not carefull:| :eek: ]

which is worse two circuits in a switch...

or a physical upstairs light on downstairs circuit?????? :)

Whichever you preferences put a good clear label on the fusebox!!!

Or even stick another caution label inside the switch

e.g. "Fuses 5 & 8 supply these switches"

so when someone opens it up they could see what to isolate???

 

Mr Sworld

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I have considered producing a 'house manual' for the property listing all the service points, electrical layout and copies of manuals for fixed items, etc, etc. It would solve many problems for whoever we sell it to in the future.

I'm going to have to have a good think about this one. One single switch plate will look a lot neater but the back box is going to start to get crowded with the amount of wiring that will have to go in there.

Hmmmm... decisions, decisions!

 
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I have considered producing a 'house manual' for the property listing all the service points, electrical layout and copies of manuals for fixed items, etc, etc. It would solve many problems for whoever we sell it to in the future.I'm going to have to have a good think about this one. One single switch plate will look a lot neater but the back box is going to start to get crowded with the amount of wiring that will have to go in there.

Hmmmm... decisions, decisions!
With all my rewires I provide a few additional sheets with any special info for the customer..

e.g. as you point out, where is the natural isolation point for outside lights?

upstairs/downstairs/own circuit/spur off ring??? ?:|

all possible & valid... but need to be noted!

also I confirm any concealed routes to switches/sockets...

especially properties with part wood & part solid floors...

some sockets go up the wall others go down...

any standalone PIR sensors which bulbs they work,, (cuz sometimes it is not always obvious!) etc.. etc..

note it down when you do the job..

staple it to the cert...

write in the box on the certificate schedule of additional records something like 'three additional sheets with circuit distribution details'.

On any additional sheets reference them back to the serial No of cert and date of job, any job/contract ref etc..

keep a copy for youself...

and I would suggest that you can rest easy saying you have taken all reasonable measures possible to inform the user of the installtion.

Also! this info helps if you go back years later when they have changes done! :D

 
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the back box is going to start to get crowded with the amount of wiring that will have to go in there.

Just stick in a deeper back-box...

you could get one-heluva lot a wires in a 47mm box:^O:^O

 

steptoe

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most dwellings have this situation, upstairs lights and landing light and hall light scenario, no big issues there.!

like i say all the time, too much time spent on regs and not enough time in the real world.

 

steptoe

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As long as the MCB's are suitably labelled...and if considered neccesary to avoid confusion you have provided a suitable

Chart, Diagram, table or equivalent form of information.

Can't see any problem whatsoever.

reg 514-09-01 (iii) covers your back.

Any person, doing any work should identify the relevent issolation points before opening covers etc..

As long as you have provided the information... whats the prob????

I cannot see this is any worse than the ole landing light switch..

which can be wired to strappers in the downstairs double gang switch also working the hall light...

(upstairs & downstairs circuits both in double gang switch!)

[we could drift back to borrowed neutral here i not carefull:| :eek: ]

which is worse two circuits in a switch...

or a physical upstairs light on downstairs circuit?????? :)

Whichever you preferences put a good clear label on the fusebox!!!

Or even stick another caution label inside the switch

e.g. "Fuses 5 & 8 supply these switches"

so when someone opens it up they could see what to isolate???
sorry special, I see you already covered that issue. :8}:8}

 

steptoe

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Yes they both come from the same CU but who would turn off an entire installation to work on a light switch. I think I will go down the road of separate plates, it's safer overall and means that it's more obvious as too which switch controls what.Fed the old horse it oats yet this morning Steps? (Make what you will of that! ]:) )
you do realise Mr Sworld, that most MCBs (SP)do not count as isolators in this aspect of the regs,

ie, it will not turn of all LIVE conductors.

ignore the regs or work to them faithfully!

or else just do the sensible thing.

why do people ask such questions when they already know what they want to do anyway?

 

Mr Sworld

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you do realise Mr Sworld, that most MCBs (SP)do not count as isolators in this aspect of the regs, ie, it will not turn of all LIVE conductors.

ignore the regs or work to them faithfully!

or else just do the sensible thing.

why do people ask such questions when they already know what they want to do anyway?
I was only asking........ :(

 

steptoe

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now now mr sworlds, its OK.

but TBH in a single phase installation, in a private dwelling, to put two lighting supplies inside a single box I personally dont see any problem.

maybe its just the way I do things sometimes.

after all if diy bob wants to do someting then he SHOULD isolate all possible supplies,

ie, the WHOLE house.

and if its a spark, well he should know better and to check all possibilities,

re: the borrowed N thread.

 
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evenin all :)

"after all if diy bob wants to do someting then he SHOULD isolate all possible supplies,

ie, the WHOLE house."

From my experience a lot of joe publics DO actually turn off the main switch, no mater what they are doin!

The number of times i've been on a job working on a socket and

because the lights are still on...

the customer says..

"dont you need to turn the power off?"

and you explain that the circuit is OFF.. Just the sockets.

or vice-versa...

they assume if one bit of electricity is on it is ALL on!!! :| :|

 
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