Lighting Circuits

R

ryanj

Okay, I've decided to rewire my rather unsafe lighting circuit.

I live in a bungalow with a loft conversion, and there is quite a lot of lighting, it is currently unevenly spread out over two fuses.

Here is a simple floor plan of my house,

floorplan.jpg


A red dot indicates a lighting fixture, the dot to the left of the house is a 500watt securety light.

My problem however, is how many circuits I should use to spread the lighting over, should I:

  • Put all the lighting on one 6amp circuit breaker
  • Spread the lighting evenly over 2 6amp circuit breakers (perhaps left house and right house?
  • Something else? :)

Thanks in advance. :)
 
Sponsored Links
What size cable do you intend using.
I would use 1.5sq T&E as opposed to 1.0sq and use a 10A MCB.
One circuit should suffice.

Although I personally, would connect the 500W spot light to a separate 6A MCB. (is this light fed from a switch that also supplies other lights?, if so, all lights fed from here should be on the same breaker for safety reasons)

I know I'm exceeding my brief a little here, but I’ll say it anyway.
I HATE those 500W spotlights especially the one’s with built in sensor! :) Did you ever consider fitting a 70W SON floodlight instead? These are much more effective as security lighting in my opinion and are not expensive to run. I have one at the rear of my house controlled by photocell, leaving it totally automatic; it switches on at dusk and off at dawn. The light output of these is an amber colour (don’t try and compare it to a 70W bulb! The output is much greater.)
 
ok 18 lights excludeing the outdoor light

where is the fuse box? in the cupboard?


you should avoid putting switches on different cuircuits in a box together

i'd advise going for 3 6A breakers all in 1.5mm cable

1 for the left of the house
1 for the right of the house
1 for the floodlight and anything on the same switchplate as it
 
and i'd put the floodlight one on the rcd side of the CU
 
Sponsored Links
i disagree plugwash, why 6A breakers? RCD protection is really not required here and i would advise against it for SON floodlights (if you were to use one) as it may be subject to nusance tripping. As regards not haveing separate circuits entering the same box I made this point already.
 
a 10A breaker should have 10A switches iirc

and not all light fittings are suitable for conencting to a 10A lighting cuircuit (ses and sbc lights 5A sockets for lamps controlled by lightswitches etc)
 
Plugwash, my fusebox is contained inside the pantry on that diagram.

BR, the floodlight was here when we moved into the house. I wouldn't have picked it! :)

Thanks for the advice, keep it coming! :)

And I forgot to mention the other two lighting points in my attic. :oops:
 
I would go for two 6A circ's - some people advocate wiring the circuits so that wherever you are in the house, if one circuit goes, there will always be a light on the other nearby so you can see your way around. This is up to you, though.

The sec light I would wire off the ring via an FCU.

Ditto the loft - I guess there is (ring) power in the loft
 
Yep, there is a ring circuit in the loft.

I like the idea of having a nearby light on - but is it allowed to run more than one circuit inside a single piece of conduit - otherwise it'd be very hard to run.
 
plugwash said:
a 10A breaker should have 10A switches iirc
Ah - just like all switches (FCUs, Sockets etc) on a ring main have to be rated at 32A? That makes sense.

and not all light fittings are suitable for conencting to a 10A lighting cuircuit (ses and sbc lights 5A sockets for lamps controlled by lightswitches etc)
That of course is very true. Thank heavens then that BS1363 socket outlets are all rated at 32A, and that nobody makes any dimmer switches rated at less than 1.38kW for use on 6A lighting circuits, otherwise think of the danger we'd be in!
 
i'm just repeating what other sparks have told me

imo the 5A socket issue is particularly important as you don't know what some idiot will plug into it

anyway lighting load in general seem to be on the increase so useing 2 cuircuits gives you the ability to uprate the breakers later as long as you choose your switches right

and yes i consider that facts that double sockets aren't rated at full load each side and that socket doublers generally aren't fused to be seriously bad system design
 
plugwash said:
i'm just repeating what other sparks have told me
What does The Book say?

imo the 5A socket issue is particularly important as you don't know what some idiot will plug into it
True.

anyway lighting load in general seem to be on the increase so useing 2 cuircuits gives you the ability to uprate the breakers later as long as you choose your switches right
I agree about the multiple circuits. (a) so that a trip doesn't take out the whole house. (b) because ryanj already has too much for a single 6A anyway. Still think you're wrong about the switches though - surely they only need to be rated for the load they will switch, not for the load on the entire circuit? You can get plates for grid systems with at least 24 positions, which would mean, if you're right, that even 10A switches wouldn't do. I'm not convinced...

and yes i consider that facts that double sockets aren't rated at full load each side and that socket doublers generally aren't fused to be seriously bad system design
Yo. But even if they were rated at 26A, that wouldn't help. And what about single sockets, which by your argument should be rated at 32A?
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top