Overloading a lighting circuit

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Hi all,

we are upgrading the lighting in our kitchen, at the moment it has 6 40w(downlighters) which are far too dim (like me)
so I thought I had better check on how many lights I could have on a circuit.

The breaker is 6a for the whole house 7 rooms + bathroom.

the loft bed room has 6 downlighters (40w?)
bedroom 1 1 x 60w
bedroom2 1 x 60w
sitting room 3 x 60w
landing 1 x 60w
hall 2 x 60w
living room 1 x 60w
downstairs 1 x 60w + 1 x 40w downlighter
Dining room 6 x 40w

=940w which seems well in the 1380w for a 6a breaker.

Presuming the switch can cope with the load (its a lightwave rf remote dimmer rated at 3000w) then would there be a problem changing the 6 kitchen downlighters (240w) to say 10 60w bulbs ?

This give a total of 1300w.

to me it seems fairly obvious its ok but always best to check.

Many thanks
 
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.... The breaker is 6a for the whole house 7 rooms + bathroom. .... =940w which seems well in the 1380w for a 6a breaker. .... Presuming the switch can cope with the load (its a lightwave rf remote dimmer rated at 3000w) then would there be a problem changing the 6 kitchen downlighters (240w) to say 10 60w bulbs ? ... This give a total of 1300w. ... to me it seems fairly obvious its ok but always best to check.
By my arithmetic, your present total load in 1360W (10 x 60W + 19 x 40W) which, by the skin of it's teeth, is within the 1380W theoretical maximum for a 6A breaker, but that would rise to 1760W if you made the change you are suggesting, which is way over the limit for a 6A breaker. In practice, you are virtually never going to have all lights on simultaneously, but one should not really have a circuit in which that is a theoretical possibility and, if it happened, would result in the circuit being overloaded.

One thing you could discuss with an electrician would be the possibility of upgrading the breaker to 10A, since the cable of the circuit would almost certainly be adequate for that.

However, much more to the point is that 1360W, let alone 1760W, of lighting in a 3-bed house is an awful lot in this day and age, and must be costing you a fortune to run, so you really should be thinking about changing at least some to LEDs (or maybe CFLs) and/or some more efficient means of lighting (particularly where you currently have downlights) Your proposed 600W for your kitchen (and even the present 240W, and the 240W in your loft room and dining room) is an awful lot (some would say 'a ridiculous amount') for one room, which could probably be lit adequately with a tiny fraction of that power using LEDs or CFLs.

To put this into perspective, in my youth almost all rooms were lit with a single 60W or 100W pendant lights (which could probably be achieved by a 12W -18W LED today), sometimes even 40W in bedrooms, and I don't recall us having to fumble around in very dimly lit rooms!

Kind Regards, John
 
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I would agree seems to be rather a lot of power used for lighting, I will put against your list what I have in my house to give some comparison.

the loft bed room has 6 downlighters (40w?) My loft with no bedroom 58W fluorescent
bedroom 1 1 x 60w My master bedroom 11W CFL + 4 x 4W GU10 LED
bedroom 2 1 x 60w Mine 11 CFL and 18W 2D lamp bit OTT to be frank.
bedroom 3 Mine 1 x 11W CFL
landing 1 x 60w Mine 18W fluorescent battery backed.
living room 1 x 60w Mine 10 x 5W LED
hall 2 x 60w Mine 2 x 40W
downstairs 1 x 60w + 1 x 40w downlighter
Bathroom mine 4 x 4W MR16 LED replacements plus 11W CFL
Dining room 6 x 40w Mine 6 x 5W LED candle
Kitchen 6 x 40W Mine 1 x 70W fluorescent + 1 x 28W LED fluorescent replacement.
Your total = 1220W = 5.3A My total = 428W = 1.8A

Spot lamps can work well reflecting light of white or light surfaces, however the downlight shining on a dark floor need to have a reasonable area to work, 6 inch round x 6 would be good, even 4 inch reasonable however 2 inch is simply not enough area even if you get the lumen my kitchen has 8000 lumen approx it was more until the 58W fluorescent was changed to 28W LED. So I would say direct lighting where not bounced off a white surface 3W is about the limit for a 2 inch spot lamp, so around 250 lumen per lamp, so you will need around 30 down lighters so around 90W total.

With so many always thought it would be fun to arrange to emulate the great bear or some other star cluster it would looks like a planetarium so why not go the whole hog? Some thing like this
round-24w-led-surface-panel.jpg
which is 12 inches across 24W and 1900 lumen would be far better at lighting, maybe a bit too big to have 6 you can get larger units which let into the ceiling
Elegant-Surface-Mount-Led-Lights-Ceiling-73-For-Your-Small-Ceiling-Fans-with-Surface-Mount-Led-Lights-Ceiling.jpg
Not sure I would want such large holes, think I would go for surface mount, mothers kitchen uses the old 2D fluorescent fitting, looks better than the long tube fluorescent think hers is 28W which is a little low without the under counter and hob extractor lights.
 
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Thanks for the replies chaps.
Although it is a 3 bedroom house it is very large (4 levels).
The reason we don't have any LED is that the Lightwave system we have doesn't work very well with them.

Actually looking at it in the cold light of the day (geddit) I have the following

Loft bedroom 6 x 20w
Main bedroom 1 x 60w
2nd bedroom 1 x 60w
upper landing 1 x 60w
bathroom 2 x 60w
3 x 28w
hallway 2 x 60w
living room 1 x 60w
sitting room 3 x 40w
lower landing 1 x 20w
1 x 60w
Dining room 6 x 20w
kitchen 6 x 20w

this is 1124w

To be honest 80% of the time the loft room and 2nd bedroom aren't even occupied.
the upper hall is rarely on and when it is most if not all the others are off.

Looking at the above I suspect that we would actually end up with 8 x 40w max. which would be an additional 200w total 1324w which is (JUST) in the limit.
If this is the case I think I would rather get a 10a fuse fitted to play safe.

many thanks
 
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would there be a problem changing the 6 kitchen downlighters (240w) to say 10 60w bulbs ?

This give a total of 1300w.

to me it seems fairly obvious its ok but always best to check.
Well, to me it seems fairly obvious that if you think you're going to need 10 lights to satisfactorily light up a room then those lights cannot be any good at the job of lighting up rooms. Probably because they are fundamentally and deliberately designed to be bad at it.


The reason we don't have any LED is that the Lightwave system we have doesn't work very well with them.
Then don't use it.

Simples.
 
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ban all shed
Nothing is ever that simple.
The kitchen to us is not just a food prep area, its where we have our fire, its where we sit, its also a very odd shape. We want direct lighting over the food prep area and the washing up area.
It has very low ceiling with beams so most modern lighting will look horrible. I would rather have 10 lights running dim than 4 clinically bright lights.
And as we have invested so much in the lightwave infrastructure not using it isn't going to happen lol.

But I do appreciate the response and all the help I have received
 
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So you've added toy features to your lighting system, and in doing so have removed very important functional capabilities.

lol
 
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If your place is split over four floors, are you sure all the lighting is on the one circuit breaker?

I would think it would be more likely to be split between 2 or 3 breakers; maybe ground floor on one 6A, first floor on another 6A and 2nd floor + attic on another 6A (substitute 5A rather than 6A if using fuses rather than MCBs...)

Not a sparks, so will leave it to those more knowledgeable to correct me if I'm wrong...

Cheers,
Colin
 
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If your place is split over four floors, are you sure all the lighting is on the one circuit breaker? ... I would think it would be more likely to be split between 2 or 3 breakers
That would certainly be more common, if the place had been re-wired in recent times, but if it was last re-wired a few decades ago, a single lighting circuit would probably be quite probable. However, one has to assume that he is (sure), otherwise he would presumably not have explicitly written:
The breaker is 6a for the whole house 7 rooms + bathroom.

Kind Regards, John
 
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Well, to me it seems fairly obvious that if you think you're going to need 10 lights to satisfactorily light up a room then those lights cannot be any good at the job of lighting up rooms. Probably because they are fundamentally and deliberately designed to be bad at it.

Then don't use it.

Simples.
You have made similar comments many times previously and I could not agree with you more.

Since late in the previous century I have been horrified many times when walking into new or display homes to discover so many Watts being expended in poorly lighting a small areas.
The LED replacements for the Halogens previously involved are more efficient but I consider that it would be much better if users gave more consideration to the larger LED "luminaires" which are now available.
 

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