50W 12V Downlights

[EdwardPeck]

I am fitting downlights in our living room. The guides say 1.5m sq per 50W light. This will mean we need 20 downlights. I was hoping to daisy chain from the existing rose light (which we will be removing). What is the limit I can fit, and how do I work out what that limit is?

 

[dingbat]

1.5 metres square is 2.25 square metres. Check your calculations.

 

[Lectrician]

How many other lights do you have on this circuit, and how many new ones do you want to add?

a 5amp fuse, at 230v can supply a maximum of 1150watts
a 6amp MCB, at 230v can supply a maximum of 1380watts

You should allow 100watts per pendent.

You can apply diversity - not all lights are likely to be on at once (or are they?)

 

[EdwardPeck]

We have 600W at present. But as you say we never have them on at the same time.

Presumably I don't then add the low voltage bulbs each at 50Ws. Or do I?

 

[RF Lighting]

Presumably I don't then add the low voltage bulbs each at 50Ws. Or do I?

Yep.


1kW of lighting in your living room

Are you sure you've done your sums right?

 

[EdwardPeck]

No I havent. Ding Bat was right. So I'm about 50% out. So 10 lights not twenty.

So 500W. Still a lot!

 

[securespark]

Diversity from memory is 66% on dom lighting....

 

[RF Lighting]

Diversity from memory is 66% on dom lighting....

Not a bad memory for an old fellar

 

[securespark]

Sorry? I've forgotten what we were talking about...

 

[plugwash]

imo diversity on lighting cuircuits MUST take into account what the installation is like. If each room has only one lighting setup then i would expect all lights to be on at the same time on a fairly regular basis, if on the other hand each room has multiple setups then the chances of every room having every light on may be pretty low depending on the users of the installation.