wiring up a garage lighting circuit

Currently my garage has one light powered through a 5A RCD, with one switch. I'd like to convert this to 4 x (2x 70W T8) 6ft lamps, operating off two switches at either end of the garage. I also need to wire up a seperate 2 x single 70W T8 for the attic part of the garage. Total wattage will be 700W. It's all wired presently with 1.0m twin and earth.

I've decided to connect up 2 x 2way2 gang switches to cover both circuits.

These are my questions please.

1) I'm assuming 1.00m twin and earth throughout will still support the total 700 wattage? Is this satisfactory?

2) Will I have to uprate the fuse in the RCD (I work it to be a max of about 3A?)

3) My main question is, since upstairs and downstairs circuits are controlled from different circuits can they both be connected through the same 5AMP fuse in the RCD?

4) and if so which is the best way to send a live to the second 2way switch, either through a totally seperate wire from the fuse or can I just connect the live across from one switch to the other ie jump?

Hope this all makes some sense, as you can tell I'm no electrician

confused regarding the 5amp RCD.
Do you have a separate, fuse box protecting the garage or is the circuit protected by a fuse/breaker, that is also protected by an RCD?

The lights can be looped in and switch cables dropped for them, a two way function can be made by using three core and earth as strappers between the two switches. //www.diynot.com/wiki/electrics:lighting:two_way_lighting
1.0 mm cable will be okay without upgrading the fuse rating.

Hi I'm okay in how to connect the two switch boxes together using 3 core + earth. My problem is how do I get a live to the second lighting circuit (shown in green on the photo)?

I have drawn in a "loop" connecting both Commons (red) together thinking this may be the way to get a live across, but I've also drawn a new 1.00mm cable running through the fuse box, would this get a live into the second circuit and which is best method? I'm not sure if the new cable from the RCD AND the red common wire loop are both necessary?

Sorry, little unclear as to your terminology when you say "The lights can be looped in and switch cables dropped for them".

Thanks again

Cooperm said:

Currently my garage has one light powered through a 5A RCD

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There's no RCD anywhere in the picture you've posted.

I'd like to convert this to 4 x (2x 70W T8 ) 6ft lamps

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560W of fluorescent lighting?

Is this going to be your garage?



Seriously - unless your garage is enormous that's far too much lighting.

Cooperm said:

My problem is how do I get a live to the second lighting circuit (shown in green on the photo)?

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Why do you want half the lights to be on a 2nd circuit? One will be ample.

I'm not sure if the new cable from the RCD AND the red common wire loop are both necessary?

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Not only is it unnecessary it's dangerous and illegal.

Sorry, little unclear as to your terminology when you say "The lights can be looped in and switch cables dropped for them".

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//www.diynot.com/wiki/electrics:lighting

I'm no electrician

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Perhaps you should get one?

okay so the Memera 200 is a British Modular 250v Circuit Protection System isn't it?

I have a larger than double garage. 4 double strip lights is not uncommon for a garage. two in each half??? Why is that overkill, seen it a million times.

"why do you want half the lights to be on a 2nd circuit? One will be ample"

How do you make 2 x single T8 70w half of 560W? Not in my book, it's 25%. Hope you don't wire up my house with those maths.

"Not only is it unnecessary it's dangerous and illegal. "

If you're quoting legalities then which is the legal option then, it's either one or the other I gave two options, I didn't say both

Interesting photo. Though I do woodwork not grow plants.

Cooperm said:

okay so the Memera 200 is a British Modular 250v Circuit Protection System isn't it?

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I didn't say that it wasn't, just that there's no RCD in it.

How are the sockets supplied?

I have a larger than double garage. 4 double strip lights is not uncommon for a garage. two in each half??? Why is that overkill, seen it a million times.

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It's your garage - if your experience is that you want that much then go for it.

How do you make 2 x single T8 70w half of 560W? Not in my book, it's 25%. Hope you don't wire up my house with those maths.

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Sorry for the lack of precision.

Why do you want some of the lights to be on a 2nd circuit? One will be ample.

If you're quoting legalities then which is the legal option then, it's either one or the other I gave two options, I didn't say both

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You did, actually:

Cooperm said:

I've also drawn a new 1.00mm cable running through the fuse box, would this get a live into the second circuit and which is best method? I'm not sure if the new cable from the RCD AND the red common wire loop are both necessary?

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I do woodwork.

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Make sure you get high frequency ballasts.