Can I switch 3 lighting circuits using 1 switch with only 1 live feed

[telectrix]

Expensive generally? Or expensive as compared to another solution? If so, what is specifically the expensive bit? Thx

3 unnecessay MCBs.

 

[DrJarmin]

If one circuit has a fault only that particular circuit will remain tripped - allowing quicker trouble shooting and the remaining 2 circuits to keep working. Well, that was the plan at least. Could it be achieved without the 3 MCBs?

3 unnecessay MCBs.

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Hi westward10 - this is the crux of the issue.

I have one switch in my house and want to split the existing light circuit of ~30 lights into 3 circuits of 10 lights each. At the moment water ingress causes one of the 30 lights to stop all lights working. I don't have an easy option to add more switches indoors as there is no route to put in the additional cable without a lot of work.

Why are the outgoing lines from the three mcbs linked together.

 

[westward10]

Where are the three mcbs in relation to the three gang switch.

 

[DrJarmin]

Where are the three mcbs in relation to the three gang switch.

Do you mean the switch in the diagram ? That switch is optional. Would just allow individual switching of each strand of lights.

 

[Dartlec]

Hi pc1966

For the external junction boxes, previously used waterproof boxes with choccy block connectors inside to run each light and continue the run and then fill the box with nearly a whole tube of silicon to stop water ingress. Of course this means no changes are possible. Is there a better way to do it?

In theory a properly made waterproof box is all you need, but in practise water gets into most things eventually.

This stuff or similar is good for filling boxes, and you can remove and replace connectors in it, You can also buy Junction boxes that are pre-filled with it. If the boxes are being buried or hidden then suitable Wago or similar connectors would be better than choccy block.