Adding a switch to a motion sensor lantern

[Hedgehog1]

Hello!

I’ve recently removed an old motion sensor security light and I’m in the process of replacing it with a B&Q motion sensor lantern. I’m making the replacement for aesthetic reasons.

The lantern I have bought is this one:

http://www.diy.com/diy/jsp/bq/nav/n...refview=search&ts=1191588183702&isSearch=true

The old security light had no switch. It used a surface run 1.5mm2 twin and earth cable running directly from the CU. The instructions with the new lantern state that the connection should be via a wall switch for ease of operation.

The cable (and soon to be fitted switch) are hidden behind a cupboard in the vestibule. The CU is located in the cupboard too. I’m going to use the existing cable that was used for the old security light. As it's hidden, I wont be cutting a chase in the wall. I also wish to use a surface mounted switch. I note from page 349 of Collins Complete DIY Manual that the work is notifiable. As for mounting the light switch it states:

“Screw a plastic or metal mounting box to the wall for the switch, and cut a chase in the plaster for the cable….”

I’ve bought a mounting box and switch from B&Q too. The box is labelled “Pattress 1 gang 16mm” and the switch is labelled “1 way 1 gang switch”. Both are white plastic and both have “Crabtree Electrical Excellence” on the wrappers.

My question (finally!) is that the thin plastic webs that cover the cable entry holes are at the back of the mounting box. I wish to surface run the cable. Do I need a particular mounting box, or is it acceptable to drill a small hole at the side of the box to allow the cable to enter?

I notice that B&Q do this (drill holes in the side of the mounting boxes) on the demo boards at my local store in Wigan.

Thanks!

 

[luminaire]

It's quite acceptable to enter the box from the side if you wish to do so.

However, light switches have a permanent live and switched-live in order to do the switching. In other words no neutral.

Now if you are bringing the supply direct from the CU, then you cannot use an ordinary light switch for the live and neutral.

What you must do is use a 3A switched FCU. The feed side will be from the CU, and the load will be from the lamp.

 

[Steve]

If the supply is fused at 5 or 6 amps, then you CAN use a normal lightswitch as you have.

Wire the incoming live to the COM, and the outgoing live to the L1.

Wire the 2 neutrals to a terminal block.
Wire the earths to an earth terminal, if available. If not use another piece of terminal block.

 

[Hedgehog1]

Hi,

Thanks both for those useful replies. I'll drill a small hole at the side of the mounting box to allow the cable to enter.

Cheers!