Hi can some please help me, I have 2 x20w halogen mini down lights mounted in a wall type cabinet, they are wired into a 12v transformer and plug into a wall socket. The problem is every time you want the lights on to the cabinet, you have to keep plugging them in to the wall socket. I want to leave them plugged in permanently, and need to wire in a small light switch, How do I do that, and what side of the transformer should the switch be wired, can some one show me a diagram of where and how to wire in this switch. I have purchased a small slimline switch
A few different ways of doing this depending on what circuits are close by,
You could take a direct feed from your lighting circuit or a Fused Spur from your power circuit, you could even add a new circuit from the CU if close by, the switch you intend to use should be installed before the transformer. If you add a new circuit it will have comply to part p of building regs.(see part P in projects): http://www.diydoctor.org.uk/projects/partp.htm and is notifiable work. Any addition or new circuits should be inspected and tested and be certified to comply to BS7671 and assure the installation is safe is to use.