Mains lighting using a reed switch

[rustynails]

Got asked a question the other day whether it would be safe to use a reed switch to operate a light. The customer asked me whether I could put a light in a cupboard and make it automatic by using surface contacts as the switch. I did'nt know and said that I would think about the idea.

I'm opening it up to get some ideas from you guys as to whether you think it would be installable. I've heard that low voltage maybe a safer option, but would like to know whether or not it would work with standard 1.5mm. I drew a little diagram as to what I thought the wiring might look like, apologies for the kiddyness of the drawing...


Any thoughts?

 

[telectrix]

absolutely no way can you supply 240V to a reed switch. they are only rated for elv. i'e. 12V.

 

[IzzyS]

You need something like this. Or a PIR. Cupboard door light switch / wardrobe lighting switch

 

[kingeri]

Could use 230v if you wanted to adapt it to a booby trap.

 

[KAS1]

Perfect

You need something like this. Or a PIR. Cupboard door light switch / wardrobe lighting switch

 

[rustynails]

You need something like this. Or a PIR. Cupboard door light switch / wardrobe lighting switch

Ideal solution.

 

[ayjay]

if its an alarm type reed switch they,re normally closed? so the light would come on when u closed the door and vice versa
i thought of using one on my citreon 2cv to operate the interior light when i opened the door, but couldnt for the above reason
a pir is good though

 

[tazz]

reed switches are rated at 0.2 amps @5v-12v, you can either make a small low votage alarm circuit and switch a mains rated relay....or easily use a mains lighting pir...!

 

[Adam W]

If it has to be a reed switch you could either switch the ELV and have the transformer running constantly, use a relay to switch 230v, or just use a cupboard switch like most people do.