I have three lights in a room.
A and B are on one circuit, and switched from two locations.
C is on another circuit and also switched from two locations.
I would like to change the switching arrangement so that B comes on when either A or C is on. Is there an easy way to do this?
Simplest way would use a relay ...
Make that two relays ...
F scribbled...
Answer either -
A - the electrician is Polish
B - the train arrives 10 minutes early
C - use a 3 amp fuse
1 is more reliable
NT
Two double pole switches are even more reliable.
Wouldn't that require a relay with two coils?
Where can you buy a normal looking double pole changeover switch?
A relay?
Brian
If you do the logic with diodes, its cheaper & more robust. 1kV 1N4007s are cheap as chips.
NT
diode logic become a bit complex with ac.
But then you've got to have low voltage DC available for the switches, rather than keeping coils/contacts all on mains.
Why would you do that?
NT
To try and keep it more understandable for anyone encountering it in future ...
This is becoming a maze of misunderstandings. I see no reason to convert anywhere to low voltage dc, and don't know why you'd consider so doing.
NT
On Thursday 05 December 2013 20:53 snipped-for-privacy@care2.com wrote in uk.d-i-y:
Because someone said "diode" and diode logic only works with DC,
You can do it with one.
I program it in my home automation software, which all the light switches are connected to anyway. If there's been no one in the room for 20 minutes, it switches 2 of them off.
Not at all. Take the 2 switched lives, put each through a diode, pass that output to one side of the relay coil, with the other side to neutral. Voila, diode logic on ac.
NT
Providing you don't mind a pulsating half wave output it will work on AC as well.
Colin Bignell
relays clattering?
I was thinking of using a filament lamp and feeding it from both switches through mains rated diodes. Light output will be reduced, but simple and no moving parts.
Colin Bignell
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