3-part 3-way Switch Circuit Design

[Terry]

How about this?

[trbo20]

Thank you, Mark and everyone else, for the in-depth exploration of my project. I think after reviewing the responses, I'll probably just go ahead and stick with three independent circuits; as diodes and relays are really above my level of comfort. If I put all three switches in one box, the person entering the room can just karate chop all three at the same time.

Cheers!

-Tom

[Mark Lloyd]

That's the way I'd do it. If you add a third relay, you need 2 more diodes connected to the nodes that come just after the master buttons.

[Mark Lloyd]

That'd work, although 3-way (SPDT) switches are TOGGLES. That is you have to see the light to know what flipping the switch will do. Also, using diodes simplifies control from multiple points (to add another control point, you just need more low-voltage wiring, and you don't have to rewire any existing switches).

[Bud--]

I don't think master-off can be done without relays (or X10).

Master-on can be easily done for all lights on a single circuit: [view with a fixed width font]

3-way switches H--+----------------+-----------------O | | Z x------- hot to zone 1 | +-----------------------O | | | +--O O--+ | M | | | | ON | +-----------------O | | Z x------- hot to zone 2 +-----------------------O | | OFF/MASTER | | | | more zones

M is the master switch (single pole switch) Z - add 4 way switches at this point for equivalent 3-way multiposition control

-- bud--

[Bud--]

Another trick that could be useful (but not particularly for this thread) - with a conventional 3-way, a single pole switch connected between the travelers is a master-on.

-- bud--

[Mark Lloyd]

I have seen one of those in a big library building. It made it easy to operate all the light switches at once.

Separate buttons do give you the advantage of not having to check all the lights just to make sure they're off.

[Harry]

It's even more terrible to LOSE.

[RBM]

That just shows it's still lost

[Terry]

I know we have already talked you out of using low voltage controls.

I am just posting a updated drawing once more since I have little to do and am trying to learn TinyCad.

[Mark Lloyd]

Looks good, except for one thing. With the diodes turned that way, you'd need a NEGATIVE power supply. The arrow on the diode symbol indicates conventional (positive to negative) current flow.