Controlling two lights separately with one switch

In summary: I have a single lighting switch at home which controls two sets of light separately, but I have no idea how it works.Here's what the single switch does when flipped on-and-off quickly,On -> Light A turns onOff -> A turns offOn -> Light B turns onOff -> B turns offOn -> Light A and B turns onOff -> A & B turn off...cycles repeat..Can anyone please tell me what device is making this switch function in such a special way? I have been puzzled over my switch for some time.Thanks.It looks like it is some kind of rotarbivitlum polf pilf.
  • #1
hobbes33
7
0
I have a single lighting switch at home which controls two sets of light separately, but I have no idea how it works.

Here's what the single switch does when flipped on-and-off quickly,
On -> Light A turns on
Off -> A turns off
On -> Light B turns on
Off -> B turns off
On -> Light A and B turns on
Off -> A & B turn off
...cycles repeat..

Can anyone please tell me what device is making this switch function in such a special way? I have been puzzled over my switch for some time. :confused:

Thanks.
 
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  • #2
hobbes33 said:
I have a single lighting switch at home which controls two sets of light separately, but I have no idea how it works.

Here's what the single switch does when flipped on-and-off quickly,
On -> Light A turns on
Off -> A turns off
On -> Light B turns on
Off -> B turns off
On -> Light A and B turns on
Off -> A & B turn off
...cycles repeat..

Can anyone please tell me what device is making this switch function in such a special way? I have been puzzled over my switch for some time. :confused:

Thanks.

Just sounds like a specialty mechanical latching switch. You could ask about it at the larger home improvement / hardware stores in the lighting section to see if they carry similar switches.
 
  • #3
Turn off the power and remove the switch from the wall and analyze it...

It may even have a name or model number on it.
 
  • #4
hobbes33 said:
I have a single lighting switch at home which controls two sets of light separately, but I have no idea how it works.

Here's what the single switch does when flipped on-and-off quickly,
On -> Light A turns on
Off -> A turns off
On -> Light B turns on
Off -> B turns off
On -> Light A and B turns on
Off -> A & B turn off
...cycles repeat..

Can anyone please tell me what device is making this switch function in such a special way? I have been puzzled over my switch for some time. :confused:

Thanks.

What physical type of switch is it? i.e. is it a simple up/down toggle, like a standard wall switch?


Anyway, the way the switch probably works is using a sort of cam - basically a wheel with three teeth, at 120 degrees (or possibly 6 teeth at 60 degrees). When you switch it on, the cam rotates 60 degrees, and closes a circuit to one light. Then you switch it off, the cam rotates another 60 degrees to an open circuit. Switch again, the cam rotates another 60 degrees, closing the circuit to the second light. Switch again, and it rotates 60 degrees, opening the circuit. Switch a third time and the cam rotates 60 degrees, closing a circuit to both lights. A final switch rotates it to an open circuit.

This is just a guess, off the top of my head. I've never seen a switch like this, but it would work.
 
  • #5
hobbes33 said:
Here's what the single switch does when flipped on-and-off quickly

Does it behave differently if operated slowly? If so, there might be some sort of pulse detector with a logic circuit. Just a thought.
 
  • #6
Sounds like a standard 3-way switch used in a non-standard configuration.

Common - Hot
Terminal A - Light 1
Terminal B - Light 2

When you flick the switch one way, it redirects the hot leg to one light (current returns via the neutral) and when you flick it the other way, it redirects the hot leg to the other light.

EDIT: Whoops, I just reread your post--it most definitely isn't a three-way switch.
 
  • #7
Sounds to me like it is hooked to some kind of stepping relay.
 
  • #8
Definitely magic.

Or DaveC's response...
 
  • #9
If you hear relay clicks, then it uses relays. Otherwise, it could work in lots of different ways! You're an engineer...pull that thing out and look at it!
 
  • #10
Sounds like a rotarbivitlum polf pilf.
 
  • #11
KingNothing said:
If you hear relay clicks, then it uses relays. Otherwise, it could work in lots of different ways! You're an engineer...pull that thing out and look at it!

Or better perhaps, find out what kind of thing it is and go buy one to look at. I have noticed that things I 'look at' (as in: take them apart) hardly ever work afterwards. If the light switch controls the lights in your room, you may not want to break the 'original' :)
 
  • #12
CompuChip said:
Or better perhaps, find out what kind of thing it is and go buy one to look at. I have noticed that things I 'look at' (as in: take them apart) hardly ever work afterwards. If the light switch controls the lights in your room, you may not want to break the 'original' :)
I'm going to guess that it is not sold anymore. I'm going to guess that it is also very rare.
 
  • #13
DaveC426913 said:
I'm going to guess that it is also very rare.

Why? I mean, I never heard of it, but doesn't anyone want that in their house?
Even if just for show / fun? :)
 
  • #14
DaveC426913 said:
What physical type of switch is it? i.e. is it a simple up/down toggle, like a standard wall switch?

It's a standard wall switch. It looks no different from other normal light switches in my house, just that this one had the special function. A guest would think that the switch only controls light A since he will have no idea how to operate this special switch and there's no clue to give it away.

KingNothing said:
If you hear relay clicks, then it uses relays. Otherwise, it could work in lots of different ways! You're an engineer...pull that thing out and look at it!
russ_watters said:
Turn off the power and remove the switch from the wall and analyze it...

It may even have a name or model number on it.

I've tried this, but the panel behind the switch is empty. So KingNothing, I wouldn't be able to hear the relays if they exist too.. The device seems to be above the ceiling and I can't spot any peculiar things from the "hatch" in the ceiling. :smile:


Anyway, i don't think it's a mechanical rotating switch or something like that, since I failed to mention another property of this switch, my bad. :biggrin: Here it is:
hobbes33 said:
Here's what the single switch does when flipped on-and-off quickly...
So here's what the switch when it is not flipped quickly.

Fast On -> Light A turns on
Fast Off -> A turns off
Fast On -> Light B turns on
Fast Off -> B turns off
*Pause for more than 1 to 2 seconds
On -> Light A turns on (instead of A & B turning on)
Fast Off -> A turns off
Fast On -> Light B turns on

So it seems that a pause of 2 seconds will cause the device to 'reset' to its original state.

It might be an electronic circuit together with some relays. But that answer would be too boring! Haha...
 
  • #15
hobbes33 said:
I've tried this, but the panel behind the switch is empty. So KingNothing, I wouldn't be able to hear the relays if they exist too.. The device seems to be above the ceiling and I can't spot any peculiar things from the "hatch" in the ceiling. :smile:
OK, that rules out a mechanical switch. It owsuld have been your finger providing the energy to toggle the states. Not so if the guts of the thing are in a remote location.
 
  • #16
Clocked flip-flops replicating a state machine! It's like a home improvement project for bored computer engineers.
 

1. How can I control two lights separately with one switch?

To control two lights separately with one switch, you will need to use a double-pole, single-throw (DPST) switch. This type of switch has four terminals, allowing you to connect two separate circuits to it. By wiring each light to a different circuit, you can control them separately with one switch.

2. Can I use a regular switch to control two lights separately?

No, a regular single-pole switch is not designed to control two separate circuits. It only has two terminals and can only turn one circuit on or off. You will need to use a DPST switch for this purpose.

3. How do I wire the two lights to a DPST switch?

You will need to connect the power source to one set of terminals on the DPST switch, and then wire each light to the other set of terminals. This will allow you to control each light separately, as each set of terminals will act as a separate circuit.

4. Can I use a dimmer switch to control two lights separately?

Yes, you can use a DPST dimmer switch to control two lights separately. This will allow you to not only turn the lights on and off separately, but also adjust the brightness of each light individually.

5. Is it safe to control two lights separately with one switch?

Yes, it is safe as long as you follow proper wiring and safety guidelines. Make sure to turn off the power before wiring the switch, and always use appropriate tools and equipment. If you are unsure, it is always best to consult a licensed electrician for assistance.

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