Hi,
I am sure this was asked before but couldn't find anything on search. So there we go.
Can you make a OR light bulb circuit with two SPST? (I am sure it can be done, the question is more, would it pass the code?)
What I mean by this is that I want to have two SPST and connect hot together and neutral together so that, only one of them needs to be on to light the light bulb. Using two SPDT would make AND circuit, but what I need is OR circuit.
The variation of this would be, 1 SPST + relay from the garage door opener light bulb. Basically I want to be able to turn the light on either -manually with the switch, or when the garage door opener relay is closed.
That's what I was really looking for. So I guess the problem is increased current carrying capacity. I guess the solution is to put another relay... probably not worth the money for this application.
Defective premise. You CANNOT make a true Or circuit with two SPST switches. You can only make an And circuit, or you man make a "half duplex" Or circuit, in that if the light is Off, then either switch can turn it On and Off from ONLY that switch, and only as long as the other switch is left alone. But if you turn it on with A, you CANNOT turn if Off with B, and vice versa. A true Or circuit would require that. This is what 3way switches provide.
I don't see why you cannot make OR circuit with two parralel SPST switches. In fact, I think it's quite obvious. You turn either or both of them on, the light turns on. There we go.
But if you turn it on with A, you CANNOT turn if Off with B, and vice versa.
Well I guess after doing this electrical thing for 30 years I've seen a lot. And a light wired the way you asked would not be wanted. I see both switches closed and someone standing next to one flipping it on and off with no results. Then leaving it like they found it and going to the other one with the same result. But hey, that's just my imagination running wild.
I just realized you're an engineer, now I understand.
Well I guess after doing this electrical thing for 30 years I've seen a lot. And a light wired the way you asked would not be wanted. I see both switches closed and someone standing next to one flipping it on and off with no results. Then leaving it like they found it and going to the other one with the same result. But hey, that's just my imagination running wild.
I just realized you're an engineer, now I understand.
I'd like to say politely, but, whether wanted or not by the mass is not your problem really. Also I know how to wire SPDT safely and as per code. Thank you very much. Doesn't take lots of skill really. And stop talking about people flipping switches and expecting anything. I gave a good example. Did you read it?
The garage door opener lamp turns on when remote activates door and lamp stays on until it times out. Most openers have a lamp switch to manually override and turn lamp on and off. However they each control the lamp separately
Well.. I would apprecite any real answers, other than complaining that no one ever wanted it and no one has ever done it. Any competent electrician to take the challenge? (Or do you tell your client "no one has ever done it or wanted it so your needs are ignored.")
And really going back to the original question... (and forgetting if anyone else "needs" this kind of circuit) would really be the only way to solve the "example" I have given (let's make it simple, one switch, one garage opener, one light bulb)? Any original thoughts to solve this cost-effectively?
Ok. this is waste of time. How more specific does it have to be? (Did you really read my original post?) One light switch, one garage door opener, and both will control one light bulb with OR logic. I don't think it will get any more specific than that.
Genie garage door opener buttons have a switch for a light built in, so if you want it 2 switches, just add another garage door button. Easy, and all low voltage, simple wiring.
My threads were erroneously erased. Wire up switch directly to lamp wiring and use the same source (leg), as you will be paralleling when manual override switch is turned on.
Well.. I would apprecite any real answers, other than complaining that no one ever wanted it and no one has ever done it. Any competent electrician to take the challenge? (Or do you tell your client "no one has ever done it or wanted it so your needs are ignored.")
My "clients" aren't so cheap that they want to only light their garage with the opener light. Also most wall controls already do this, which has been pointed out many times. Plus you have a bad attitude.
I don't see why you cannot make OR circuit with two parralel SPST switches. In fact, I think it's quite obvious. You turn either or both of them on, the light turns on. There we go.
This is a simple boolian math logic equation and ignoring half of an equation does not make your solution valid
That's not a full Or circuit, because the light can only be turned off as an And circuit. A light has two states, On and Off, you are only describing the first half of the problem solution, turning the light On.
3 way is the only way. Any thing less would be uncivilized.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Electrician Talk
2.3M posts
93.1K members
Since 2007
A forum community dedicated to professional electricians, contractors, and apprentices for residential and commercial work. Come join the discussion about trade knowledge, tools, certifications, wiring, builds, scales, reviews, accessories, classifieds, and more!