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Posted By: Bill Addiss Which Switch? - 11/21/00 12:57 PM
This is something that I heard recently from a Local Inspector that demonstrates good deductive reasoning, I don't know if he thought of it but I guess he could have, He's pretty sharp.

(purely hypothetical - not to code obviously)

If you have a Light in the Attic and 3 switches in the Basement (1 turns on that light) - How can you fgure out, by yourself, which switch it is and only make the trip up to the Attic 1 time?

The Attic is not within sight, no one else there [Linked Image]
Posted By: Vin Re: Which Switch? - 11/21/00 11:51 PM
Depending on the distance this might work.
Go to attic, attach a 9volt battery to hot and nuetral coming in from switch, now go downstairs and see what switch,in the off position gives you a voltage reading. You can also try wiring a recept. to the light temporarily and plugging in a radio with the volume on high and see which switch turns the radio on.
Posted By: Bill Addiss Re: Which Switch? - 11/22/00 12:24 AM
Vin,

Hint: It's not that complicated. Much easier - No rewiring or testing of anything.


I don't think I would try that 9 volt battery idea.
Posted By: Jeff T Re: Which Switch? - 11/24/00 03:13 AM
I would guess one is the basement light. Of the other two I would switch one on and leave the other off. If the attic light is on or off tells me which switch.

just a shot in the dark [Linked Image]

Jeff
Posted By: Bill Addiss Re: Which Switch? - 11/24/00 03:59 PM
Jeff,

From where you are you can't tell what any switches are for. And you will only leave the switch location once to go to the Attic.

Hint: No tools or test equipment needed. [Linked Image]
Posted By: rmiell Re: Which Switch? - 11/27/00 02:24 AM
Why not just turn on all three switches? That would be too easy!! Don't keep us in suspense any longer. This is a good one!

Rick
Posted By: Bill Addiss Re: Which Switch? - 11/27/00 03:44 AM
Ok, Here it is..

Turn on 1 switch and leave it on for a minute. Turn that one off and turn on another. Go to the Attic immediately - if the light is on you know it's the switch you have on. If it's off but the bulb is warm - it was the first switch. If it is off and cold - it is the last switch that you didn't try yet. [Linked Image]
Posted By: justagirl Re: Which Switch? - 12/12/00 01:59 AM
Quote
Originally posted by Bill Addiss:
Ok, Here it is..

Turn on 1 switch and leave it on for a minute. Turn that one off and turn on another. Go to the Attic immediately - if the light is on you know it's the switch you have on. If it's off but the bulb is warm - it was the first switch. If it is off and cold - it is the last switch that you didn't try yet. [Linked Image]


Man,,,bill, you are one smart guy. I would have never though of that, but it is a perfect solution for this guy
Posted By: Bill Addiss Re: Which Switch? - 12/12/00 02:18 AM
justagirl,

Thanks, but I can't take credit for the answer. I heard it from someone. [Linked Image]
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