Replies

1. 
   maddog3 | Oct 30, 2005 03:45pm | #1

   ...lamp the fixture and the "problem " will go away.......

   "
2. 
   BillHartmann | Oct 30, 2005 04:23pm | #2

   What you are reading is called "phantom voltage".

   The meter (bet it is digital) has a very high input impedence and the open wire is capacitively coupling to the hot wire and that is what you are reading.

   Probably the equivalent of 50,000,000 ohms or more. So it can not deliver any power. And as MD said if you put a load on it (light bulb) then it will go a way.

1. 
   DanH | Oct 30, 2005 04:29pm | #3

   Note that, even with the fixture lamped, if you meter at a switch you'll read phantom voltage on the unused traveler, when the lamp is on.--------------
   No electrons were harmed in the making of this post.

1. 
   loykd | Oct 30, 2005 04:33pm | #4

   So this is normal?

1. 
   DanH | Oct 30, 2005 04:47pm | #5

   Perfectly. May be the only normal thing in your house. ;)--------------
   No electrons were harmed in the making of this post.

2. 
   jhausch | Oct 30, 2005 06:37pm | #6

   Think of it this way:

   The electricity is cycling at 60Hz.  ROughly meaning that the electrons are being pushed and pulled 60 times per second within the wire.  That changing electricial field creates a changing magnetic field around the wire.  That changing magnetic field is "inducing" voltage in the traveler.  Sort of like how a transformer works. 

   As mentioned, the there is volatage there, but nearly 0 current. 

1. 
   loykd | Oct 30, 2005 07:56pm | #7

   Not as "normal" as I was hoping... Either this is symptomatic of a bigger problem, or I have a completely different problem in how I've wired the circuit.This circuit is wired with the fixture between two switches. Power comes to the first switch and is shared with another 3-way switch and a 2-way switch. This circuit works properly if the other 3way switch is in one position, but it shorts out if the other switch is flipped. I gotta dig into this more this afternoon. Any suggestions on things to look at?

2. 
   BillHartmann | Oct 30, 2005 08:08pm | #8

   If I follow you this is the way that it should be wired.http://www.selfhelpandmore.com/switchoutlet/3way/3waypwswthrufx.htmHere are other combinations of 3-way wiring.http://www.selfhelpandmore.com/switchoutlet/3way/index.htm

3. 
   maddog3 | Oct 30, 2005 11:43pm | #11

   it sounds like he has his whites mixed up"

4. 
   loykd | Oct 31, 2005 07:18am | #12

   Bill, Thanks for those links.  I've studied, looked, looked and studied and still, something is kicking my butt.  The circuit works properly when switches are in one position, but it shorts when I flip the switch.  Could a switch be bad?

   Also, my comment about the 2-way switch, I think, is maybe a red herring and shouldn't affect this circuit.  It's a regular switch which controls a completely separate fixture and I mentioned it only because it shares the circuit (and switch box) as the 3-way switches.

5. 
   BillHartmann | Oct 31, 2005 07:53am | #13

   It "could" be a switch that is shorting to the frame and thus ground, but I seriously doubt that is the problem.If it is not a wiring mistake them it probably cut insulation some place.At the head end (where the power feeds in disconnect the hot, neutral, and ground.Then ohm all 3 combinations (hot - neutral, neutral - ground, & hot ground) with the switches in all combinations and without a bulb in the socket.In no case should there be any continuity between the ground and either of the other leads.And without a load (bulb) then there should also never be any continuity between the hot and neutral.Which one shows the short will give a clue as to where the problem is.

6. 
   DanH | Oct 31, 2005 12:54pm | #14

   You don't, by some chance, have two separate circuits here, do you?--------------
   No electrons were harmed in the making of this post.

7. 
   loykd | Oct 31, 2005 03:58pm | #15

   Dan, I'm not sure that my nomenclature is right, but on a single breaker, I'm powering three circuits (sets of fixtures), and those switches are all in a single box.

8. 
   bosn | Nov 01, 2005 01:05am | #16

   A "circuit"  is everything attached to a single breaker.  A set of fixtures would be a "switch leg".  I think you have a couple of white wires mixed up.  One that should be a neutral is hooked up as a traveler or vice versa.  It's a simple mistake to make in a multi-gang box full of wires,  especially if you have three ways in the box and?or you are a novice.  Check your work again, and any white wire that you know is a traveler, mark it's entire exposed length with a blue permenant markerThere are no electrons!  It is all made up.  Don't believe it.

   Electricity is made by GREENIES.

9. 
   loykd | Nov 01, 2005 04:07am | #17

   I'm losing the fight with this one. I've checked and doublechecked the wiring and just can't figure it out.Bill, I'm sorry to say that you lost me on shooting those wires.

10. 
    DanH | Nov 01, 2005 04:41am | #18

    Maybe what you should do is go to the HW store and get some more switches and a couple of your standard "basement" ceramic light fixtures. Get some pieces of romex and wire them together on the kitchen table (or maybe stapled to a piece of plywood) the way you think they should work, making an effort to have the wiring be similar to what you've got installed. Put a plug on one end so you can plug in to an extension cord, and test the circuit.Then, when you have that working, go back and figure out what you're doing wrong with the installed wiring.One way to go wrong is to get confused about the three terminals on a 3-way switch. But from the sound of it you have another problem. The other major cause of trouble is getting confused about how to run the wires when you have the switches physically on opposite sides of the light fixture -- there's a tendency to forget that they must LOGICALLY appear to both be on the same side of the fixture.A final problem that may occur is that you simply have not run enough wires. It's easy to get confused about the number of wires needed for a 3-way switch setup, end up with too few wires, and try vainly to make them work.--------------
    No electrons were harmed in the making of this post.

    Edited 10/31/2005 9:48 pm by DanH

11. 
    DanH | Oct 30, 2005 10:23pm | #10

    I assume you mean you have two 3-way switches and a 4-way. (The "way" being a traditional misnomer -- referring to how many connections are on the switch.)--------------
    No electrons were harmed in the making of this post.

3. 
   MarkH | Oct 30, 2005 08:32pm | #9

   Real electricians use wiggies.  Us tech types use DMMs and some get confused.  I do have a background in electrical work so if I saw 30 volts, I would do as someone said and just screw in a bulb, you'll have pretty much 0 vac I bet.