3 way switch digital timer

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  #1  
Old 08-05-12, 05:57 PM
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3 way switch digital timer

I am trying to add a digital timer switch to a 3 way configuration. I got the switch to work with one issue, it only works if the 1st switch in the diagram is in the on position. Please note that the other switch is a standard on off switch. If I turn the that switch off, I cannot turn the lights on from the digital timer. If I have it on, then the timer works perfectly to control the lights. To make matters a little more interesting, I do not have the more common configuration for 3 way switches. I have the configuration in the attached diagram where one switch flows through the second junction box to the lights. I am putting the digital timer in the #2 position in the diagram.

Can anyone help me to get this working correctly? Do I just need a second digital switch in the #1 position or am I SOL to get the timer to work with this setup?
 
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  #2  
Old 08-05-12, 06:17 PM
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Your time switch will need to be a SPDT model and that may be difficult to find. You may see it listed as a 3-way time switch. The first switch also needs to be a 3-way.
 
  #3  
Old 08-05-12, 06:32 PM
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Welcome to the forums!

I am trying to add a digital timer switch to a 3 way configuration. I got the switch to work with one issue, it only works if the 1st switch in the diagram is in the on position. Please note that the other switch is a standard on off switch. If I turn the that switch off, I cannot turn the lights on from the digital timer. If I have it on, then the timer works perfectly to control the lights.
A 3-way switch system will only work if both switches are 3-way switches. To make matters a little more interesting, your diagram shows two 3-way switches while your description says that ome of the switches is "a standard on off switch.

Since you say
I am putting the digital timer in the #2 position in the diagram.
do this:

In the first switch box - the one labeled #2 in your diagram, splice the two white wires taped black together. Protect that splice with a wire nut and fold it into the back of the box. Terminate the black wire from the ceiling box the the point, or common, terminal on the 3-way digital timer. Terminate the red and black wires going to the other switch box to the two brass colored traveler terminals on the digital timer.

In the second switch box - the one labeled #1 in your diagram - terminate the white wire taped black to the point, or common, terminal on your one 3-way switch. Terminate the red and black wires to the two brass-colored traveler terminals .

Put the on/off switch in your spare parts drawer.
 
  #4  
Old 08-06-12, 09:51 AM
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Thanks for the responses. Sorry for the confusion with the #1 switch description! It is a 3 way switch. What I mean was it was not a digital one like the timer switch.

As for the timer switch, it is the one in the attached link if that helps the discussion. No idea if it is a SPDT switch as recommended.

3-Way Sunsmart In-Wall Digital Timer-15312 at The Home Depot
 
  #5  
Old 08-06-12, 10:21 AM
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Some more info that might help...

The 1st switch (switch A) only has one 14/3 wire in the box that goes directly to the 2nd switch box (switch B) with the digital timer.

In terms of how it was wired before I made the replacement of switch B to the digital timer...the red and black went directly from switch A to switch B while the white from switch A went to the light as far as I can tell. The black was spliced with power from the circuit at switch B. Then there was a white wire taped black that was wired to switch B and went to the light. Maybe that helps.
 
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Old 08-06-12, 10:38 AM
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Three-way switches ARE single pole, double throw (SPDT) switches. I went to the link provided and read a few of the customer comments, one stood out. READ THE INSTRUCTIONS!

Since I do not have the instructions I cannot point you to the specific part that you need to study. The colors of the wires does NOT necessarily mean anything. The positions of the screw terminals do not necessarily mean anything. The COLORS of the screw terminals on the first switch DO mean something. The first switch will have two brass-colored screws and one black-colored screw (most typical). You need to use the two brass-colored screws to connect to the two "traveler" connections on the time switch. The time switch MAY have as many as five connections, a "common", two "travelers", a "hot" (power input) and a "neutral". If you do not have the requisite wires at the time switch you will not be able to make this work.
 
  #7  
Old 08-06-12, 09:10 PM
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In terms of how it was wired before I made the replacement of switch B to the digital timer...the red and black went directly from switch A to switch B while the white from switch A went to the light as far as I can tell. The black was spliced with power from the circuit at switch B. Then there was a white wire taped black that was wired to switch B and went to the light. Maybe that helps.
I have no idea what you're trying to explain. As Furd said,
Originally Posted by Furd
The colors of the wires does NOT necessarily mean anything. The positions of the screw terminals do not necessarily mean anything. The COLORS of the screw terminals on the first switch DO mean something.
It appears that you have not read and tried to follow the instructions I gave you in post #3. That is probably just as well. I also looked at the customer comments on the link you provided. This one caught my eye:
The 5 wire connection would not work correctly. I found a similar timer with a 3 wire connection that works great. Live and learn. [Source: 3-Way Sunsmart In-Wall Digital Timer-15312 at The Home Depot]
A "5 wire connection" implies that this device needs to be connected to neutral. You don't have a neutral conductor in either switch box. It ends at the light. You need to start by doing what the customer who wrote that comment did. That is, find a 3-way timer that only requires 3 wires - two travelers and one line or load - because that's what you have.

While you're looking for a device that matches what you have, you might want to pick up a copy of Wiring Simplified. It's often available in the electrical aisle at big box home improvement stores.
 
  #8  
Old 08-07-12, 05:25 PM
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Thanks for the tips. I haven't tried what you recommended yet because the upgrade that I am doing is actually at my parents house which I will not get a chance to get back to until this weekend.

I think that you are right that there is no neutral in the box as that is what I came up with as well after numerous hours of research. After looking for wiring diagrams for hours to see if I could find the setup at my parents house, I stumbled across the attached diagram. The top part is what i believe was the setup before I made any change although I need to verify the wiring at the terminals on switch #1 to verify.

What do you think of the proposal in the bottom part of the diagram? It seems to indicate that I can still use this switch without the neutral.
 
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Old 08-07-12, 06:16 PM
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Is that in the instruction manual? I think very poorly about hooking a "neutral" lead to an equipment ground. Besides, that puts the time switch in your FIRST switch position and you have stated you want it in the second switch position.
 
  #10  
Old 08-07-12, 06:33 PM
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It was not in the instruction manual. I found a website online that gave me all of the options for connecting this particular switch given the wiring situation of the house. About half way down the page, I came across the diagram that seems to be exactly what I am dealing with although I need to verify the wiring some more. What are the concerns with connecting the neutral to the ground wire? I'm no electrician so I am not clear on whether this is hazardous in any way.

Here is the website that I found the diagram...
How to wire GE 15312 timer
 
  #11  
Old 08-07-12, 06:51 PM
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Equipment grounding conductors are for carrying FAULT CURRENTS ONLY and this is to facilitate the tripping of the associated branch circuit breaker. By utilizing the the equipment grounding conductor in the manner shown by that website you are now using the EGC in a manner contrary to the electrical code. Granted that the current flow required to operate the digital circuitry is small, nevertheless it IS a potential hazard.

Worst case scenario is that if the digital circuitry failed in some way it could impress as much as 120 volts onto ANY grounded metallic surface in your home. You REALLY need to find a different time switch or else run additional wiring.
 
  #12  
Old 08-07-12, 07:55 PM
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What do you think of the proposal in the bottom part of the diagram? It seems to indicate that I can still use this switch without the neutral.
I will self-manage and not say exactly what I think of it in this public forum. My specific observations and concerns are:
  1. The ungrounded power is carried from the light outlet to the first switch box on the black conductor, not on a white-taped-black conductor;
  2. The white wire from the timer is T-tapped into the Equipment Grounding Conductor;
  3. The blue wire from the timer is T-tapped into a white wire that is connected to the point terminal on the 3-way switch in the second switch box on one end, and to the hot wire for the lamp on the other end; and
  4. Only the point terminal and one traveler terminal are connected on the timer and on the 3-way switch. If this setup will work at all, it appears that it will only work in the way you are trying to avoid. That is,
    If I turn the that switch off, I cannot turn the lights on from the digital timer. If I have it on, then the timer works perfectly to control the lights.
 
  #13  
Old 08-07-12, 08:40 PM
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I appreciate all of the feedback and honest opinions even if they are self managed!

I'll pick up a timer switch that does not require a neutral and install that! Thanks for the input.
 
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