I have a couple of 2-wire dimmers at the staircase (1 up and 1 down), I think the upstairs one controls the load and the downstairs one has no load. These are linked together in a scene.

So this morning when I get up both dimmers appear to be 100% dead. The LEDs are not on and the switches don't respond locally or through the admin console. Other lights on the same circuit are still working, so I know the breaker is OK. I pulled and reset the air gap on one of the switches, but no luck.

I don't see how 2 switches could both go bad overnight? I'm wondering if something came loose in a junction box somewhere and both switches are no longer getting power. Unfortunately I didn't have time to troubleshoot before leaving town today. I'm thinking first order of business will be to pull both switches and verify they have power.

 

Any other ideas what could have caused this? I'm at a loss.......

Kill the breaker and wait 30 seconds and report back success / failure. If the switch is in the same state hard reset the switch and report back success / failure.

 

I would remove the load and change it out with a new incandescent bulb while you're there.

If you replaced an old school 3 way switch setup with those 2 switches, my guess would be a wire nut on the hot (or neutral) feeding them came loose.

Edited April 27, 201510 yr by paulbates

The 2 wire dimmers do not support LED bulbs, only incandescent so it's possible that the switches are not getting the required voltage to operate properly.

The 2 wire dimmers do not support LED bulbs, only incandescent so it's possible that the switches are not getting the required voltage to operate properly.

I have a couple of 2-wire dimmers and they work fine with Cree LED bulbs.  Occasionally, they will show up as not available on the administrative console, but will work nonetheless.

 

Don

I have a couple of 2-wire dimmers and they work fine with Cree LED bulbs.  Occasionally, they will show up as not available on the administrative console, but will work nonetheless.

 

Don

 

They may be operating on the edge of the envelope. I  would assume that the RF range would be reduced if the switches aren't getting the needed voltage which is why they don't sometimes show up as available

Edited April 30, 201510 yr by Techman

I have a couple of 2-wire dimmers at the staircase (1 up and 1 down), I think the upstairs one controls the load and the downstairs one has no load. These are linked together in a scene.

 

The 2-wire dimmer cannot function without a load. A 2-wire dimmer is not suitable for a 3-way configuration. Describe the wires at each switch box. BTW, in a 3-way configuration at least one white wire is not a neutral wire.

I don't remember how I wired the switches, but I'm guessing I connected both switches to the load.

 

I've never really given much thought to how the 2-wire dimmers work without a neutral, but from the comments above I see that you must have a load. They must send a small amount of current through the bulb even when it is off?

 

In light of this, I'm thinking the most obvious (and easiest) solution is a burned out bulb? Could it really be that easy? I hope so.

The 2-wire switch cannot be used successfully in a 3-way configuration. If both switches are connected to the load, then any one switch being on will turn the on, but both switches must be off to turn the load off.

 

The most often occurring error when wiring a multi-way configuration is basing the connections on the color of the wire. In any 3-way configuration, it is unlikely that a black wire is line. In fact, line is often white. Red can be a traveler or, sometimes, the load.

The 2-wire switch cannot be used successfully in a 3-way configuration. If both switches are connected to the load, then any one switch being on will turn the on, but both switches must be off to turn the load off.

 

The most often occurring error when wiring a multi-way configuration is basing the connections on the color of the wire. In any 3-way configuration, it is unlikely that a black wire is line. In fact, line is often white. Red can be a traveler or, sometimes, the load.

The 2-wire dimmer can in fact be used in a 3-way configuration. I just replaced the light bulb and it's working perfectly, as it has been for the last 6 months or so.

 

I'm confident in my wiring skills and made sure to verify wiring scheme during installation of the dimmers. If I'm not mistaken, it is illegal to use white for a current carrying conductor in any situation, although I know in the case of 3-way switches many times that's what you find. The proper way to do it is to use phasing tape to mark the white wire at both ends, but I think even that practice has been outlawed in the NEC.

 

Anyhoo..... It was just the bulb. Next time I'll know to check that first.

The 2-wire dimmer can in fact be used in a 3-way configuration. I just replaced the light bulb and it's working perfectly, as it has been for the last 6 months or so.

 

I'm confident in my wiring skills and made sure to verify wiring scheme during installation of the dimmers. If I'm not mistaken, it is illegal to use white for a current carrying conductor in any situation, although I know in the case of 3-way switches many times that's what you find. The proper way to do it is to use phasing tape to mark the white wire at both ends, but I think even that practice has been outlawed in the NEC.

 

Anyhoo..... It was just the bulb. Next time I'll know to check that first.

To be clear for the benefit of others who may stumble upon this thread. You indicated when the bulb went out.

 

That you found the switch LED no longer lit, correct? [emoji53]

 

 

Ideals are peaceful - History is violent

The 2-wire dimmer can in fact be used in a 3-way configuration. I just replaced the light bulb and it's working perfectly, as it has been for the last 6 months or so.

 

I'm confident in my wiring skills and made sure to verify wiring scheme during installation of the dimmers. If I'm not mistaken, it is illegal to use white for a current carrying conductor in any situation, although I know in the case of 3-way switches many times that's what you find. The proper way to do it is to use phasing tape to mark the white wire at both ends, but I think even that practice has been outlawed in the NEC.

 

Anyhoo..... It was just the bulb. Next time I'll know to check that first.

 

It is in accordance the the NEC to use a white wire as the line. Otherwise every switch loop would result in two white wires being connected to a fixture. You are correct, though, The code requires that the wire be identified using color tape.

 

In any case, a 2-wire switch will NOT function as a 3-way configuration, although you can always have more that one switch connected to the load. That's known as wiring switches in parallel. In that situation, if any one switch is on, then any other switch(es) cannot turn the load off. Even the documentation indicates that the 2-wire switch is not compatible with a 3-way configuration.

 

OTOH, linking may work. But still, only if both switches are wired to the load.

Edited April 29, 201510 yr by stusviews

To be clear for the benefit of others who may stumble upon this thread. You indicated when the bulb went out.

 

That you found the switch LED no longer lit, correct? [emoji53]

 

 

Ideals are peaceful - History is violent

Correct, light bulb burned out, both switches went totally dead.

 

 

OTOH, linking may work. But still, only if both switches are wired to the load.

 

 

Correct, I have both switches wired in parallel to the load and both switches are in a scene. Without placing them into a scene together then it would not work.