Your contractor used 14-3 wire which is usually designed for overhead fans or something with dual function like light & fan separate, or a 3 way switch with carrier. What is the switch next to this one do? It looks like it is wired to the black (hot)
They basically did a neutral switch. In this case the hot is going to the lamp first, then the red wire coming from the light is being switched down to neutral and completing the circuit.
white is definitely neutral in your case (they are all wire nutted together. You should get 0v between ground and neutral, and 120v between ground and hot or neutral and hot.
If you dont get 120v between hot and ground, you may have a ground lift situation which can be dangerous. Test by doing continuity between neutral and ground. You should get a reading of a few ohms. If you get an open circuit then you need the electrician to trace that out.
Given that you see 120V between white-red, only one of them is hot and the other should be neutral (so you should have a neutral wire). Based on the pictures, the white wire appears to be neutral, as @docwisdom points out.
A few things to try:
Try a non-contact voltage tester like this. This way you hold against one wire and it will let you know if it is hot or not.
Look at the wiring on the other 3-way switch, how are they connected? From the photos, it does seem that the white wire is coming from a screw wire connector that is also connected to the other switch - does it connect to neutral on the other 3-way switch?. This might give some clues (of course, unless this second switch is not wired correctly).
Ahah @docwisdom that looks similar and I will check it out later. Thanks!.. if what you say is right it means I have a ground a hot and a neutral thoughâŚ
Donât give up. I had to replace the gang box when I put in my dimmer switch because after fiddling around with it for a couple of hours, it was too loose. Youâll figure it out and next time it will be easier. Besides, itâs good for the brain to learn new skills.
My dimmer is very loud (and I thought I had significant hearing loss from working around high-decibel machinery my whole life). Do you think I got a bad dimmer and should try another. I have the dimmer running 4 60 watt incandescent bulbs.
Actually I did give up as did two electricians! Its 1950âs wiring and all the bodging thats been done to it so I have just gone with GE Link bulbs with monoprice motion sensors and rules in ST to turn on when people arrive home etc etc. I have used a few of these http://www.homedepot.com/p/Amerelle-Switch-Guards-2-Pack-CSG1/100628705 to prevent the switch being turned on and off âaccidentallyâ and they are great as one side is open so if you need to manually (shock horror!) turn the lights on or off you can easily.
I used a remote to set the parameters on the switch. I was able to set the different Z-wave parameters, and was able to change the ramp up rate and number of steps.
Can you change the parameters while ST is still connected to the device? Wouldnât you have to add the light switch on the remoteâs network and thus ST would no longer be able to control the switch?
Update: I found out that you can actually add the remote to the ST hub and have your controller and hub both work, pretty nifty. Going to pick one of these up.