I am new to home automation and have been lurking and reading alot. I took the dive and bought a bunch of equipment so that I could start automating my lights (Google Home, Smartthings hub, bunch of GE switches, and some motion sensors). As I was trying to install my smart switches, I ran into an issue where non of my switch boxes have a ground circuit. I tried searching the forums but could only find threads where folks did not have a neutral (something that does not affect me).
My question is, do I need a ground for these switches, and if so, do I just tap the neutral wire as these are electrically equivalent? Your help is greatly appreciated.
Neutral and ground are not the same thing when it comes to safety. Never try to use one for the other.
As far as what you do when you don’t have a ground, I will leave that to the electrical experts to answer. Wiring code is different in different countries regarding this matter. In some set ups it is possible to ground a device to the metal pattress box but you really need to know what you’re doing to make that decision, and it still might not be to code. So again, I’ll leave the remainder of the discussion up to the electrical experts.
Around 20 years ago. Ground wire is not required in residential home in many states. So it’s possible you are one of the unlucky few. Or another way of grounding is by using metal conduits and boxes instead of a bare ground bare wire. So if you have metal conduit from your metal box all the way to your circuit breaker then you can use that for your ground.
If not… Well, the only option you have is to run a ground to that box. It’s not safe to use grounded switch without a ground and neutral is not your ground so don’t do it.
There are in wall micro relays out there that don’t required ground. I believe Aeon, Monoprice and Fabiro don’t need ground for their relays. It’s a possible option for you but depend on your wiring configuration.
Sounded like you do have ground from the box. You can confirm this by measuring resistance between the metal box and neutral. Should be pretty close to 0 Ohm. Or you can measure voltage between line hot and the metal box. You should have full voltage. 110v or 120v.
As for not using the ground. The purpose of a ground is to protect you from electrical shock and giving less risk of a fire when the switch failed or faulty. So the risk is there and it’s pretty high when dealing with electronics and high voltage. Also you live in a condo which with stricter rules and insurance policies correct?
True - I’ve heard - and I’m far from a pro that NEC does not require it, yet some localitys do. I do know some electricians always do if they run conduit. Usually it’s in a commercial application, and the conduit is often exposed.