Starting over - what to use Insteon/UPB/??

[kaldoon]

Dimmers don't require neutrals - Relay Switches and In-wall controllers need a common neutrals

[mark_anderson_us]

So I could install scene capable dimmer without a neutral and just need a neutral for the 4 button scene controller?

[Uncle Michael]

So I could install scene capable dimmer without a neutral and just need a neutral for the 4 button scene controller?

I'm not aware of all the products available, but I seriously doubt it. As I understand it, devices that have intelligence built in usually require a small amount of power even when they are "off". That is why they need a neutral, to complete their circuit when the load is powered off.

[mark_anderson_us]

OK Thanks

Guess I need to run some neutrals :-(

Got quite a bot of knob and tube to replace anyway

[Uncle Michael]

Adding a neutral wire to your switch boxes is an excellent "future proofing" step, but you should also check the detailed specifications for the switches you are considering, to see if they can operate without a neutral. I just installed an occupancy sensor switch designed for CFL control that appears to use the ground wire in place of a neutral. (The ground connection is required for it to operate properly, according to the instructions. ) I would have guessed that is not to code, but it's made by Leviton and it's UL approved, so I wouldn't rule anything out entirely.

[mark_anderson_us]

Thinking about it, I don't see why it wouldn't work. Isn't the neutral tied back to ground in the service panel (assuming you only have one panel). I looked in mine and there are some neutrals, but they're all mixed in on the same bus as the ground

[Uncle Michael]

I am not doubting that it works, but there should be NO current on the ground wire. A GFCI will trip in msec if it detects any. That's why I'm surprised that it's ok to deliberately use the ground wire to complete a circuit. Maybe current below some threshold is allowed? I'm no expert, just surprised.

[mterry63]

Although neutral and ground both connect to ground at the panel the difference is this -

The neutral conductors carry current. Current on electrial conductor having some resistance = voltage drop. So current carrying conductors ALWAYS have some voltage on them (getting smaller and smaller as they get closer to true ground). Most 15 or 20 amp circuits when loaded have lots of voltage.

The ground conductors on the other hand should NOT normally carry current (it's there for safety purposes only) and therefore have no (or little, in practice) voltage. So when a fault occurs you have a safer path to ground.

I'm no expert, and a little electrical theory can be dangerous. The concept of ground for example. Ground is ground, right? What happens when a high voltage cable falls on the ground? Ground potential is forced down into the earth somewhere several feet below the point of the contact and the potential forms a vortex pattern around that point below the surface (think funnel shape with the widest part at the surface). As you walk toward the cable a person with a 3 foot stride now has his feet at 2 different potentials that get increasing larger as you get closer, until 'poof'. You're dead.

[rsisson]

Got a chance to go over to the house today with a spare plug-in dimming lamp module and a communications module and run some communications tests...

From one end of one structure to the far end of the OTHER structure, I still had 87/100 signal strength an 0-noise. WOW. I then tried some of the outbuildings that were "invisible" before. 83/100 with 5-noise. Walking around and plugging in various plugs I had a few that were really noisy (7) that up-start complained about, but I still had 80+ signal, and since I need (<10) to work...I don't think I will have a problem using UPB even without a coupler... WOW...

[nightwalker]

but get a coupler anyway, you won't regret it.