I use UPB (Universal Powerline Bus) switches, relays, and dimmers, from two different manufacturers: Simply Automated, and PCS Pulseworx.
My installed UPB Devices
Simply Automated™ brand:
(4) x US11-40, Single rocker dimmer
(4) x US2-40, Universal dimmer controller
(2) x US22-40, Universal dual dimmer controller (2 separate 120V circuits)
(1) x UML-20-W, Heavy Duty UPB dimmer module (max 400 watts dimmed)
(1) x UMA-20-W, Heavy Duty UPB relay module (max 15 amps switched)
(1) x ZPCI-W, Wire-in phase coupler (not currently needed or in use but tested ok in past.)
PulseWorx PCS™ brand:
(5) x FMR1-20 Fixture Module Relay (max 20 amps switched)
(1) x WS1C, 0-10V Relay Dimmer. I use this to control a large 0-10V dimmable outdoor 120V-powered LED flood light. Note, the WSC1C does not supply mains power to the flood light. All it does is remotely set a 0-10V DC control signal which tells the outdoor dimmable flood light how bright it should be. (Or, off.)
(1) x RM-0-10V (receiver module fo WS1C, not directly addressable by UPB)
When I did a total electrical re-wire + new panel in my 1300 sq ft. single-family home 3 years ago I ran 3-conductor cable (hot / neutral / ground ) to every switch and outlet box. I used a SquareD QO-series panel and matching SquareD combination GFCI-AFCI breakers on every circuit. Additionally, every circuit is also protected by a good-quality wall-outlet GFCI which feeds all outlets on its branch downstream. There’s also a SquareD plug-in whole-house surge protector at the panel.
My UPB setup has had no reliability problems at all related to any of these other components.
I installed UPB dimmer-switches at every wall light-switch location, giving me complete on/off and ~20%-100% dimming capability on all of the standard A19-type CREE LED light bulbs in ceiling fixtures. (Side note: of ~25 CREE 60W LED bulbs I installed in 2014, only 2 have failed. These were in the bathroom & died gradually (intermittent flashing) over a number of months, presumably due to high humidity from the shower-over-tub.) Of course OpenHAB controls all of this through the UPB binding, via an RS232 --> Powerline interface device.
The reason I chose hard-wired UPB over a free-space RF (radio-frequency) solution is reliability. I don’t trust RF to be absolutely reliable, especially in a dense urban environment. UPB is a relatively low-frequency, high-voltage signal carried directly on the house’s 120V wiring. Due to my strong bias towards reliability I will probably never use ZigBee / Z-wave or similar sorts of RF-mesh devices in any part of my HA / Security setup. Copper wire is comparatively expensive & hard to install compared to RF, but it is typically 5-nines reliable (when correctly installed) compared to 1- or 2-nines reliability for RF signals. In the long run I enjoy the luxury of not having to think about interference, battery life, re-pairing devices and sensors that lose track of themselves, etc.
I have a total of12 UPB wall-switch dimmers, 5 UPB on/off relays. So far I have had one equipment failure: the RS232 --> Powerline interface device (between the OpenHAB server & the house wiring) failed. It was replaced under warranty at no cost. None of the switches / dimmers / relays have failed yet. One of the switches cycles on/off at least 48 times a day, controlling a ventilation fan which runs for 15 minutes per hour. (NB: that fan itself is actually powered through a separate dumb relay, to isolate the UPB switch from motor start-up current / voltage spikes. So, the UPB switch in that instance sees only 20 or 30 milliamps of current needed to close the relay.)
UPB does have a couple of minor quirks. Due to the fairly low data/baud rate over the wire (I believe it’s around 4800 baud,) there is perceptible lag when sending commands to remote groups of switches. I’d estimate it at about 250 milliseconds or so. There is also some lag even when operating a local UPB switch directly connected to a load – perhaps 100 milliseconds. It’s a bit different from the effectively “instant-on” of a plain hard-wired electrical switch.
Reliability of command sending/receiving is quite high but certainly not perfect. Subjectively speaking UPB commands over the house wiring are successfully transmitted & executed about 99.9% of the time – that’s 999 times out of 1000 – but UPB should never be used as the sole or primary control method for life-critical or safety-critical control systems, unless there are redundant fail-safe mechanisms built in to the overall system. (For example: using UPB to directly control heaters that do not have their own thermostats built it: what happens if OpenHAB sends a UPB command to turn off a heater but the command isn’t received and executed?)
Module cost seems to be too high to me. $60-70 for the least-expensive single-circuit switch, going up to $90-$150 for multi-circuit switch/dimmers and auxiliary relays. Compared to the real cost of manufacturing these devices these are sky high margins. The cost just reflects the fact that the market for such devices is very small (compared to the # of potential homes they could be installed in,) so the manufacturing volume is very low & the per-device cost high. You have to pay if you want to play.
I like UPB’s reliability but I am uncertain about its long-term (>10 to 20 year) viability as a technology. Leviton RF products seem to have deeper market penetration. In market sectors like this there’s no guarantee that “the best tech wins,” marketing & industry collusion are signficant factors, see VHS vs. BetaMAX in the 1980s. So, as a hedge against the chance that UPB manufacturers drop the tech entirely, I keep a second RS232 --> Powerline interface in my box of replacement parts in case the primary one fails. (If the RS232 --> Powerline interface fails, ~$1500 to $2,000 worth of installed UPB devices will still function with local switch control but they are unavailable to OpenHAB, which would be very inconvenient.)
At the OpenHAB level: I use OH to automatically change indoor & outdoor lighting levels and scenes according to the current dawn/dusk time (as provided by OH’s Astro binding.) I also use it to control a bathroom exhaust vent fan which is adequate to pull fresh air into the entire house if the windows & doors are configured correctly. I’ve set up a mode to randomly activate lights in certain rooms for occupancy-simulation. At some point I would like to integrate OH with my separate hard-wired home security system so that outdoor motion sensors could trigger DMX-controlled RGB LED strips in every room to blink in certain colors to signal caution or danger, but I haven’t implemented that yet.
I should also add: I’m still using OpenHAB 1.x dating from about 2015, due to the “if it’s not broke don’t fix it” principle. I look forward to moving to OH 2.x sometime but it will take 20-30 hours or more of testing and re-integration, not something I’m ready to take on any time soon.