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Comment by amiga-workbench | Hacker News Reader

I always wished that a lot of home automation stuff would use powerline networking. Especially things like the relays I have on my lamps.

I guess an ESP8266 costs way less than all the chunky passives required to do powerline comms though.

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Powerline networking is really noisy, the electrical wires are basically antennas. It may be easier to monitor and interfere with than wireless protocols.

There are powerline home control protocols. X10 is the big one but it is old and flawed. UPB and PLCBUS are new ones but they are proprietary. Insteon is interesting one that can do wireless and powerline but recent products have dropped powerline.

I think Matter is going to kill need for powerline. Matter goes over Wifi, Bluetooth, Thread, and Ethernet. Thread is low-power mesh like Zigbee, but should be able to use Wifi or Ethernet to bridge gaps.

IEEE 1901 can't be jammed as easily, though. 500mbps half duplex may not be amazing compared to normal WiFi, but it's plenty for a bunch of security cameras and an IoT sensor or light bulb here or there.

In every IoT scenario other than window and moisture sensors, you generally have access to a plug of some kind. I'm honestly surprised that HomePlug isn't built into IoT devices more often.

Powerline doesn't work across phases, which is in itself a huge pain with US split-phase service.

I’ve read that this can be solved with a couple capacitors to jump the phases. Just a high-pass filter. Could be an embedded in a 240v device if you want to avoid messing with household wiring.

Ubiquity had some power line equipment on a newer standard that was sensitive enough that for many homes there were enough cables running in parallel the signals would propagate between phases enough to work. Some other vendors still sell the tech - it's come a long way from X10 in the '70s!

You also have plug in phase couplers that you can put wherever you have a 220v appliance like a dryer or range. Handy especially for older houses where running new cable can be a significant challenge.

True, but older houses are also less likely to have 220V runs in the first place, I think. That might be a Baltimore thing, though - not sure I've ever seen one in residential here, but this is also the city where municipal gas service was born, so it isn't a surprise for gas-fired ranges and dryers needing only 110V service to be ubiquitous here.

I don't know if I'd want to depend on incidental capacitive coupling to carry signal between phases. I guess if it works it's likely to go on doing, but I feel like there's got to be some pretty sharp bandwidth constraints for noise, especially in residential...

And for ethernet and PoE stuff the cost is all in the jack, it needs filtering and magnetics, etc to comply with the new fast standards making it usually one of the most expensive components on the board, often many dollars for the one component

Single pair Ethernet would be a great option for home automation.

I think it is mostly used for industrial applications at the moment, but don't see why it cant be used in consumer applications as well

Insteon is alive and does a great job of propagating over powerline and dual band versions even have a little radio for hopping across phases.

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