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Comment by amluto | Hacker News Reader

What’s the practical indoor range like on these? I’ve found the useful range of Z-Wave devices to be embarrassingly poor, and I think it’s largely because, in the US market, some kind of regulatory issue limits transmit power to 0dBm or maybe even less. (Z-wave LR is much higher, but it’s not ready for prime time.). ZigBee apparently allows up to 30dBm, which should more than make up for the less favorable frequency range.

Does anyone have any experience with how far it can reach through typical indoor construction?

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I wasn't aware of the purported regulatory radio limits on power, but I can report anecdotally that I found a huge jump in usability/signal strength/ownership satisfaction when I started replacing my old ZWave 1 stuff with the 500-series or above hardware (ZWave "Plus" is the name for these sometimes).

This "LR" stuff you mention is what I think some are calling the Z-Wave 800 series. It more than doubles the radio range of the 500 series stuff and greatly reduces power draw for battery devices. However, I have 500 and 700 series sensors that only need a battery change once every ~2 years or so. I don't find that to be too much, and the signal strength has been no problem for me in an old brick house. I do have a handful of powered zwave devices around though, and these act automatically as repeaters for the other devices in the mesh.

More details:

https://www.silabs.com/documents/login/presentations/design-...

I’m having a surprisingly hard time finding EU regulatory limits for Z-wave non-LR. ISTR some source saying that the FCC had a much stronger limit on power spectral density, which is where the -1dBm limit came from, and the EU may allow something higher.

I have a mix of 700 and 800 series Z-wave gear, and I find it borderline useless — a mesh hop struggles to reach one room over.

LR is a rather different thing — slightly different frequency, very different topology, and it requires explicit controller software support. As far as I can tell, most or all 800 series hardware supports LR, 700 might with appropriate firmware, and earlier chips do not. node-zwave-js does not yet support LR, but someone seems to be working on it (slowly).

Zwave has better range than zigbee because it uses a lower frequency that penetrates walls much better.

Zigbee theoretically can use this same frequency but in practice none of the devices do.

Make sure your hub has actual external antennas.

External antennas on a hub don’t help on the hop from device to device.

Anyway, I believe that Z-wave outside the US has better range that ZigBee. I’m thoroughly unconvinced that this is the case in the US, but I haven’t seen actual data.

Hopping is widely advertised, but in practice is not really used as much as you might think.

With external antennas most of your devices (unless you have a really large home) will connect directly to the hub. And even the ones that hop will go through walls better with the Z-wave frequency - this especially helps if you have lath and plaster in your home, or metal electrical boxes for the switches/outlets.

The z-wave frequency in other countries is basically the same - they are all in the upper 800's, lower 900's MHz. https://www.silabs.com/wireless/z-wave/global-regions

My Zigbee battery temperature and humidity sensors struggle to do 10m with 1 concrete wall between the receiver and sensor. Tried Aqara, Tuya and Sonoff (avoid the Sonoff one).

What’s wrong with the Sonoff one (except maybe the range, I dunno)? I have four of these, they’re reasonably accurate (within 1 °C from each other) and work fine for me.

I find the Sonoff drops off the network more than the others, the humidity sensor is well outside accuracy and drifts over time, and is the first to have run out of battery.

It's the humidity sensor that makes it a "No buy" for me.

Each zigbee device extend your reach and small usb powered repeater exists, in practice if you have a few devices, the signal reach is a non-existent problem!

Each zigbee device _that is mains powered_ extends your reach. In theory you could make a battery powered repeater, but there aren't any on the market AFAIK.

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