Increasing battery life of z-wave sensors

Hello. I have Zooz 800 LR door sensor on my fence gates outside the house and the battery life is not as long as I’d like it to be. In general, will battery powered z-wave devices have a longer battery life if I force it to route through a plug-in z-wave device/repeater closer to it? Or is it better to try to have it route directly to the z-stick?

I don’t care much about latency for this particular node. My biggest concern is increasing battery life.

You might save battery life by re-provisioning your sensor in LR mode, which includes adaptive transmission power capability. Using LR mode requires: (a) 800-series controller that supports it, (b) updated zwavejs to 12.5 or later, and (c) you can scan the smartstart QR code. Note however that Z-wave LR uses a star topology, so must communicate directly with the controller node and cannot not use repeaters.

Another thing you can do to save battery life on Z-wave sensors is increase the sleep time between wake-up reporting — some sensors wake-up ever hour or two by default, but I find every 12 or 24 hours is sufficient for door sensors. You might need zwave-js-ui to set the wake-up parameter however.

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Thanks. I have an 800 series controller. I also have the latest version of zwave-js-ui so I’m assuming the is equivalent to zwavejs 12.5 of later (right?). Do I need to do anything special or will the 800 series door sensor connect using the LR mode automatically?

I am confused about sleep time. What does this actually mean? I’m pretty sure that even when the sensor is asleep, it will still report the open/close status. So what does sleeping do to a z-wave device?

Hover your mouse over the blue “i” circle in the upper-right corner in zwave-js-ui to verify the versions. You can also hit “CONFIGURE” in the HA zwave integration page for your hub.

You have to remove and re-add the device again using SmartStart (QR code) in LR mode, it doesn’t just automatically switch itself over. You may also need to enable LR on your controller and generate separate keys for LR security. I’m not certain whether zwave-js-ui is required for these steps or not.

Z-wave is designed so that battery-powered devices are normally in low-power “sleep” wherein they transmit only state changes; they do not listen for, or receive, any commands or config changes while asleep. They are configured to periodically “wake up” and check-in with the controller and process all the commands and changes queued up waiting since the last check-in. I set my (500-series) door sensors to wakeup every 12 hours and the batteries last over 6 months.

You can set the wake up interval in HA, however it’s a little easier in ZUI.

You don’t say how long your battery lasts, so it’s hard to know if it is expected or not. I have several of those. My observations

a) it has a pretty small battery compared to other door sensors.
b) reported battery level is very sensitive to ambient temperature and varies by 30-40%
c) once it hits 20% it still can run for a long time.

Here’s a history chart.

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Good point about battery reporting. Since my sensors aren’t mission critical, I often wait for them to just die and find that some report 0% battery for months before they stop working. I have an automation watching “last reported” which should never exceed 24 hrs.

I also have a few devices that tend to wake up and never fall back asleep, which drains the battery very quickly. A ping usually puts them back to sleep, so I’ve had to setup another automation that pings a sensor “awake” for over 5 minutes.

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The better devices have a separate low battery report. Which is just te inform you on low battery and thus takes the battery level reporting away