First Alert zwave smoke and carbon monoxide detector

Hello! I have a few of these around my house. For the most part, they work okay. The battery level meter doesn’t seem to work right. When the device starts reporting below 80%, they start beeping, but the app doesn’t know. Anyone have similar issues? I doubt there’s a fix.

For some reason you have to press the test button these ever so often for the battery level to be updated in the app.

2 Likes

Battery monitoring on IoT devices is notoriously bad. that 80% probably means dead. Or it could mean - hey I feel tired today. You can really only use them as a guideline. If it consistently happens like that then start planning on replacing the battery at 81%… That may just be the time you need to replace the battery.

I’ve got one Zigbee sensor that always drops to 75% the day after I replace its battery and it will stay there for MONTHS. then suddenly one day it’ll drop to 20% and die about a week later. I have another of the same make that has a nice smooth ramp down and yet another (same make) that drops to 30% after about 6 months and will keep on trucking till it reaches 5% I’ve got separate battery alerts setup for each device to catch them - but the alert is ALWAYS based on past performance. I’m installing a new door sensor tonight but wont setup it’s battery alert until next year - after I know how it’s going to behave.

2 Likes

Actually there are significant differences between Z-Wave and ZigBee devices that should be noted. Z-Wave devices ALWAYS report the % remaining. So that mean the device itself is responsible for calibrating the remaining battery capacity and the battery voltage.

ZigBee devices on the other hand can report either the % remaining (in which case it behaves like Z-Wave devices above) OR it can report the battery voltage. In the latter case it’s upto the device handler to translate the voltage to a % and it should account for battery type (LiIon, NiMH, Alkaline, Lithium etc). Most DTH’s don’t do this well since LiIon batteries have a non linear curve. Plus things like load voltage can impact the curves which need to be handled by the DTHs’. It’s explained in more details on this post: [RELEASE] Low Battery Notification with Customizable Alert/Warning/Monitor, Configurable Thresholds and Device Monitoring Alerts

It can also happen that the battery updates may be lost in the mesh which can then cause significant delays in reporting, so if you press the button and see the battery % change then it may tend to indicate mesh trouble also.

1 Like

Thanks, everyone who responded–this is helpful!

1 Like

Lear something new every day thanks @RBoy. (admittedly ZWave is better but its still not rock solid consistent)

Which is why I highly recommend RBoys battery monitor. It’s good stuff.

1 Like