Experience with battery life on Monoprice Shock sensor?

I have this device:
Monoprice Shock Sensor

It's Z-Wave Plus paired in non-secure mode. It's on a mailbox, so typically sends a signal twice per day. Battery is a Lithium CR123.

I can't get more than 2-3 weeks battery life, which makes it pretty much unusable. Does anyone else have a similar, or even dissimilar, experience?

Sorry none. I have a Xiaomi coming and can let you know how that one does if you're interested. You're in California right? So not in cold temps? And I mean COLD, like 40 or lower.

I also have one of the new SmartThings multi-sensors, but not getting vibration or XYZ motion sensing at this point. @mike.maxwell is looking into that. I have it paired with Wink right now to see if it receives any firmware updates. Anyway, so far (and we're only talking 4 days with no activity) the battery has not budged. So that's not a true test of anything other than to say it at least does not at this stage seem to be a ridiculous battery vampire.

Florida, but same concept. The last battery never got below 45°F. The first one was likely never below 60°F.

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Ouch! That sounds like a defect or just a really weak signal. I think I would bring that close to the hub for a week and see if the battery drain stabilized.

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Is your mailbox metal?

I'm going to see how today's fresh battery fares (and keep notes on reported level by day). For the next test, I'll leave it near the hub.

Yes. The sensor is mounted under the box with a clear LOS to my front door.

Wait, just under the box? Not inside? That's enough to trip it?
When you say LOS, how far are we talking?

Yes, under-mounted and does well to detect a shock when the door opens (the latch is pretty solid, so it takes some force to dislodge the door). It helps that the Monoprice has an adjustable sensitivity pot.

I previously used an ST zigbee sensor that was too sensitive and I couldn't adjust it. Even with a lot of false acceleration reports, the battery therein was good for six months.

From the undermount, there is a small metal lip that possibly disrupts the radio signal back to the front door; but it's mostly clear LOS. It's about 40 feet to the front door. Outside the door is a Z-Wave device that may or may not be repeating.

48 hours from a fresh battery and the DH reports 50% battery. When new, the battery showed 3.28 volts. I pulled it and tested it now at 2.92 volts. IOW, it's going fast. :blush:

Well, if the z wave device isn't repeating, how far inside your house is your hub?

Hub to all-glass front door is 40 feet. Almost a clear LOS.

Then another 40 feet from the front door to the mailbox.

Possible repeaters are a GE Outdoor plug outside the door and a couple of older GE switches just inside the door.

Did you try bringing the device in and putting it near the hub to test? That's the only way to tell if it's from a weak signal or from a faulty device.

Not yet, but that's my next step. I'm going to let it deplete this battery as-is for a baseline, then I'll start fresh near the hub.

Another 72 hours and the DH reports 40%. Multimeter measures voltage at 2.84 volts.

After 8 days, having started with a new battery, the voltage has dropped to 1.9v, so, dead. I've brought it into the house near the hub and am sacrificing a new battery (starts at 3.28v) to see if distance makes a difference.

24 hours of a new battery, placed very near the hub, shows voltage drop (from initial 3.28v) to 2.94v. I'll give it another 48 hours, but I'm thinking now that this device must be defective.