I am trying to make a sensor for my mailbox. I used several types of zigbee contact sensors (I 3D printed boxes and sealed them in for dryness. Everyone has failed once the temperature has fallen below 10 degrees F. I need a solution here that will work in low temperatures. I have spent a ton of money already trying different sensors. My experience is the sensors will work again if I put them in pairing mode then reconnect them. They don't just start working again once they warm up. Any suggestions? I like the idea of yolink but they don't work with Hubitat.
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I use an outdoor blink camera and ifttt. I get an announcement or notification (depending) when mail arrives.
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From memory there was a lengthy thread from a few years ago where I think it was one of the regulars here did a mini project for mail detection. I'll see if I can find it
I can't remember if this is the one or not, but it includes a few links to similar projects people have done.
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My issue is temperature. Most device quit working below 14 degrees F. Sometimes it get below zero here. Usually not too low but it's around zero.
What kind of sensors have you tried? Those that use CR2 batteries would tend to peform better in low temps than the ones using wafer cells. I've had an Iris V2 Zigbee contact sensor in my mailbox since 2017; it easily handles New York winter temps (-13F was the lowest I can recall). I do battery changes yearly though I'm certain I'd get more than 12 months out of the CR2 battery; I use another in my freezer and its battery lasts almost 2 years at temps around -4F.
Only weatherproofing I have done is wrap the sensor in plastic film. Box is at the street about 80' from my house and sensor never has required rejoining. It's mounted underneath and parallel to the front edge of the box; a magnet glued to the bottom edge of the door trips the sensor when the door rotates down to the open position. It happens to fit neatly into a recess below the floor of the box and is not visible.
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What about an (outdoor) Hue motion sensor? Would detect IR and illuminance, either of which could work as a trigger. So far mine have worked in direct sun for 90+ deg. F and -15 below.
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I have the same conditions. About 40' to my hubitat. I have tried to use aqara contact with a cr2450 battery, I had one that had a CR2 battery (3v looks like AA but shorter) can't remember what the name of it was, then the one that failed last night due to cold temps was a Sonoff S1 switch that I modified with a reed switch which worked until it got too cold. I use a lot of sonoff basic switches outside in water proof boxes and they do fine. I guess its a Zigbee thing not to be able to handle the temperatures. Do you have a like to the sensor you are using? I will look into getting one, I just want to make sure I get the right one. Thanks!
I wouldn't mind trying the motion sensor, however it would only work inside the mailbox. I am afraid the signal wouldn't be able to get out.
I am using the Visonic MCT-370 which they state is their long range sensor. My mail box is thick steel and this sensor works fine..uses the CR-2 battery.
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I've used this for a year or two and it has been as low as 2 F with no problems. Battery life isn't great, about 6 months. It works well though. I have a hardwired Leviton dimmer about 4 feet away in a straight line through a brick wall. It seems to get good connectivity through that.
The Iris V2 Zigbee contact was discontinued by Lowe's a couple of years ago and since then was often available from resellers. Unfortunately the supply of these has dried up : Iris Contact Sensor 690400 / 3320-L | SmartHomeDB
The Visonic MCT-370 that @lsbrodsky uses sounds like a good bet.
You could always try different battery types by hooking up “battery holders” to the sensor terminals. I did this in a few devices that drained cr2450 batteries pretty quickly. Maybe AA would operate better?
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My mailbox is 200 ft from the house. I replaced the Mail Chime's tiny 12v transmitter battery with a battery holder (10 x 1.2v li-on rechargeables). It starts failing around 32f.
I'm going to give this one a try. Found one on eBay for $16.90 free shipping.
I use this mounted right on the front door of the mailbox, it's a tilt sensor that triggers when the door is open. Ecolink Z-Wave Plus Garage Door Tilt Sensor TILTZWAVE2.5-ECO - The Smartest House
This is the second winter I've been using it, with last winter getting down to -18 degrees, and the mailbox is 200 ft from the house. It uses the CR123A battery (the bigger version of the CR2) They claim 5 year battery life (because it doesn't take temperature readings and only polls twice per day unless triggered) I've been using it almost 2 years now and haven't changed the battery with it being outside. The device page says battery is still 42%.
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I found an Iris on ebay (they do not sell these anylonger) and it's working in the cold!!! Thanks alot for the suggestion. You guys ROCK!
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I decided to try the zigbee Visonic MCT-370 SMA contact sensor recommended above. Works perfectly at about 125 ft from my garage wall where there is a SONOFF S-31 Lite zigbee smart plug functioning as a repeater for some Sengled bulbs. The only downside is that the MCT-370 apparently does not report battery status. I guess I'll know it's done when I don't get a mid day "Mail Delivered" announcement. Not exactly mission critical.
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Do you have a vendor you can suggest for that sensor?
I just ordered one off eBay.
Yeah, should have thought of that-duh! (Makes another coffee…)
