AC Powered Door Sensor for Cold Weather

I’m looking for a door sensor to be used in my second garage. I live in northern MN, so I could see extreme temperatures below -30 F, and regular temperatures in the winter below 0. I don’t think a battery will hold up, so I’m looking for AC powered options.

I contacted Aeon Labs because I see they offer recharge capability on their DW Sensor 6. They said it would be difficult to install since the USB power plugs into the bottom of the unit,which is meant to be installed flat against the door. Any other ideas?

What exactly are you looking for in a door sensor. Is it a contact sensor that will just tell you if the door is open or closed? Or is it a tilt sensor that will tell you when a door is moving?

The reason I ask is that there are a couple of different options, but it depends on the specific use case.

Quite a few people in Canada or Minnesota have used a nonnetworked gate sensor for open/close and then run its contacts to a smart things – compatible sensor inside the house. It’s similar to what people do with doorbells. That can work quite well and we’ve discussed some of the options previously.

Here’s a typical gate sensor:

http://www.smarthome.com/seco-larm-sm-226l-3-magnetic-garage-door-contact-switch.html

And then you would connect it to a networked sensor in the same way that people do for a pressure Mat:

If you’re looking for a tilt sensor, the Kumo wireless tags are an option. They can be used even inside the freezer and have an operating range going down to -40 Fahrenheit. There’s a community – created device type handler for them. Each tag cost about $40 and you also have to buy their ethernet bridge for $60 (one Bridge for up to 40 tags).

And one more option for contact sensor : the new sensative strips contact sensors are intended for outdoor use and rated down to -4°F.

These are a very elegant solution, I just don’t know if the operating range is sufficient for your needs.

http://www.sensative.com/strips_tips.html