Visonic MCT-340 E Contact Sensor




The Visonic MCT-340 E contact sensor works great for monitoring doors and windows. It blends in well with white-framed windows and white-painted doors. Additionally, it’s small enough that it’s not really noticeable. The sensor’s thin profile and sleek, modern look help keep it from being an eye-sore. It has decent range and battery power, and it’s one of the cheaper options on the market as far as SmartThings-compatible window/door sensors go. Not only that, but it reads temperature too!

This sensor operates as a ZigBee device. If you’re using a controller that only does Z-wave, you should have a look at these sensors instead.

Visonic advertises a 3 year battery life “for typical use”. I doubt the battery life is that good, but I fully expect the sensors to last at least 1½ years before having to change out the batteries. The sensor uses a CR2032 battery.

According to the manufacturer, the MCT-340 E series was designed to accommodate a gap distance of over 1″. I didn’t get that kind of performance in my testing. I measured the gap at a little over 3/4″, which is still better than I was able to get with the SmartThings-branded multi sensor.

Although these sensors work with SmartThings, they aren’t SmartThings-certified. That means that you’ll need to add a device handler in the SmartThings IDE before you can add them as a device in the SmartThings app. Don’t let that scare you, because it only takes a few minutes to do this extra step, and you only have to do it once no matter how many sensors you have.


  • Price
  • Range
  • Battery Life
  • Installation


The Visonic MCT-340 E series contact sensor is a decent option if you plan on monitoring a lot of windows/doors around your home. At the time of this writing, they are about 28% cheaper than most other SmartThings-compatible contact sensors (the Visonic is $18, compared to $25 for others). It has good range. Mine are currently installed about 30 feet from my SmartThings hub. I've only had the sensors installed for a month now, so I can't say how long the batteries will last. The manufacturer says they should last 3 years with "typical use".

User Rating 0 (0 votes)





First, you’ll need to pair the sensor to your SmartThings hub. Before you can complete the pairing process, you’ll need to follow the steps below so that SmartThings will be able to recognize your new device:

Slideshow- Tap or click to view

Click on Device Handlers.

Click the green + Create New Device Handler button.

Next, select From Code.

Open a new tab in your browser and go to here.

Highlight the code in the text editor using Ctrl-A, then right-click to copy.

Go back to the SmartThings IDE. Right-click to paste.

Scroll to the bottom of the window and click the Create button.

You’ll see a confirmation. Click the Publish button.

Select For Me.

You’ll get another confirmation. That’s it, you can now add the sensor in the SmartThings app.

Next, you’ll need to pair the sensor with SmartThings:

Slideshow- Tap or click to view

Let SmartThings search for the sensor. Remove the pull tab from the sensor’s battery. The MCT-340 E has a light that will flash during the pairing process. When the light stops blinking, the device is paired (whether or not the app shows it).

Once the device is found, tap Save (you can rename it now if you want to). If you didn’t get confirmation that the device was added, just go back to your Things list. It should be there.

Congratulations, the sensor has now been added!

The device handler enables all features- contact/temperature indication and battery percentage.

You should now see the MCT-340 E start to pass information to SmartThings.

Now that you have the Visonic MCT-340 E contact sensor paired, it would be a wise idea to test the range before you permanently mount it. To do this, simply go to the location where you want to use it and stick the sensor next to the magnet. Check the SmartThings app to make sure the sensor is showing closed.

I chose to use this 3M mounting tape instead of the tape that came with it. In my experience, this tape holds up a lot better over time.





I really like these sensors. They’re no frills, easy-to-install sensors with good range. Basically, you get what you’d expect out of the Visonic MCT-340 E contact sensor. The sensor does double-duty acting as a temperature sensor too, which is a nice touch.

If you plan on installing these on a lot of doors and/or windows throughout your home, you’ll appreciate the comparatively low price. Unfortunately, even at this price, the cost can add up quickly.

Other topics: