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Smart Alarm Accessories

10 products

Showing 1 - 10 of 10 products
Veho Cave Wireless Smart Alarm Contact Sensor - Tech4
Veho Cave Wireless Smart Alarm Contact Sensor - 3 Pack - Tech4Veho Cave Wireless Smart Alarm Contact Sensor - 3 Pack - Tech4
Veho Cave Wireless Smart Alarm Motion Sensor - Tech4
Veho Cave Wireless Smart Alarm Motion Sensor - 3 Pack - Tech4Veho Cave Wireless Smart Alarm Motion Sensor - 3 Pack - Tech4
Cave Wireless Smoke Alarm - Tech4
Cave Cave Wireless Smoke Alarm
Sale price£99.95
Sold Out
ERA Protect Door or Window Contact Sensor - Tech4
ERA Protect Pet Friendly PIR Detector - Tech4
Ring Alarm Contact Sensor - Tech4Ring Alarm Contact Sensor - Tech4
Ring Ring Alarm Contact Sensor
Sale price£29
In Stock
Ring Alarm Slim Magnet - Tech4Ring Alarm Slim Magnet - Tech4
Ring Ring Alarm Slim Magnet
Sale price£5
Sold Out
Ring Alarm Motion Detector - Tech4Ring Alarm Motion Detector - Tech4
Ring Ring Alarm Motion Detector
Sale price£39
In Stock

You can easily expand your smart alarm system with additional sensors and door/window contacts. Starter kits get you going but you’ll likely need more door contacts, more window contacts and more PIR sensors.


Door contacts are a two part sensor, one part fits to the doorframe and the other part to the door. All the time the door is shut the contact is made and the alarm system can then tell the door is “safe”. However if the door is opened whilst the alarm is in “Armed” mode then it’ll trigger a breach which will sound the siren and alert your smart phone so that you can take action.

Some smart alarms can also trigger other smart home devices when breached such as turning on smart lights and alerting via voice assistants such as Amazon Alexa.


Much like standard alarm systems, smart alarms also feature battery powered PIR detectors that detect movement and can trigger your alarm. These PIR sensors are easy to install simply by screwing in place. We’d recommend putting them in areas where entrance could be gained to your house i.e the hallway, the kitchen etc.

If an intruder was to gain entry to your home whilst the alarm is armed the PIR sensor would pick up on the motion and trigger the alarm, sounding sirens and alerting your smart phone. Most smart PIR sensors are pet friendly so are designed to ignore small to medium pets such as dogs and cats. If you have pets then you should ensure that the system you choose has this feature.

At TECH4 you’ll find a wide range of PIR sensors, motion sensors, door contacts, window contacts and more for smart alarm systems

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