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Smart Alarm Sensors

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ERA Protect

ERA Protect Door or Window Contact Sensor

  • Ideal for doors or windows
  • Two way wireless communication
  • Built in tamper protection
  • Simple one touch pairing to your ERA Protect system
  • Compatible with the ERA Protect Wireless Alarm range
Follow up
ERA Protect

ERA Protect Pet Friendly PIR Detector

  • Pet friendly PIR motion sensor, up to 25 kgs
  • Detection zone up to 12m
  • Two way wireless communication
  • Built in tamper protection
  • Simple one touch pairing to your ERA Protect system
Follow up

Smart Alarm Sensors Overview

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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