Security Sensor Shield

Description

This shield allows up to 4 security sensors to be connected to an Arduino with full End-Of-Line (EOL) support to detect tampering with the sensors or cable. End-Of-Line technology allows the system to detect a variety of events using a single cable pair to the sensor, including:

• Sensor triggered.
• Sensor cable cut.
• Sensor cable short-circuited.
• Sensor housing opened (even when system is disarmed)

Supported sensor types include:

• PIR (passive infrared) motion detectors.
• Microwave motion detectors.
• Reed switches.
• Glass break detectors.
• Gas detectors.
• Smoke detectors.

The design is based on the circuit used in the “Security / Automation Sensors” project in Jonathan’s book Practical Arduino, so this shield is a perfect way to build that project very simply and easily without messing around with a prototyping shield and lots of jumper wires. The full operation of the circuit including the EOL functionality is described in the book.

Features

• Supports 4 sensor channels simultaneously.
• Sensor power supply totally isolated from the Arduino.
• Red “Status” LED for each sensor channel to show sensor activity.
• Green “Power” LED to show when the sensor power supply is active.
• Blue “Power” LED to show when the Arduino is supplying power to the shield.
• Reset button wired through to Arduino reset pin.
• 100nF bypass/smoothing capacitor on Arduino supply rail.
• Overlay guide where you need it: both top and bottom.
• Gold-plated PCB surface: solders easily and very resistant to finger oil, etc.
• Requires a 5V-compatible Arduino board

Resources

• Security Sensor Shield Quickstart Guide
• Security Sensor Shield design files
• Example sketch from Practical Arduino