An alarm motion sensor is an essential component of any modern security system. It detects the movement of objects, persons or animals within a specific area and sends a signal to the control panel, which triggers an alarm or activates the other security devices. In this article, we are going to discuss the wiring diagram of an alarm motion sensor, along with its working principles and installation guidelines.
Working Principles of Alarm Motion Sensor
Alarm motion sensors work on different principles, but the most commonly used one is the Passive Infrared (PIR) technology. PIR sensors detect the infrared radiation emitted by the body heat of moving objects. They have a pyroelectric sensor that generates an electric charge when exposed to heat changes. This charge is amplified and processed by the electronic circuit of the sensor, which triggers the alarm or the other devices. PIR sensors are cost-effective, reliable, and easy to install, making them the preferred choice for most homeowners and businesses.
Other types of motion sensors include microwave, ultrasonic, and tomographic sensors. Microwave sensors emit microwave signals that bounce off moving objects and return to the sensor. Ultrasonic sensors send sound waves and calculate the time taken for the echoes to return. Tomographic sensors use radio waves to create a 3D image of the monitored area and detect any changes in it.
Wiring Diagram of Alarm Motion Sensor
The wiring diagram of an alarm motion sensor depends on the type of sensor, the control panel, and the other devices connected to it. Here is a general wiring diagram that applies to most PIR sensors:
| Sensor terminal | Function | Control panel terminal |
|---|---|---|
| Red | Positive power supply | Positive power supply |
| Black | Negative power supply | Negative power supply |
| Green | Alarm output | Input of alarm zone |
The red and black wires connect to the power supply, usually 12V DC, and provide the necessary voltage for the sensor to work. The green wire connects to the input terminal of the alarm zone on the control panel, which is usually labelled Z1, Z2, etc. When the sensor detects a motion, it sends a signal to the alarm zone, which triggers the alarm or activates the other devices connected to it, such as the sirens, strobe lights, or cameras.
Installation Guidelines of Alarm Motion Sensor
Installing an alarm motion sensor is a straightforward process that requires some basic tools and skills. Here are the general installation guidelines:
Step 1: Choose the Right Location
Choose a location that covers the area you want to monitor and avoid any obstacles, such as windows, doors, or trees, that can trigger false alarms. The ideal height for the sensor is between 6-8 feet above the ground, facing downwards.
Step 2: Mount the Sensor
Mount the sensor securely using screws or adhesive tapes, depending on the surface. Make sure that the sensor is level and not tilted, as this can affect its accuracy.
Step 3: Connect the Wires
Connect the wires according to the wiring diagram of the sensor and the control panel. Use wire strippers and crimping tools to ensure a proper connection.
Step 4: Test the Sensor
Test the sensor by moving in front of it and checking if it triggers the alarm or the other devices. Adjust the sensitivity and the detection range of the sensor as needed.
Step 5: Secure the Wiring
Secure the wiring using cable ties or conduits to prevent any damage or interference. Label the wires for future reference.
FAQ
Q1: Can I install an alarm motion sensor myself?
A1: Yes, you can install an alarm motion sensor yourself if you have some basic knowledge of wiring and tools. However, if you are not confident, it is recommended that you hire a professional installer.
Q2: How many sensors do I need for my home or business?
A2: The number of sensors depends on the size and layout of the monitored area. As a general rule, you should install one sensor for every 1000 square feet of space, or in every room or area that you want to monitor separately.
Q3: What is the ideal detection range of an alarm motion sensor?
A3: The ideal detection range of an alarm motion sensor depends on the type and brand of the sensor. Most PIR sensors have a range of 30-50 feet, while microwave sensors can cover up to 100 feet. Ultrasonic and tomographic sensors have a shorter range but can detect movements through walls and barriers.
Q4: How do I prevent false alarms from my alarm motion sensor?
A4: You can prevent false alarms by adjusting the sensitivity and the detection range of the sensor, avoiding any obstacles or sources of heat or cold, and using pet-immune sensors if you have pets. You can also install a verification system, such as a camera or a glass-break sensor, to confirm the alarm before it goes off.
Q5: How do I maintain my alarm motion sensor?
A5: You can maintain your alarm motion sensor by cleaning it regularly with a dry cloth or a soft brush, checking the wiring and the connections for any damage or corrosion, testing the sensor periodically, and replacing the batteries or the power supply as needed.
