While seemingly insignificant, detectors and sensors fulfill a critical role in overall security systems. For example, businesses can use such devices to alert staff to incoming customers at the door, alert professionals when equipment overheats, activate alarms when movement is internally detected after hours, and more. Alternatively, homeowners can similarly use detectors for entrances, sensors for unusual activity outside, and more. Furthermore, both home and business owners can install sensors to detect smoke buildup and harmful gasses. 

Axis, Bosch, Honeywell, LTS Security, Ubiquiti, Verkada, and 2GIG detectors are available through A1 Security Cameras. Read other questions about Detector.

Security Detectors

What are the types of sensors?

When concerning motion sensors, the three different types include:


  • Passive Infrared or PIR
  • Microwave
  • Dual-Tech or Hybrid


Passive infrared sensors (or PIR) are mounted devices that emit infrared light and use a pyroelectric sensor to detect the difference of energy when a body or movement comes into contact with the light. Typically sending out the infrared light in a wide ark, these devices are usually used in rooms with automated lighting systems like an office, board room, or presentation hall.

What are the types of sensors?

Microwave sensors emit a specific signal at a high frequency to detect movement within its applicable range. Capable of detecting very slight movements, these devices are commonly used in military installations, law enforcement, air traffic control towers, environmental field studies, and more.

Dual-Technology sensors are similar to both other types of sensors in that they detect motion through both infrared light and microwaves. However, whereas the two formers have only one sensor that must be triggered, the hybrid sensor has two that require activation in order for it to send a signal. This means that the sensor must both detect movement and heat and is less likely to be triggered by the wind. These sensors can be used in high occupancy rooms, classrooms, or other areas specifically designed for people to congregate.

Where do you place a motion detector?

For each of the motion detectors listed above, placement should be unobstructed so the produced signal can easily detect the correlating movement. Passive infrared sensors should be placed next to entrances so to immediately so to detect newcomers or intruders. While not necessarily sold by A1 Security Cameras, microwave sensors should be placed in the open with the sensor aspect monitoring incoming traffic moving perpendicular to the signal. Dual technology should be established similar to the infrared detectors, where it can have an uninhibited vantage point to incoming visitors or intruders.

Where do you place a motion detector?

What can trip a motion sensor?

For each motion sensor displayed on A1 Security Cameras, motion will activate the device after installation. As mentioned above, infrared detectors will be activated by whatever returns a detectable amount of heat. That can include people, animals, and machinery. Dual-technology detectors work similarly, but with the caveat that they must detect both heat and movement in their range. Generally, the latter device cannot necessarily see static machinery but will detect people and animals.

What are the three types of smoke detectors?

The three types of smoke detectors include:


  • Ionization
  • Photoelectric
  • Dual detectors


Ionization smoke detectors use a slight amount of radioactive material placed between two charged plates. The setup ionizes the incoming air, which sends a signal when smoke interrupts the airflow. While the radioactive material is not harmful to people, it is illegal in certain countries due to necessary restrictions with storage and removal.

Photoelectric smoke detectors, also known as optical or photo-optical, use a light stream to detect physical debris or particles in the air that occur with fire or the starting of one.

Like the dual–technology motion detectors, dual smoke detectors combine technology from both ionization and photoelectric smoke detectors. The USFA encourages home and business owners to have one of each type of former smoke detector in applicable rooms or dual smoke detectors alternatively.

Why is my smoke detector beeping for no reason?

When beeping without reason or cause, the smoke detector indicates that it requires a battery change or is not correctly connected to the overall system. Typically, the reason for the regular beeping is an indication of when the device needs a battery change. Unless placed excessively high, no professional assistance is required, with the solution simply being accessing the device and changing the battery before reinstalling

For more information about our motion or smoke detectors, reach out to A1 Security Cameras today!

Why is my smoke detector beeping for no reason?