Infra Red Motion Movement Detector

Infra Red Motion Movement Detector

This is an excellent security device, sees infra red heat of intruder in field of view. This is a recent design for a PIR detector; should not be underestimated. Rather than the usual opamps and amplifiers, this kit uses a movement IC. Has PC board mounted Fresnel lens. IC has circuits to turn off detector in day light. Two levels of sensitivity. When tripped an LED indicator lights and a relay is tripped. "Sees" up to 18 feet.


  • L: 3" W: 1-7/8" H: 1-1/2"
  • Operation on 9 or 12 volt battery with very long life.
  • Light sensitivity adj. for day/night use.
  • Exit delay option.
  • Alarm on-time adjustable.
  • Connect a low voltage siren, or relay to switch larger load.

Infra Red Motion Movement Detector Reviews:

  • --> I used it for a cat bell. It works outdoors in snow and ice. The sensivity is excellent to a degree, that I had to narrow the field of view. The assembly instructions are detailed, so I could put it together without making mistakes. I would have liked a bit more info on the usage of the Fresnel optical lens.


  • --> The kit is easy to construct and the PCB clearly marked. The instructions are pretty clear but go into a lot of unnecessary detail which only confuse rather than illuminate. You need to add your own kit enclosure box, siren or light, toggle switch, battery holder, and battery which adds to the cost of the final assembly. If you plan on moving the alarm around, it is important to add a toggle switch so you can shut off the alarm. I added a 555 timer circuit to run for 10 seconds. After 10 seconds the alarm automatically shuts off and resets itself so as not to run down the battery. The kit has three trimpots to control PIR sensitivity, daylight sensitivity, and pulse on-time to adjust the output. I couldn't get the alarm to shut off during daylight in spite of turning the daylight sensitivity trimpot to the least sensitive position. I don't really care, because I want to use it outside at night to frighten pests out of my yard. Last night, it detected a rabbit, a dog, a cat, and a deer. The only disadvantage is its range which is from 18 to 20 feet. So you may plan on assembling more kits to cover a larger area.