Circuit Newbie here, need help with my PIR Sensor

izaman93

This is the parallax sensor I bought.
http://www.parallax.com/Store/Sensors/ObjectDetection/tabid/176/CategoryID/51/List/0/SortField/0/Level/a/ProductID/83/Default.aspx

On the bottom of the sensor there is +, -, and something labeled as signal

What is signal mean?

Also here is the components I have

Battery Case (3C)
Buzzer 4-20v
and this sensor.

I need to somehow wire this together so that when the infared is tripped on the sensor it causes the buzzer to go off

Thanks! any help would be appreciated

Ron Czapala

Welcome to the forum!

This sensor (and most others sold by Parallax) are designed to work with or be driven by a microcontroller like the Basic Stamp or Propeller.

Look at the the documentation on the product's web page http://www.parallax.com/Portals/0/Downloads/docs/prod/sens/555-28027-PIRSensor-v2.1.pdf

You probably won't be able to drive the buzzer directly because of the current limitations of the pins on the microcontrollers but a simple transistor like the 2N2222 can be used to drive the buzzer.

Jen J.

Here is a KickStart example for the PIR sensor. It may help if you plan on hooking the sensor up to a microcontroller.
https://sites.google.com/site/parallaxinretailstores/home/pir-motion-sensor

kwinn

The signal is the output. It goes high when it detects something and is low otherwise. The + - pins are for power. The sensor can drive small loads directly but you may need a transistor or driver of some kind if your buzzer draws more than a few milliamps.

Ron Czapala

Here is a Parallax YouTube video http://www.youtube.com/user/ParallaxInc#p/u/37/au_C2qT1bVc