PIR Motion Sensor

SEN-08630

• http://www.sparkfun.com/products/8630
• http://bildr.org/2011/06/pir_arduino/

SKU 139624

• http://dx.com/p/ir-infrared-motion-detection-sensor-module-dc-5v-20v-139624
• http://blog.roman-mueller.ch/index.php/2013/01/26/hc-sr501-passive-infrared-sensor-with-arduino/
• http://zygzax.com/2012/11/17/sensor-de-movimiento-pir-hc-sr501/?lang=en

The HC-SR501 Module has three connection pins: +5v, OUT(3.3v) and GND; and two variable resistors for calibration (Ch1 and RL2).

Ch1: With this resistor, we can set the time that the output of the sensor will be active. One of the main limitations of this module is that the minimum time is about 3s. If we change the variable resistor to another of 100K, we can decrease the minimum time to approximately 0.5 s.

RL2: This variable resistor allows us to set the detection range, which could vary betwen 3-7m.