DC 12V 24V PIR Motion Sensor
There is a small problem with this motion detector and that is that the detector is not sensitive to light.
Usually modules are light sensitive and they can distinguish between day and night.
Fortunately, pin 9 of BISS0001 is reserved for this case.
It is designed so that when the input voltage Vcc on pin 9 is high, the PIR input is enabled and when Vcc is low, the PIR input is disabled (Vcc <0.2 Vdd = disabled).
An LDR (photoresistor) “Trigger Disable Input” can be put between pin 9 and ground to make this happen.

This will be quite enough for darkness or twilight detection but for setting the light intensity you have to replace 100k Ohm with a 1M Ohm potentiometer.
LDR – Light Dependent Resistor
1000 lux bright sun ~ 150R
100 lux daylight ~ 2k ohms
10 lux twilight ~ 10..20k 100..200k
1 lux dark ~ 100k
0 lux ~ 1.0M..10M


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