I want to connect a 240 V PIR motion detector directly to my Raspberry Pi 3.
Inside its plastic case I found two PCBs. One is the power supply board which has a 24 VDC relay, an S9013 NPN transistor, some blue resistors, two small zener diodes and one bigger one, a big red film capacitor (CBB22/630V334J), a smaller one (CBB22/630V223J), a gray film capacitor (222/1200V), four 1N4007 diodes, two electrolytic caps (220 μF/35V, 100 μF/25V), one small ceramic capacitor, two big gray resistors (?) and three wires (red, blue, and brown).
The other board contains the PIR sensor, an S9013 NPN transistor, a lot of blue resistors (?), a UTC324D IC, five electrolytic caps (1 μF/50v, 10 μF/50V, 100 μF/16v, 100 μF/25V, 47 μF/25V), four small ceramic capacitors, three Zener diodes, three potentiometers for adjusting SENS, TIME, and LUX and a photoresistor (which I removed for another purpose and I can't find it, but I think it works without it).
The board with the PIR sensor is connected to the power supply board with three wires. How I should connect these three wires to my Raspberry Pi 3 in order to get the PIR sensor working? Do I have to remove something from the PCB? Is it going to work on 3.3 V as it is? The UTC324D datasheet says that it can work with supply voltages between 3-32 VDC so this is not a problem.
If I can't connect it to my Raspberry Pi, can you tell me how I can make this work on 12 V? I have seen a tutorial about wiring an external motion detector to 12 V, but the author of the article had a 4-pin board and I don't know how to wire it.