Help with the PIR SE-10

Hello all,

I’ve purchased the SE-10 PIR sensor that you can see here
Can you help me identify the +V, GND and Alarm Pin by the back of the sensor?

I’ve connected the sensor to the 5v on Arduino (red), Ground(brown), and AlarmPin(black) but I’m only getting 0, LOW, on serial monitor. It only goes HIGH if I disconnect the alarm pin and because I have a pullup resistor on the same 5v to the pin.

Is this a voltage problem because I’m feeding from de 5v of arduino or could it be bad assembly connections?

Thank you

Well thank you anyway to all, but I found the answer and I will post for everyone interested.
Beside all tutorials you can find on the net about this device, nevermind the colors of the wires because it seems that they can be diferent, so, to prevent wrong connections look at the beginning of the wires on the board and try to find B+ and AL, those will be VCC and Alarm PIN.
And that’s what you need.
By the way, using the 5v from Arduino the detection of the IR is not clean, and I also read that we should use a power supply from 5v to 12v just to have a reliable detection.

If you have any questions please post.


Sorry for the trouble you had, and thanks for letting us know what you found out! I checked a sensor we have in stock, and the cable colors did not match the description on our website. I have changed the website description to match your description.

How are you measuring the noise? I am not sure what the cause of your noise issue is or even if it is normal. Do you have an oscilloscope? Perhaps putting a greater than 50 uF capacitor between the sensor’s power and ground at the sensor board would smooth out the noise, if the power line is to blame.

- Ryan

Hello Ryan,

I made a simple detection test with Arduino, giving +5v to the sensor from the 5v output pin of arduino, and the sensor detects motion even when no movement occurred, but it’s random. If I wave my hand several times in front of the sensor the detection is constant, so, I think the sensor is OK and I’ve been reading on some forums that are more users with the same problem.
I don’t have any noise on my arduino input for sure because I used a pullup to get 5v on it when the sensor is not detecting.
I will now provide a clean external 5v to the sensor to see what’s the behavior. Next step I will give 12v if that fails.

I’ll keep you all posted.


Hello all,

Everything is running good !!!
I’ll post my experience for the one interessed:

  • I am now powering my Arduino from VIN port with 9v. This 9v come from a ATX PSU that is delivering 12v that I’m pulling down to 9v with a voltage regulator, L7809cv, and feeding both Arduino and the PIR sensor. With this voltage rate, the Arduino is working very good and the PIR is sending a nice clean signal to the INPUT without oscillation or floating.

So everything is running GOOD now :slight_smile:
The trick for all using this PIR sensor is to feed it with more than 5v and it will give a stable output.



Thank you for following up and letting us know how you got it to work. I’m glad to hear that everything is working well now.

- Ben