Anyone here have experience with PIR sensors?
What’s your question? Spit it out man. 
I did a project some time ago that used a PIR to trigger turning on a LED strip (just simple white pixels) when someone walked into an area.
Thats exactly what im trying to do my issue is that the PIR always shows 1 and i cant figure out why. So the LED strip always stays on 
I’ve got a nano and a pir sensor controlling the lights in my workshop. Can’t remember if I even saved the code though…
Have you tried the adjusters on the sensor?
I have a bunch of issues with PIR and EMI. Mostly, you need to either separate the sensor from the micro by a lot, or do some advanced electronics work to reduce the noise generated. I’m using one with a Photon separated by about 15 inches of cabling, and it’s not perfect. The adafruit one is terrible for this. Not sure if others might be better, but I have only really seen two designs out there that look significantly different. My case is extra bad in that I’m using a 433 mhz radio, which activates the sensor reliably every time the radio turns on and off.
There are mechanisms you can use to reduce the noise getting to the sensor. Sorry, I’m not electrically versed enough to help much. My solutions tend to be move it farther away and put lockout controls in code to ignore the sensor when I know EMI is going to turn it on.
Ive tried moving the potentiometers around but no chance. Im using like 6" of wire between the sensor and the nano thou.
If it’s the one that has the dual head (looks like eyes to me) and is a knockoff if the parallax sensor then yes. I had similar issues. These are super cheap but addition to the code found online it requires a an additional periodic reset in the void loop to keep it running else it returns a 1 or zero (can’t remember). I use these for my robotics class to keep costs down. They are fairly accurate if acoustic noise is low and pretty accurate accurate (within a half inch margin).
It this onemissing/deleted image from Google+
If i cant get this to work im just gonna switch to an ultrasound sensor to detect when a person walks by
Can you use like 36" of wire? Maybe add a small capacitor inline to help filter some of the noise?
Correction. The one I use is the ultra sound one not the PIR
Thats what came to mind when you said it looked like a pair or eyes lol
Lol yup… it’s got a shorter range, it’s about 2ft maybe more depending on the object
One of our sketches in the class I teach is a mini alarm system with IR remote for the arm and disarm. It you interested I can paste it here
I really just need a way for the sensor to detect when a person walks by to turn the LEDs on and dim them down when the person is gone
I wasn’t aware of noise issues with these and might have blindly lucked out because I think there was about 6 feet between the PIR and the controller in my project.
Try some distance, and then see if it’s related to some activity. Like I said about mine, it was specific to noise from the network chip.
Also, like, is it ever low? Or only ever high? Can you get it to work at all? Which PIR are you using. Some I have seen are active low devices, and need pullups, and some are active high without pullup or pulldown.
EMI would be intermittent, not constant for this device. It would be related to something that causes spikes in power to some peripheral, or a bad ground, that sort of thing. It shouldn’t be always.
I purchased one from Adafruit which was doing the same thing. They replaced it for me for free and works fine now.
I did a PIR sensor-triggered LED installation and had maybe 10’ of twisted pair (from CAT5 cable) from the sensor to the Arduino. It was very reliable. I have code if you still need it but it’s nothing special.