PIR motion sensor bizarre behavior

[Anker]

I just bought a PIR motion sensor and it has some really bizarre behavior.

Rather than switching on and off depending on whether it sees motion is switches back and forth at a regular basis. It is on for about 1.5 seconds and then off for about the same time. Every second time its on the time is longer, 6 seconds if it doesn't see any motion, shorter if it has seen motion. The consistency is really bad, what I described is just the average behavior.

It is a bad one? They are simple enough to hook up to a digital sensor input and I have the power polarity right.

Thanks/Anker

[adafruit]

did you check out the PIR sensor tutorial?

[Anker]

did you check out the PIR sensor tutorial?

I read it several times. The observed behavior doens't match the behavior described in the tutorial.

Anker

[franklin97355]

Perhaps you should call tech support on Monday.

[adafruit]

theres no phone tech support. if you're sure its malfunctioning, not bad power, you can email support@adafruit to get a replacement. give this forum link as ref.

[Len17]

Wii Controllers

Close, but no banned. Should have advertised "SNES controller ports".

[bmco2n]

Hi Folks,
> I looked at the forum on PIR usage and when I saw one with the same problem
> I'm having, the victim was advised to contact support. So here I am,
> I > bought two Adafruit PIRs and two Radio Shack PIRs and, being aware that
> their +,out and gnd contacts are different, I adjusted accordingly. What I
> am trying to do is to have the ONO type out the time of a PIR event and both
> my millis time and RTClib time work fine in the sketch. But the PIRs fire
> spontaneously to digital pin 2 about once every two minutes and much more often at times.
> I read > the tutorial very thoroughly and the same thing happens when I hook up the
> PIRs to the breadboard according to instructions. I'm having this problem
> with all four PIRs, no matter how I adjust the little pot on the ada.
> Grounding everywhere doesn't work. Placing a 10K resistor between #2 and the output doesn't work.
Because of the breadboard behavior, the > unwanted blinks must originate within the PIR itself, not the ONO or the
> datalogger.
> In the tutorial I watched the video on PIR activation of a camera and
> reading more by this guy, I see cryptic remarks about jumpers on the PIR
> board, but no details.
> Any advice would be much appreciated.
> Cheers,

[adafruit_support_bill]

So, if I understand correctly, you have 4 sensors from 2 diffrerent sources that all exhibit the same behavior?

Are you sure that they are no picking up movement from somewhere? Maybe even through a window? They do have a pretty wide field (110 degrees for the Adafruit model).

[bmco2n]

Hi Teach,

Sorry for the delay. I was checking on "PIR behavior", not "PIR bizarre behavior" This happens when the PIR is under two layers of thick black cloth or in a closed box, which eliminates spurious waves of humidity or air density. It happens when I change locations.

[adafruit_support_bill]

It happens when I change locations

Interesting. Are these outdoor locations? The devices respond to changes in heat sources within their field of view. If the black cloth or box are being warmed by the sun, the 'hot spots' would be changing when you move the box.

[bmco2n]

Greetings:
I think I've found a large part of the answer and I'm posting it for anyone else running into the same problem of spontaneous firing of the PIR output. The PIR enclosed in a black plastic project box produced several "events" until I turned off the halogen and fluorescent desk lights close by. Now, there was only one signal appearing within an hour of inactivity, which is OK for my purposes. Turning the lights back on one at a time brought back the "events" equally; that is, it didn't matter which light was turned on first. Once the "events" started, shutting the lamps off again was not so effective in the short run, but shutting off the surge protector powering the lamps was. I haven't tried shut-off with the other 3 PIRs, but I'm sure they will show the same. I'll experiment with a "sacrifice" PIR to see if a jumper on its PCB might solve the problem. In any case, my project involves all night stints with the lights off.

The other locations I was talking about were inside the house, where firing of the PIR continued from a battery powered breadboard, but in proximity to a halogen lamp --or was it a decrepit electrical system in a 60 year old tract house? However, my work shed where the problem first arose was recently re-wired, including a new ground post. I didn't check outside, away from electricity, but plan to. I live in a desert climate with low humidity, for what that's worth. Static electricity floats around and occasionally, I have to ground my wrist just to type on my laptop.posting.php?mode=edit&f=24&p=112734#

Cheers,