Step 4: Testing your PIR

Once you have your PIR wired up its a good idea to do a simple test to verify that it works the way you expect. This test is also good for range testing. Simply connect 3-4 alkaline batteries (make sure you have more than 3.5VDC out but less than 6V by checking with your multimeter!) and connect ground to the - pin on your PIR. Power goes to the + pin. Then connect a basic red LED (red LEDs have lower forward voltages than green or blue so they work better with only the 3.3v output) and a 220 ohm resistor (any value from 100 ohm to 1.0K ohm will do fine) to the out pin as shown. Of course, the LED and resistor can swap locations as long as the LED is oriented connection and connects between out and ground

Now when the PIR detects motion, the output pin will go "high" to 3.3V and light up the LED!

Once you have the breadboard wired up, insert batteries and wait 30-60 seconds for the PIR to 'stabilize'. During that time the LED may blink a little. Wait until the LED is off and then move around in front of it, waving a hand, etc, to see the LED light up!
<p>you bought this for 10$ <a href="http://www.adafruit.com/index.php?main_page=product_info&cPath=35&products_id=189" rel="nofollow">at the Adafruit shop</a> i bought it for about 1.5$ in my country</p>
<p>its not working for me. when i plug everything in and upload the sketch the led comes on and stays on. in the serial monitor it says motion detected. my pir does not have a jumper on the back but it does have three pads. there is 2 pots on it and i tried adjusting them but it didnt seem to help. i got the pir on ebay (http://tinyurl.com/led58rm) if any one can help that would be great</p>
<p>Somewhat similar problem - My sensor detects even there is NO movement. So I changed the pots so that it lowers sensitivity. no help.</p>
<p>Hey, did you find a solution? I have the exact same problem. No matter what tutorial I follow, it always ends up staying at GPIO = HIGH. As in, it is always detecting movement, even though nothing is moving near it.</p>
<p>what worked for me is to make sure my ground was also connected to the arduino. the arduino and pir have to have a common ground.</p>
<p>I have a small trick - If I wave the tip of the screwdriver in between the potentiometers slightly -then I see some motion detected activity. That's not acceptable -but it works for my demo purposes.</p>
<p>In the data sheet the pins you have marked are used to set the trigger in either single or repeat modes. I tried using the system in single trigger mode by soldering the 1st and 2nd pins but it seemed to heat up the system. I then soldered the 2nd and 3rd pins(Circled in Red) and it worked all right.</p>
<p>ok i may try soldering them together and see what happens. :) </p>
Same problem and sensor can only get it to turn off after a minute under a box.
<p>how can i detect the written text or data using motion sensor? Or is there any sensor to serve the purpose of recording the text written</p>
<p>The 'resolution' of the sensor/ lens combo here is WAY too low for what you need. It's pyroelectric so detects thermal energy NOT. Your needs won't be served by a simple electronics project, you'll need a good lens, a great sensor, loads of light and a processor to handle all the data and recognise text. A modern smartphone can do it in real time and even translate it to another language but that costs a lot more than a &pound;1 PIR sensor, an LED and a few wires :)</p>
<p>Sorry *NOT light* that should read.</p>
<p>The 'resolution' of the sensor/ lens combo here is WAY too low for what you need. It's pyroelectric so detects thermal energy NOT. Your needs won't be served by a simple electronics project, you'll need a good lens, a great sensor, loads of light and a processor to handle all the data and recognise text. A modern smartphone can do it in real time and even translate it to another language but that costs a lot more than a &pound;1 PIR sensor, an LED and a few wires :)</p>
<p>would u like to send me the complete instruction of your project my email niazmarshed@gmail.com</p>
<p>Can PIR sensors make the distinction between sizes of objects? Ie Could it tell if it was water or a solid going past it. Thanks.</p>
<p>I used the PIR sensor to light on led lights at night if I need to go to my kitchen for some water or the toilet without switching on the normal lights. I connected the PIR sensor to an arduino mini (5v) with a light sensor and 2 leds. The light sensor stops the leds being turned on in daylight. I powered it all with an old nokia mobile charger. Really usefull project.</p>
<p>would u like to send me the complete instruction of your project my email address is nnn9452@gmail.com</p>
<p>Hey Keep27,</p><p>I want to do something similar with two PIR sensors and a daylight sensor. My project will be modifying a 12v camper porch light with this idea. I will be using a 12v LED bulb in place of the incandescent. Do you have any links you could share with me so I can learn how to do this? My concern is the 12v supply and these sensors are saying 5v. So I need a regulator to step this down I suspect. I continue my search for a good source for a diagram on how a circuit like this could be wired up, any help is appreciated.</p>
<p>Ah looks like my best bet is to use a transistor to switch the 12v on and off to the light. Next thing I need to figure out is how to add a light sensor in the mix.</p>
<p>Hi crazytimmy. Normally you would use some sort of voltage regulator as I understand it. I salvaged an LM 1117adj from an old router in a different project which I'm also going to connect to a 12V lamp output. Normally people suggest using the LM7805 like in this link: <a href="http://electronics.stackexchange.com/questions/109039/reducing-12v-to-5v" rel="nofollow">http://electronics.stackexchange.com/questions/109...</a> but if you are going to use an arduino mini pro or the equivalent to control the PIR sensors and lightsensor, you can just connect the 12v to raw on the arduino (12V is the max.), gnd to gnd and it will supply an 5v output (unless you have the 3.3 version). As long as you don't exceed the max current of the arduino I don't think you will have a problem.</p>
Do you have an instructable of how to drive a 3v relay module with a PIR with no controller? I have tried but it appears the PIR does not supply enough voltage.
<p>hi i am using PIR for last 2 months..Now i measured the output voltage and found it is 3.1 volt. (u said its 3.3v) Is my PIR is dead...or is working fine.? plz help </p>
<p>Its fine. May be it is due to movement sense it may very</p>
<p>MY PIR sensor is being detecting continuously even with movement. What to do?</p>
<p>Hello, can anybody please help me with this? I was wondering if there was some sort of filter that I could place in front of the pir module, that would filter out any low temperature objects and only allow high temperatures to trigger the sensor (body heat). I plan to mount the sensor on a rotating turret, and when it spins I don't want the sensors to be triggered by the moving background (walls, bookshelves, etc.) thanks.</p>
<p>Hey! can the PIR sensor also detect a bird?</p>
how to if i want used 3 PIR for the sensor?
<p>I have python code that monitors multiple sensors on my page.</p><p>http://tigermountainsprings.net/wp/index.php/6-pir-infrared-sensors-and-the-coop/</p>
<p>please how can i connect it to a loud alarm and an halogen bulb?</p>
<p>Can i adjust the range to be 0.5 feet not 20 ? or it's fixed .</p>
<p>What does it mean if the LED is flashing at a very regular interval? Almost like it's on a timer? It's not random. </p>
<p>Excellent tutorial!!</p><p>Hats-off</p>
<p>If still required, Pictures in Step 1 is from the &quot;Infrared Parts Manual&quot; by &quot;GLOLAB corporation&quot;. Hope this helps :)</p><p>http://www.bucek.name/pdf/re200b.pdf</p>
<p>If you want to make your own wireless PIR sensor, try out MySensors motion sensor example:<br><a href="http://www.mysensors.org/build/motion" rel="nofollow">http://www.mysensors.org/build/motion</a></p><p>Arduino library on Github:<br><a href="https://github.com/mysensors/" rel="nofollow">https://github.com/mysensors/</a></p>
<p>How to connect two PIR sensor in one circuit which connected with one light??? If i cross either of the sensor means the single light which is connected to the circuit should glow.</p>
<p>Very nice tutorial! Just want to share this place where you can get the HC-SR501 PIR sensor for cheap: <a href="http://voltatek.com/en/sensors/69-motion-sensor-module-hc-sr501-pyroelectric-ir-infrared-adjustable.html" rel="nofollow"> http://voltatek.com/en/sensors/69-motion-sensor-m...</a></p>
When testing, is the resistor necessary?
<p>..the resistor is needed for testing with LED (to limit the current)</p>
what if i would like to turn on a relay when trigger? <br> <br>thanks! <br>marC:)
<p>buy this </p><p><a href="http://www.ebay.ca/itm/310566336050?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649" rel="nofollow">http://www.ebay.ca/itm/310566336050?ssPageName=STR...</a><br><br>very easy to use</p>
What would i have to do so that it alerts my phone when motion is detected?
<p>gsm shield and a activated sim card and some electronic basic supply</p>
How much current can the module deliver to the output? <br> <br>Great write up. Thanks.
<p>not really, he copy and pasted it from the website he linked.</p>
Hey there guys, i would just like to know does the PIR motion works with other programming such as C programming and such. Another thing is, is it possible to do this: <br>When sensor detects, LED lights up <br>When sensor x detect, LED would dim instead of off. <br>Thanks. Your reply would be highly appreciated. <br>
<p>I actually just posted an Instructable recently that essentially does what you are asking. Only thing you would have to change in the code is the PWM value in the analogWrite() function from 0 (which is totally off) to 50 or so (which would make the LED shine dimly). </p>
WOW! Thanks for this tutorial!! I love it! Thanks for doing this!!! 11 thumbs out of 10!!! :-) <br>
Hi, <br>I would like to know if PIR sensor can tell me that the person in range is moving toward to the left or right? Is it possible or I need something else to detect? <br> <br>Thanks!

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