Introduction: Make an Simple Motion Sensor Light! (PIR)

Picture of Make an Simple Motion Sensor Light! (PIR)

Make an Small & Simple Motion Sensing Light with Less Hassle and Less Components.

A Beginner Could Also Make This.

A Simple Understanding of how transistor works and knowledge of Anode and Cathode is only needed so Make it Tension Free!


I Now Accept Custom Jobs too , Therefore if you have a Design in Mind then I could send you the 
PCB Design for $20.<strong> Send me mail at if you need one. </strong>

Step 1: Gather the Parts

Picture of Gather the Parts

One can Buy Everything Used in this Project from Ebay.

While i Get most of the Things from my Local Electronics & Robotics Store so i don't buy from ebay.

Anyways , Here is the List of Parts which are Needed :

1) PIR Motion Sensor. ( Main Part , i am using HC-SR501 )

Note that every PIR Manufacturer might have a Different Pinout. So Please confirm the Pinout of PIR Before Performing this Project. [ My PIR Had Pinout - VCC | Output | Ground || (From Back Left to Right Direction) ]

2) BC547 NPN Transistor

3) (4 Pcs.) White 5mm Leds

4) Small Copper Board

5) 2 Pin Screw Terminal

6) 3 Pin Right Angle Header

Step 2: Circuit

Picture of Circuit

A Simple Circuit , Controlled by two major Things.

1) BC547 Transistor

2) PIR Motion Sensor

This Can be Done on Perfboard too.

Explanation :

When PIR Sensor sense any Human interference or ir Light running @ 38KHz

then it's Output Pin Become from LOW to HIGH which result in 3.3v Supply in Output Pin,So We Would be using that output pin to switch the transistor on and off which will lead to On and off of leds too.

Leds are Connected in Series So that they would consume all 12v Supply once switched and which would not lead to burning.

Note : Only Supply 12v , If Voltage Greater than this than it will lead to burning of leds.

and PIR has an in-built Regulator which will accept 12v.

Step 3: Breadboard Circuit

Picture of Breadboard Circuit

For Those who want to build it on a Breadboard.

Step 4: Eagle PCB File.

Just Print the Pdf Attached.

and i will be using the Toner Transfer Method.

it would be your choice which method you will choose because end result would be same.

Step 5: Transfer the Artwork

Picture of Transfer the Artwork

Just Press Hardly with an iron with full High Temperature Dial for 4-5 mins.

After this immediately dip into Water and Gently Rub the paper on pcb with your thumb.

The Artwork must have Attached to Pcb.

Otherwise if traces are broken then try again.

Step 6: Etch It!

Picture of Etch It!

Now put the PCB in Ferric Chloride.

You may use HCL+ Hydrogen Perxide too.

Step 7: Drill Holes.

Picture of Drill Holes.

I use my Hand Drill to drill holes.

it was just useless drill bought from ebay for 2$ , Got it's Spring loose after making 15 pcb's

So, I am switching to a motorized drill for my future projects. ;)

Step 8: Solder Screw Terminal

Picture of Solder Screw Terminal

Make sure to drill with 1mm bit for this because they have a kind of broad legs.

Step 9: Solder Right Angle Header

Picture of Solder Right Angle Header

Step 10: Solder Leds.

Picture of Solder Leds.

I Use white because 3v x 4 leds = 12v

which will not burn the leds.

and make sure the Anode and Cathodes of leds.

Step 11: Solder the Transistor

Picture of Solder the Transistor

Be sure to face the flat side of transistor towards leds.

Step 12: Solder the PIR

Picture of Solder the PIR

Till now you might have known that why i soldered the right angle header.

it was soldered to position it motion sensing part towards our self.

Step 13: Power It.

Picture of Power It.

Now power it with 12v.

Give the sensor a warm-up time of 10-60 Sec.

And test it.


kacool (author)2017-09-24


Can you please help me with the circuit diagram,As

I have 3.7V lithium ion battery and i want to glow 4 v led strip.

So which circuit would be good enough so that i can receive full illumination from led strip.

and in some lights there is on function coming , that if there is no motion than the brightness of led light decreases but if suddenly any motion is detected than it illuminates to full its full brightness.

So please let me know ASAP.

Nice Instructable.

thank you

Dcomp (author)2017-07-31

Hi !!

I have a question does this whole project work on any home appliance like light,fan,etc. If we want to make like that type what should i do ??

AbhishekJ31 (author)2016-10-11

Awesome project....
Helped a lot...

TelephoneT (author)2016-03-20

Dear instructableinstructors,

I really enjoy reading all your posts. I have a question. I have build the strangest 9V solar panel all by myself (18 cells of 0.5V ) and it has no diodes or anything attached yet. How would I be able to actually use this solar panel in combination with pir motion sensors and 10W led lights to create a soft sheen glow on the path leading to the house when you pass the pir sensors. I have the solar panel idle for 3 years now. I have 5 pir sensors and I have ordered 50 of the 1N4007 diodes, rechargable 1.2V batteries, nothing else yet. What would I need to make this work?

The panel is made of the following cells: I managed to not break 18 and put these together inside glass box with mains type wire comming out the back) 100pcs 3.9 - 4W 0.5V solar cells polycrystalline 156x156mm with 2 busbar, 17-17% efficiency.

Inno66 (author)TelephoneT2016-05-30

hi, i think you can first build complete sensor circuit using PIR and bc547 and just put couple of LEDs in series at your output instead of one, then you use your solar power as your supply (find a way to get 2 output terminals into sensor circuit) ,since its 9v youll probally have to not put any resistor in series with LEDs as they are many....but if so, say 10 can put variable to 70ohm

LobnaK1 (author)2016-05-05

Hi guys , i have a question i am doing my graduation project using arduino and i want to make a ball fall out of an opening with a motor , any ideas? thanks..

Abhi909 (author)2016-01-31

great project

can i place your project on my website.

i'm working on a website which is related to electrical projects.

i also mention your name, link and other info.

plz reply

Ayush Sharma (author)Abhi9092016-02-22

Hello Abhi,

Let me know your Website url.

I Would Love to Visit it.

Ayush Sharma (author)Abhi9092016-02-10

Sure :)

crazytimmy (author)2016-02-22

Love the write up, awesome pictures/diagrams easy to read and understand (I think LOL)

I am doing a project that modifies this camper porch light:

and this LED Bulb:

and turn it into a motion sense activated light. I should be able to just put it in place of your LED's (as its a 12v LED) but I would also like to have two motions (1 on either side of the porch light) and a daylight sensor so it only works at night.

Not sure if I will have issues with that light as there are alot more LED's then yours but it says its a 12v LED light. Would you be able to point me in the direction of a wire diagram or breadboard image of the circuit or perhaps if you have time to create one for me? Your images are very easy to understand. Is there a program you used for designing before physically building the circuit?

Thanks for taking the time to read this long question, any help is appreciated.

YadvendraM (author)2016-01-22

Can i use it for bathroom mirror?
I mean for how long the lights will keep on?

Ayush Sharma (author)YadvendraM2016-01-22

You can Adjust the Oboard timmer from 5Seconds to 3 Minutes. ( After there is no motion sensed) If you are Getting Detected for longer periods ( i.e more than 3mins. ) then the Timmer will get Skipped by default and light will be on until and unless you leave your bathroom.

OnBoard Timmer*** ^

nnthx (author)2015-12-02

what do you mean by powering it with a 12v?? please reply, urgent

nonethx50 (author)2015-11-06

I love this idea and Im actually going to use it for a project but can someone tell me of it really lights up?

Ayush Sharma (author)nonethx502015-11-11

It Does ...

ShashiY (author)2015-09-25

how to use it with ac appliances like fan,light. plzzz help

Ayush Sharma (author)ShashiY2015-09-26

Please see my "Simple Motion sensor Relay Board" Instructable . It deals with switching AC Appliances.
I hope this helps! :)

achik00 (author)2015-08-10

is this will work if using 5v? please reply, urgent

Ayush Sharma (author)achik002015-08-10

Pcb and circuit is designed for 12v use but you can modify by replacing those 4 leds with a 100Ohm Resistor and 1 White led . Rest Every thing would be same.

I Hope this Helps.

charlessenf-gm (author)2015-05-19

I would like to be able to use such a circuit - but to control a/c devices (light bulbs, etc. Might i simply replace the LEDs with a 12vdc coil relay? Or would that draw too many 'amps?'

dad45 (author)charlessenf-gm2015-06-14

Good easy project here. I used a PIR, transistor and relay setup like this for triggering a halloween display when people were detected. The simple circuit like this works, however depending on the PIR and the movement of the people you often get many pulses on the PIR output which then makes the relay cycle too much. Not much of problem for a halloween display. So with this simple circuit your a/c devices may go on/off too quickly. One method to correct that is with software and a microcontroller. Of course now this simple circuit has become more complex.

You can See my next motion sensor instructable on Relay + Motion Sensor

Yes, you Could use Relay instead of leds.
Just make sure there is a transistor.

Ayush Sharma (author)2015-05-29

It is sad that i coudn't enter the Home Automation Contest Because This was Published just a day before....

Anyways thanks Everybody for making this hit...

wannabemadsci (author)2015-05-14

Neat instructable. In the Step 2 schematic I believe your LEDs are shown reversed. Electron flow would be out of GND, 'against' the transistor emitter 'arrowhead' and flow into the LEDs' cathode (flat line) and 'against' the 'arrow' of the LED symbol.

Ayush Sharma has updated the schematic so the one in the instructable is now correct. Please don't think that I am saying the present schematic needs to be changed. It does not.

dsearfoss (author)wannabemadsci2015-05-23

Ok thanks

dsearfoss (author)wannabemadsci2015-05-18

Wrong diagram is correct as shown

Done. Thanks for Notifying me :)

Thank You ,. Yeah i wanted to correct it first only but i was not getting the time.
I will correct it today.

3366carlos (author)2015-05-14

very nice. without a resistor, you may be dropping too much voltage across Q2,.

dsearfoss (author)3366carlos2015-05-19

The HC-SR501 contains a 1K in series with it's output to protect the chip from overload

Ayush Sharma (author)3366carlos2015-05-15

I suppled 12v and i added 4 leds to fully consume 12v
I hope this would not burn because it means 3v on each led?
Thanks for your comment :)

3366carlos (author)Ayush Sharma2015-05-16

i believe each LED consumes 0.7vdc, so the rest is consumed somewhere else. A resistor would be good to consume the rest (4x0.7 = 2.8V - 0.7 (of Q2) ) = 12-2.1=9.9v. You can verify this by measuring wity your voltmeter across each component. Good job otherwise.

desbromilow (author)3366carlos2015-05-17

3366carlos, the forward voltage of a LED is different for most colours (ie red has a different voltage drop compared to blue, different for white, etc) Part of designing a circuit is to determine the voltage drop (forward voltage) of the LED and then drop the remaining supply voltage across a resistor - your advice about checking is great, or use the datasheet for the LED to determine voltage drop.

Ayush Sharma (author)3366carlos2015-05-16

The Leds i attached was white ones so they consume 3v each led = 12v

Other colors are an different story , the we would need to attach a resistor.

Anyways , Thank you Very Much.

Rand0mUser (author)2015-05-17

Probably easiest to just put an LED plus resistor from the output to ground - those modules always output a regulated 3.3v, whatever the input voltage is.

Also, it's best to use female header on the breadboard as a 'socket', rather than having to permanently solder like that, leaving the pins exposed to a stray bit of wire.

Other than that, nice work!

Ayush Sharma (author)Rand0mUser2015-05-17

I tried the led method you suggested but the current was too low to light an led full. So i had to go with transistor way.
Anyways Thanks

dsearfoss (author)Ayush Sharma2015-05-18

The HC-SR501 contains a 1K in series with it's output to protect the chip from overload

bhimalingam (author)2015-05-18

A good and simple instructable to devlop interest in electronics.

pmshah (author)2015-05-17

I would add an LM317 regulator in constant current mode to keep the brightness constant.

diyexcel (author)2015-05-15

A junior high school students can do better than this

bill.harvey.100 (author)diyexcel2015-05-17

bill.harvey.1000 seconds agoReply

you have nothing good to say, say nothing. I don't see that you have
any Indestructible that is better therefore your comments are without

If you have nothing to add go do something else. Hater gonna hate!

diyexcel (author)2015-05-15

electronic circuit level as it is too bad . The circuit is broken and it is too bad drilling vessels , conclusion is still too poorly qualified

bill.harvey.100 (author)diyexcel2015-05-17

If you have nothing good to say, say nothing. I don't see that you have any Indestructible that is better therefore your comments are without merit. Frankly I find it hard to understand what it is you are trying to say anyway. The guy did pretty good.

Ayush Sharma (author)diyexcel2015-05-15

Instructables is not about discouraging Authors , If you don't Like the The Thing then Don't Comment.
Anyways there would be a reason on featuring my instructable. so please better you stop discouraging people.

dwhite0 (author)2015-05-17

It sure would have been nice to include the power connections to the wiring diagram. Not everyone is an electronic engineer.

Dan White

bill.harvey.100 (author)dwhite02015-05-17

Vcc and Ground are clearly shown. But you have already said that you are not an electrical engineer. This kind of Instructable might be your start.

BurgersBytes (author)2015-05-17

The PIR circuit can actually work with 3 volts and you could still drive 4 bright LED's with that. In fact I have found a PIR circuit that works on one AA battery and drives 4 bright LED's too for about $4.

About This Instructable




Bio: Just a Small Tinkerer ;)
More by Ayush Sharma:Pocket ESP8266 Weather Station [No ThingsSpeak] [Battery Powered]Make an Simple Motion Sensor Theft Alarm! (PIR) (DIY) How to Make ESP8266 Ultra Mini & Simple Relay Home Automation Board
Add instructable to: