user59869: Im in college and our research is about a fingerprint based door lock system.  We really dont have any idea about arduino.  Now we bought arduino mega for our research but I dont know how to connect all 6 solenoid locks to an arduino.  Please help It would be very much appreciated if you answer and it will be very helpful to us. I know there are same research about this in the internet but  i cant find any of these.  If you have any website about this research it would be very helpful.  Thanks 

user57111: To follow up on CrossRoads' suggestion of a power MOSFET circuit, there is more detail on how to do it in an answer over in the Electrical Engineering group. Digikey.com is a great source for components. 
https://electronics.stackexchange.com/questions/29065/how-to-control-a-12v-solenoid-valve-with-a-mosfet

user49295: Supposing the lock you use is a simple solenoid that works with 12V, you should connect them to the output of a relay module, and then connect the Arduino to the module. Like this example here: link.
You will probably want to connect each solenoid to an individual relay, so you can activate each one of them individually. With that in mind you might want to use an 8-channel relay module like DataFiddler recommended. example 
You will need a 12V power supply, and be sure to check the current drawn from your solenoids and see if the power supply can handle it.


59869: <p>Im in college and our research is about a fingerprint based door lock system.  We really dont have any idea about arduino.  Now we bought arduino mega for our research but I dont know how to connect all 6 solenoid locks to an arduino.  Please help It would be very much appreciated if you answer and it will be very helpful to us. I know there are same research about this in the internet but  i cant find any of these.  If you have any website about this research it would be very helpful.  Thanks </p>
 57111: <p>To follow up on CrossRoads' suggestion of a power MOSFET circuit, there is more detail on how to do it in an answer over in the Electrical Engineering group. Digikey.com is a great source for components. </p>

<p><a href="https://electronics.stackexchange.com/questions/29065/how-to-control-a-12v-solenoid-valve-with-a-mosfet">https://electronics.stackexchange.com/questions/29065/how-to-control-a-12v-solenoid-valve-with-a-mosfet</a></p>
 49295: <p>Supposing the lock you use is a simple solenoid that works with 12V, you should connect them to the output of a relay module, and then connect the Arduino to the module. Like this example here: <a href="http://www.arduinotutorialonline.com/2018/05/relay-module-solenoid-door-lock-how-to.html" rel="nofollow noreferrer">link.</a></p>

<p>You will probably want to connect each solenoid to an individual relay, so you can activate each one of them individually. With that in mind you might want to use an 8-channel relay module like <a href="https://arduino.stackexchange.com/users/16780/datafiddler">DataFiddler</a> recommended. <a href="https://rads.stackoverflow.com/amzn/click/com/B00KTELP3I" rel="nofollow noreferrer" rel="nofollow noreferrer">example</a> </p>

<p>You will need a 12V power supply, and be sure to check the current drawn from your solenoids and see if the power supply can handle it.</p>

<p><a href="https://i.stack.imgur.com/mo0ih.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mo0ih.png" alt="enter image description here"></a></p>
