I'm pretty new to this, but I recently purchased an arduino, hoping to connect it to my garage door and open it when i signal it to. I have found many diagrams online, but one that I decided on is this:
View attachment 64436
the arduino outputs 5v and a 40 mA current from the digital pin, and I will connect the relay to the 5v power source from the board as well. I found a relay I want to get, here:
https://www.radioshack.com/product/index.jsp?productId=2062480
As you can see, its a 5v relay. the contact capacity is 24 vdc which is what i need, coil current is 90mA, and the coil resistance is 55 ohm. I think this should be fine to open the garage door.
I bought a 1n4148 diode whose datasheet can be found here:
https://www.electro-tech-online.com/custompdfs/2012/05/1N4148_1N4448.pdf
and a 2n3904 transistor whose datasheet can be found here:
https://www.electro-tech-online.com/custompdfs/2012/05/2N3904.pdf
I bought these as this is what the writer of the first blog with the diagram suggested.
Instead of just hooking it up as his diagram says, I want to know why he picked each part, and I am a beginner at this. Can someone help me out?
View attachment 64436
the arduino outputs 5v and a 40 mA current from the digital pin, and I will connect the relay to the 5v power source from the board as well. I found a relay I want to get, here:
https://www.radioshack.com/product/index.jsp?productId=2062480
As you can see, its a 5v relay. the contact capacity is 24 vdc which is what i need, coil current is 90mA, and the coil resistance is 55 ohm. I think this should be fine to open the garage door.
I bought a 1n4148 diode whose datasheet can be found here:
https://www.electro-tech-online.com/custompdfs/2012/05/1N4148_1N4448.pdf
and a 2n3904 transistor whose datasheet can be found here:
https://www.electro-tech-online.com/custompdfs/2012/05/2N3904.pdf
I bought these as this is what the writer of the first blog with the diagram suggested.
Instead of just hooking it up as his diagram says, I want to know why he picked each part, and I am a beginner at this. Can someone help me out?