Thanks for the reply Lefty but i am still a little fuzzy about some things. I created the circut by reviewing some similar project online but i really dont understand how it works or why we put things where we did. I attached this pic to help our discussion.
So in the pic Number 1 is one side of the coil and gets the signal from the arduino. I believe the signal is 5vdc? The signal comes out of the Arduino, through the resistor, through the Transistor and onto the #1 side of the coil in the relay where there is also a diode connected.
So number 2 in the pic is the other side of the coil and it is connected to 12vdc and the other side of the diode.
Number 3 is connected to ground of the 12vdc.
Number 4 is not connected to anything
Number 5 is connected to the Ground side of my lights where the hot side of my lights are connected to 12vdc. (the other 2 wires coming from the lights wire are not connted to anything, i just used a old wire i had
Okay... here are my questions...
- Since #2 of the coil is connected directly to 12V+ then is the signal from the arduino really connecting the other side of the coil to the ground side?
- Why does the #2 side of the coil have to be hooked up with a diode and not just directly connected to the 12v+? I understand that the diode keeps a surge from getting to my ATmega but not really how.
- Why are the transistor and resistor needed and how do i figure what values for these componets? If the amps I will draw change will these values also need to change?
- So if i need a relay and the item I need to turn on is 12v and will draw around 260 mA then I need a 12v relay rated at at least around .5 amps???
- So really simply what I believe is happening is that the lights are hooked up to 12v+ and when the relay is tripped it provides the ground side of the connection for the lights to work?
Any other tips or suggestions on what relay I should use for my circut are welcomed... Anyting else you think i may need to know is also appreciated and valued...
PS - how do i insert an image?