I building a generic panel with an arduino, but i would lire to now If it is better to use an external power supply for the panel ? And if yes it power ?
I am not sure what design it is that you are following, it does not look like one of Karl's from the image you provided and you did not provide the schematic. The advice I provided is only applicable when the required voltage is the 5 VDC that the Arduino can put out for limited usage. They do make those power supplies in other voltages if what is being specified is something else.
As I understand it the 5 VDC that you can get from the Arduino itself has limited capacity so it is best to use an external power supply if there is going to be much of a load, just be sure that you use a common grounds for everything. I found an example in Karl's wiring diagrams with this one, look at the lower left to see where the power supply is shown and what it connects to:
The power supplies are widely available on eBay and Amazon. You will want one that has screw terminals for the connections, most are built with standard connectors for use with electronic components. A good example off of eBay is:
I am not sure what design it is that you are following, it does not look like one of Karl's from the image you provided and you did not provide the schematic. The advice I provided is only applicable when the required voltage is the 5 VDC that the Arduino can put out for limited usage. They do make those power supplies in other voltages if what is being specified is something else.
Yes thanks for you'r reply !
I ask the question because on the AP panel building, I didn't see the external power !
And it's a generic panel, for VHF, AP, and switch
As I understand it the 5 VDC that you can get from the Arduino itself has limited capacity so it is best to use an external power supply if there is going to be much of a load, just be sure that you use a common grounds for everything. I found an example in Karl's wiring diagrams with this one, look at the lower left to see where the power supply is shown and what it connects to:
https://fc7bd489-a39c-4f89-b83d-6e26098182dc.filesusr.com/ugd/031b6b_310a6344026f48b3b3bbb1a0990c07d7.pdf
The power supplies are widely available on eBay and Amazon. You will want one that has screw terminals for the connections, most are built with standard connectors for use with electronic components. A good example off of eBay is:
I hope that is helpful.