How do you know if your solar panel is working?

Are you talking about the solar panel for the Ring 2 device that costs $49? I’m wondering what you mean by plug? There’s something that gets attached by 2 screws…is that what you mean? I’m trying to figure mine out also. I don’t feel like it’s working but wondering if it has to do with the connection. It would make so much of a difference if the app recognized the device and showed that a solar panel was attached.