Connecting AC adapter to Ring Video Doorbell

I have connected my ring video doorbell (gen 1) to an AC adapter which from memory, puts out 18V and 500mA. I'll attached a photo of the specs. Before I close up the cladding I would like to know how to tell if the AC power source is working if the doorbell actually always used battery and the only the battery icon is displayed. Choose Filed not working to upload images....