I do not know if this is the Right place for me to Post this but because Ring Doorbell is used with SmartPhones I thought I would Ask. I know Ring Doorbell 1. needs 16 Volts or 24 Volts at 20 V/A to be Hardwired in. And the same is for Ring Doorbell 2. as well. But Ring Doorbell Pro. needs 16 Volts or 24 Volts but Says 20 V/A to 30 V/A to be Hardwired in. So if Ring Doorbell Pro. can Run on 20 V/A then why do they Say or 30 V/A?