12V-3A power supply can wire the building and access control at the same time?
DC12V3A power, theoretically can instantly reach 3A, but there are about 1.2 A to 1.6 A current in general, and building intercom system current is not so low, so we suggest install them separately.
According to my personal experience, DC12V3A access control power supply just consider a access control system and the current voltage for a door electricity only. The other external systems is not including, so we suggested that do not used it with multiple systems or multiple devices.
Building 12V-3A power supply also suggested that don't wire other system equipment.Avoid excessive current burn out the power supply.