AC Transformer. Georgia-Pacific Corporation recommends using a UL listed, 24 Volt transformer with at least 10 Volt-Amps of power per dispenser. The power supply output cord is intended to route through the mounting wall of the dispenser. This is a low voltage, energy limited circuit, similar to those used for thermostats, telephones, security systems, or doorbells. In these applications, there is no requirement for an electrical box or strain relief where the wire exits the wall.