The 24V transformer in the kit is UL listed, double insulated, and equipped with a standard 3 pole NEMA plug intended for mounting into a standard 120V NEMA duplex outlet. The power supply is equipped with a 9' (3m) low voltage outlet cord terminated with a polarized connector for attachment with a mating connector of the battery box power adapter. For warranty purposes, it is required that the power supply must plug into an A/C outlet that is not accessible to the dispenser user. The A/C outlet is usually installed above a dropped ceiling found in most commercial bathroom facilities. If not available, consult a licensed electrical contractor. 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.