Functional Devices Relay in a Box Power Series Relays are designed for higher amp commercial or industrial energy management applications. They are solidly engineered and manufactured for long lasting durability and dependability. This series contains a wide variety of enclosed and t‑style relays rated at 20 or 30 amps. It also features the following voltage configurations: 12V,24V AC/DC, 20V, 120‑277V, 208‑277V, 480V AC. Override switches are also available on some models. The relays are BACnet compatible relay devices. They provide a software‑implemented network interface between BACnet client devices and Relay in a Box control and monitoring points.