The Barrett 4022 Power Supply with built-in charger is designed to provide regulated power to one 4050 Transceiver and one accessory. The 4022 also has provision for a battery backup system in case of mains power failure. The battery backup incorporates a true automatic no-break change over circuit with a battery charging system, which restricts the output to the maximum 13.8 V of the battery.

The Barrett 4022 is a low noise switch mode power supply which delivers 24 V at 18 amps continuously. It supports a mains input supply that can vary from 85 V AC to 264 V AC This combined with the ability of the power supply to operate with a Sealed Lead Acid (SLA) backup battery, makes the 4022 ideal for use in areas where mains voltages vary dramatically and occasionally fail altogether.