Patent attributes
An electrical panelboard enclosure includes a primary service panel configured to receive power from a main power source and an alternate power source, an alternate power source connector array, and a distribution panel that delivers main or alternate power to subsidiary load circuits. A service transfer switch unit includes a main power breaker and an alternate power breaker having mutually interlocked toggle switches for respectively activating/deactivating the main and alternate power. The panelboard enclosure further includes an arrangement in which the primary service panel, the distribution panel, the alternate power source connector array and the service transfer switch are part of an installable panelboard assembly that is mountable as a unit within the panelboard enclosure.