A power control system includes a first inverter power control system and a second inverter power control system coupled in a parallel configuration with the first inverter power control system. Both first and second inverter power control systems may each include an input configured to receive direct current (DC) power; a DC to alternating current (AC) inverter stage configured to receive the DC power input; an anti-islanding relay coupled to the output of the DC/AC inverter stage; and a transition relay coupled to the anti-islanding relay. The transition relay may be configured to route an output of the inverter power control system between one or more onsite back-up loads and an AC grid. The first inverter power control system may be designated as a master that is configured to control the operation of the second inverter power control system designated as a slave.