Method and apparatus for providing uninterruptible power

An uninterruptible power supply including a back-up power source, converter circuitry coupled to the output and to the backup power source to provide the output power from the input power and the backup power, a contactor having an open state and a closed state and a contactor control circuit to provide an output voltage to control an operational state of the contactor, the contactor control circuit having a boost converter receiving an input DC voltage and providing an output voltage having a first voltage level to control the contactor to switch from the open state to the closed state and to provide a second output voltage having a second voltage level to maintain the contactor in the closed state, the converter circuitry including an input circuit coupled through the contactor to the input of the UPS to receive input power and coupled to the back-up power source to receive back up power and configured to selectively provide DC power derived from the input power and the back-up power and an output circuit coupled to the input circuit to receive the DC power, and configured to provide AC power, derived from the DC power, at the output of the UPS.