Abstract: A power control apparatus, particularly for lighting systems such as fluorescent lights. A power variation circuit (16) is provided coup led between a mains electrical input power source and at least one power output to a load (6) such as a lighting system. The power variation device is controllable to vary the power level supplied to the load according to control signals from a digital processing circuit(10). Monitoring circuitry (12, 14) is coupled to the digital processing circuit (10) to provide monitoring signals relating to electrical parameters of the input power source (4) and/or the at least one power output (9). The digital processing circuit (10) is responsive to a condition of the monitoring signals to control the power variation circuit (16) to supply the power output (9) at a first predetermined level for a predetermined time period and thereafter to reduce power output to a second predetermined level.