Abstract: A power supply for a xenon arc lamp that will automatically shut down if the lamp current is too high, the lamp voltage is too high, or the lamp requires too many trigger pulses to ignite it. Such conditions indicate faults in the lamp itself and should not be operated this way for safety. Lamp-on and end-of-lamp-life indications are provided to the operator for maintenance. The cooling fan power supply must be normal or the lamp will be shut off or not started. In combination, such provide a lamp system that can safely operate at very high powers.