The optical power surge protector is a two-fiber port module that has low insertion loss during normal operation, but suppresses an optical power surge quickly (about 100ns) and maintains a preset maximum allowed output power as long as the surge presents. This is achieved by using a detector to tap a small amount of light from the output and feed it into a closed-loop circuit to control an NS variable fiber optical attenuator connected between the light input and output. The maximum output power is manually set by a resistor pot through a screw hole with a range from 200mW to 2W. High maximum output power up to 10W is available through special order. The optical power surge protector provides the ultimate solution for sensor protection. The non-mechanical device has passed the most stringent mil-spec and space flight qualifications and is designed for over 20 years of continuous operation. The module comes with a wall-plug 12V power supply.