Power Limiting Methods for Use with Optical Systems in Hazardous Area Locations

摘要

A fiber optic sensor interrogation system with inbuilt passive power limiting capability that provides improved safety performance for use in explosive atmospheres.

主权项

1. In a fiber optic sensor interrogation systems that includes at least a light emitting path for sending interrogation light signals and a light receiving path for receiving returned light signals, a method for enhancing safety by:
a. sending the interrogation light signals from the light emitting path through a circulator/coupler device out into a region of interest to be measured; b. returning backscattered light from the region of interest through the circulator/coupler device into the light receiving path; and c. locating a passive power limiting device after the light emitting path and before the circulator/coupler device.