INTRINSICALLY SAFE COMMUNICATION AND CONTROL SYSTEM FOR USE IN HAZARDOUS LOCATIONS INCLUDING MONOTORING DEVICE WITH INTRINSICALLY SAFE FLUORESCENT TUBE BACKLIT

An intrinsically safe data acquisition system is disclosed for use in hazardous locations. The system includes a driller's console that itself is intrinsically safe and includes a large LCD monitor, keypad and local CPU. The monitor includes an intrinsically safe backlighting system. The system further includes satellite data acquisition and processing boxes that are also intrinsically safe and that are located within the hazardous area. Each satellite box includes its own CPU and acquires and locally processes signals received from a number of field sensors. The satellite box converts the signals into digital form, and transmits the data via a fiber optic communication channel to a master CPU box located in an unclassified area. A high current intrinsically safe barrier distributes power from the master CPU box to the satellite box for powering all the sensors supported by that satellite box. Another such barrier distributes all the power required by the driller's console.