Electronic proximity detection system with status indicator

摘要

The proximity detection system uses an external electronic sensor, e.g inductive capacitive or opto-electronic, to influence a presence detector, e.g. an oscillator (1). An edge-sensitive trigger (2) drives a switch, e.g. transistor thyristor or triac, or other indicator (6) to show detector status when a partic. parameter, e.g. sensor distance, exceeds or falls below a preset level. Sensitivity cna be adjusted such that background levels cannot alter detector status.