Capacitive measuring system with automatic calibration

摘要: In a device for continuously monitoring the characteristics of moving filament, such as denier an extended synthetic yarn, by passing filament through capacitive sensor to develop electrical signal representing absolute measurement with reference prescribed datum, problem drift arising from contamination is obviated developing compensating signals be combined signal. The are digitally formed and stored, thereby eliminating in themselves. developed auto-calibration circuit, including auto-zero circuit auto-gain which receives sensor. While vacant, counts clock pulses generate digital output, converts output into analog varying count, detects comparison between input signal, stops pulse count at zero value when detected. Then, applies unbalanced drive sensor, varies gain output. gain-adjusted standardized