公开(公告)号：US3879657A

公开(公告)日：1975-04-22

申请号：US42708273

申请日：1973-12-21

Applicant: ECONOMICS LAB

Inventor： NYSTUEN MARCUS I ,  JOHNSON ROGER A

IPC: G01N27/04 ,  G01R27/02 ,  G01R27/22 ,  G01N27/42

CPC classification number: G01R27/22 ,  G01N27/04 ,  G01R27/02

Abstract: Electrical apparatus for reducing the drift in the set point of an electrical bridge type conductivity sensor utilizing a pulse producing circuit (e.g. an astable multivibrator type switching device) to provide an AC voltage of very short duration to the conductivity cell electrodes for minimizing the cumulative polarization thereof. Pulse lengthening circuitry is also provided to assure that the relatively short output pulses from the bridge circuit are of sufficient duration to properly operate apparatus for injecting an additive product into the conductive medium.

Abstract translation: 电气设备，用于利用脉冲发生电路（例如，非稳定的多谐振荡器型开关装置）减小电桥式电导率传感器的设定点的漂移，以向导电单元电极提供非常短的持续时间的AC电压，以最小化累积极化 其中。 还提供脉冲延长电路以确保来自桥接电路的相对短的输出脉冲具有足够的持续时间以适当地操作用于将添加剂产品注入到导电介质中的装置。