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由加拿大魁北克水电研究院研制的,采用测量焊条阻抗防止电击的新装置,其基本部分是一个快速电子开关和阻抗探测回路。能切断电源与焊条间的回路,使焊工与电源隔绝,不需手动操作。也可用于潮湿环境中工作(如矿井、地下管道、贮液器等)。该装置与开关连接的测量回路用于确定电焊条与工件间的电动阻抗。只要阻抗超过测量临界值(焊条与人体接触),开关就保持开路状态(焊条上无电压)。相反,阻抗降到测量临界值以下,则开关闭合。因此,
Developed by the Quebec Institute of Hydroelectricity in Canada, a new device that measures the resistance of an electrode to prevent electric shock consists essentially of a fast electronic switch and impedance detection circuit. Can cut off the circuit between the power and the electrode, so that the welder and the power cut off, without manual operation. Can also be used in humid environments (such as mines, underground pipelines, reservoirs, etc.). The measuring circuit connected to the switch is used to determine the electrical impedance between the welding electrode and the workpiece. As long as the impedance exceeds the measured threshold (the electrode contacts the human body), the switch remains open (no voltage on the electrode). Conversely, the impedance drops below the measurement threshold, the switch closes. therefore,