上海宝山钢铁总厂钢管厂连轧机后的斯惠顿杠杆采用两台85kW绕线型感应电机传动,用PLC可编程序控制器控制。整套设备系从德国BBC公司引进。在实际运行中,因接触器动作频繁,故接触器的触头因工作电流大而经常烧损,影响生产正常运行。经设备部和钢管厂组成的攻关组的努力,现已研制出可控硅无触点开关,用来替换原来的交流接触器。新研制的可控硅无触点开关采用脉冲触发系统,从而减少了脉冲变压器的容量和可控硅元件的触发 Steel plant in Shanghai Baoshan Iron and Steel Plant Mill, followed by Swinton leverage two 85kW wound induction motor drive, PLC programmable logic controller. The whole set of equipment imported from Germany BBC company. In actual operation, due to the frequent contactor action, the contacts of the contactor frequently burn due to the large operating current, affecting the normal operation of the production. After the equipment department and the steel pipe factory composed of the efforts of the research group has developed a non-contact switch thyristor, used to replace the original AC contactor. The newly developed thyristor contactless switch using pulse trigger system, thereby reducing the capacity of the pulse transformer and SCR trigger