论文部分内容阅读
本文介绍一种简单实用的抢答电路,它由按钮开关、继电器和彩色灯泡组成(见附图)。该电路由交流220V市电供电,可供四个小组使用。它具有电路元件少、故障率低、工作可靠等特点。 该抢答电路的工作原理如下:抢答开始后,如果第一小组抢先按下按钮开关SB1,则继电器KA1线图通电,其常开触点KA1-4闭合,指示灯H1亮。与此同时,其常闭触点KA1-1、KA1-2、KA1-3都断开,使继电器KA2、KA3、KA4回路断开。这时其它小组再按按钮开关SB2、SB3、SB4,相应的继电器KA2、KA3、KA4也不能吸合,指示灯H2、H3、H4均不亮,起到
This article describes a simple and practical answer circuit, which consists of button switches, relays and color light bulbs (see photo). The circuit is powered by an AC 220V mains and is available to four teams. It has less circuit components, low failure rate, reliable and so on. The operation principle of the response circuit is as follows: After the start of the response, if the first group presses the button switch SB1 first, the relay KA1 is energized. The normally open contact KA1-4 is closed and the indicator H1 is bright. At the same time, its normally closed contacts KA1-1, KA1-2, KA1-3 are off, so that the relay KA2, KA3, KA4 circuit off. At this time other groups press the button switch SB2, SB3, SB4, the corresponding relay KA2, KA3, KA4 also can not pull, the indicator H2, H3, H4 are not bright, play