![](https://csdnimg.cn/release/download_crawler_static/87708946/bg5.jpg)
ABSTRACT
PLC application field has been broaden from various fields, in daily
life, intelligent vies to answer first device widely used in various
competitions and vies to answer first occasion. Due to the PLC system
responder relative stability, so imagine can use PLC for the design of
the responder.
Before start vies to answer first, the first through the reset button
realize circuit reset, the questions later, open the selector switch start
timer. In vies to answer first time, when a group of preemptive press vies
to answer first button, the corresponding auxiliary relay on, at the same
time cut off other vies to answer first circuit, realize interlock. Vies
to answer first after the success of the auxiliary relay on, start sound
circuit and some points table lamp, drive external digital display shows
vies to answer first successful group number. After the success of the
vies to answer first, and the launch of the timer, when the timer timing
over, start sound circuit and light hint time to answer. If the time no
contest, will enable audio circuit and desk lamp.
Key word: responder; PLC (programmable logic controller);