With a start button QA, a stop button TA D to achieve a motor start, stop control. Its AC contactor for KM. Draw terminal wiring diagram of the control system; lists the I / O allocation table; design ladder.
Analysis example
1) Terminal Blocks
2) I / O assignment Input Output
QA-X0 KM-Y0
TA-X1
0 when input contact input terminal (QA) is turned on, input relay X0 coil excited, its normally open contact closure X0, Y0 output relay coil is excited by its normally open contacts self-retaining. KM AC contactor is energized, the motor starts normally. When No. 1 input contact input terminal (TA) is turned on, enter the relay coil Xl stimulated, the normally closed contacts to open Y0 coil energized and open self-locking, the motor stops running.
In programming the PLC, start, reset circuit is the most basic common electrical control circuit, and a variety of programming methods.
PLC ONE 