PLC's IO module input sampling stage works
plc analog io module image area corresponding the unit. After the end of the plc input module sample, into the user program execution and output refresh period. In both stages, and even if the input data changes state, status, and data g-input-output-module/">IO module plc of the image area of the corresponding cell is not changed. Therefore, if the input is a pulse signal, the width of the pulse signal must be greater than one scanning cycle, in order to ensure that in any case, the input can be read.