PROGRAMMABLE CONTROLLER WITH INPUT/OUTPUT SIGNAL CONVERTING CIRCUIT FOR VARIABLY SETTING A NUMBER OF INPUTS AND/OR OUTPUTS

摘要

A programmable controller with an I/O signal converting circuit having an input element and an output element, comprises a signal I/O unit having a plurality of element sockets capable of replaceably accommodating both the input element and the output element; a selecting unit for selecting the type of the accommodated element; and a signal storing and sending unit. Each element socket may accommodate the input and output elements. Therefore, the space required to install the I/O circuits is reduced, and the number of input and output elements can be arbitrarily set.