PLC INPUT UNIT

摘要

The PLC input unit minimizes the number of terminals of photocoupler output section by using a matrix method. The photocouplers (PC11-PCmm) are arranged in the matrix form. The input unit (100) input terminal is connected to the cathode of a diode in each row of photocoupler. Each logic unit (30) terminal (T1-Tn) is connected to the emitter of transistor in each column of photocoupler. The coltage (Vcc) is applied to the anode of transistor through a resistor (R). The collector of transistor is connected to a terminal (+5V) and each output unit (200) terminal (O1-On). The PLC input unit has (m x n) input terminals and (m + n) output terminals.