PM856AK01 3BSE066490R1 ABB

PLC generally accepts the input switch signal such as travel switch,limit switch and so on.Input terminal is the port of PLC and external sensor load conversion signal.Input wiring generally refers to the wiring between external sensors and input ports.

The input device can be any passive contact or open collector NPN tube.When the input device is connected,the input terminal is connected,the input circuit is closed,and the LED indicating the input is on at the same time.

The primary circuit and the secondary circuit at the input end are isolated by photoelectric coupling.The secondary circuit is equipped with an RC filter to prevent the PLC from malfunctioning due to the jittering of the input contacts or the electrical noise coming in from the input line.

If a diode is connected in series with the input contact circuit,the voltage across the series diode should be less than 4V.If using a reed switch with light-emitting diodes,the number of diodes in series cannot exceed two.

PLC一般接受行程开关、限位开关等输入的开关量信号。输入接线端子是PLC与外部传感器负载转换信号的端口。输入接线，一般指外部传感器与输入端口的接线。

输入器件可以是任何无源的触点或集电极开路的NPN管。输入器件接通时，输入端接通，输入线路闭合，同时输入指示的发光二极管亮。

输入端的一次电路与二次电路之间，采用光电耦合隔离。二次电路带RC滤波器，以防止由于输入触点抖动或从输入线路串入的电噪声引起PLC误动作。

若在输入触点电路串联二极管，在串联二极管上的电压应小于4V。若使用带发光二极管的舌簧开关，串联二极管的数目不能超过两只。