YPR201A YT204001-KE ABB

Input wiring

●Generally,the input wiring should not be too long.However,if the environmental interference is small and the voltage drop is not large,the input wiring can be appropriately longer.

●The input/output lines cannot use the same cable,and the input/output lines should be separated.

●As far as possible,use the form of normally open contact to connect to the input terminal,so that the compiled ladder diagram is consistent with the relay schematic diagram,which is easy to read.

output connection

●Output terminal wiring is divided into independent output and common output.In different groups,different types and voltage classes of output voltages can be used.But the outputs in the same group can only use the same type of power supply with the same voltage level.

●Since the output components of the PLC are packaged on the printed circuit board and connected to the terminal board,if the load connected to the output components is short-circuited,the printed circuit board will be burned.

●When using the relay output,the size of the inductive load it bears will affect the service life of the relay.Therefore,when using the inductive load,a reasonable choice should be made,or an isolation relay should be added.

●The output load of the PLC may cause interference,so measures should be taken to control it,such as the protection of the freewheeling tube of the DC output,the resistance-capacitance absorption circuit of the AC output,and the shunt resistance protection of the transistor and triac output.

输入接线

●输入接线一般不要太长。但如果环境干扰较小，电压降不大时，输入接线可适当长些。

●输入/输出线不能用同一根电缆，输入/输出线要分开。

●尽可能采用常开触点形式连接到输入端，使编制的梯形图与继电器原理图一致，便于阅读。

输出连接

●输出端接线分为独立输出和公共输出。在不同组中，可采用不同类型和电压等级的输出电压。但在同一组中的输出只能用同一类型、同一电压等级的电源。

●由于PLC的输出元件被封装在印制电路板上，并且连接至端子板，若将连接输出元件的负载短路，将烧毁印制电路板。

●采用继电器输出时，所承受的电感性负载的大小，会影响到继电器的使用寿命，因此，使用电感性负载时应合理选择，或加隔离继电器。

●PLC的输出负载可能产生干扰，因此要采取措施加以控制，如直流输出的续流管保护，交流输出的阻容吸收电路，晶体管及双向晶闸管输出的旁路电阻保护。