1756-A17/B 可编程控制处理器  PLC控制器

1756-A17/B 可编程控制处理器  PLC控制器

详细介绍

PLC及各单元布置与CPU单元相邻的单元，是特殊单元和输入单元等干扰产生少的单元。外部电路的电磁接触器及电器类，其线圈及接点即干扰发生源，因此应与PLC分开配置。（大致在100mm以上）此外模块是PLC系统的主要部件，需经常进行调试维护，应安装在方便操作的位置。安装模块时自左向右排布，便于扩展。

信号线较多，通常选用80mm宽的线槽，机架上端与线槽的净距在30mm左右，机架下端与线槽的净距在80mm左右。PLC和变频器屏蔽线的接法原则为防止plc和变频器之间的控制信号线受空间电磁场的干扰，可在这些控制信号线的外层接屏蔽线，以提高系统的抗干扰能力。此种接线一定要注意，对屏蔽的接地点只能选取一点。不管是在PLC一边，还是在变频器的一边。一般选在信号接收端，即变频器一边。

这样，可提高系统的抗干扰能力。如果屏蔽线在两端都接地，会使屏蔽线上有电流流过，不但不能提高系统的抗干扰的能力，反而会加重外界对PLC的干扰。PLC柜型的选择适用于装PLC的柜型，通常选用固定柜，且门板为整门的柜型，如KB柜、九折柜和十六折柜等，不宜选GGD柜、固定分割柜、抽屉柜。因为PLC柜内元件基本上为整板安装，如果采用了柜门分割的柜型，不便于安装和调试。对于GGD柜如果必须选用时，需做一下非标设计，将仪表门、前门和下通风门合并成一个整门，且柜体框架上取消前后横梁，以便于安装和维护。

1756-A17/B 可编程控制处理器  PLC控制器

Detailed introduction

The PLC and the units arranged adjacent to the CPU unit are units with less interference such as special units and input units. Electromagnetic contactors and electrical appliances of the external circuit, whose coils and contacts are the sources of interference, should be configured separately from the PLC. (roughly more than 100mm) In addition, the module is the main part of the PLC system, which needs to be regularly debugging and maintenance, and should be installed in a convenient location. When installing modules, they are arranged from left to right for easy expansion.

Generally, 80mm wide cable slots are used. The clear distance between the upper end of the rack and the cable slots is about 30mm, and the clear distance between the lower end of the rack and the cable slots is about 80mm. In order to prevent the control signal line between the plc and the frequency converter from being interfered with by the space electromagnetic field, the shielding line can be connected to the outer layer of these control signal lines to improve the anti-interference ability of the system. This connection must be noted that only one point can be selected for the shielded ground point. Whether it is on the PLC side or on the inverter side. Generally selected at the signal receiving end, that is, the frequency converter side.

In this way, the anti-interference ability of the system can be improved. If the shielding line is grounded at both ends, the shielding line will have current flow, not only can not improve the anti-interference ability of the system, but will increase the interference of the outside world to the PLC. The selection of PLC cabinet type is suitable for the cabinet type of PLC, usually the fixed cabinet is selected, and the door panel is the cabinet type of the whole door, such as KB cabinet, 10% cabinet and 16% cabinet, etc., it is not appropriate to choose GGD cabinet, fixed partition cabinet, drawer cabinet. Because the components in the PLC cabinet are basically installed as a whole board, if the cabinet type with the cabinet door divided is used, it is not easy to install and debug. For the GGD cabinet, if it must be selected, it is necessary to do a non-standard design, the instrument door, the front door and the lower ventilation door are merged into a whole door, and the front and rear beams are eliminated on the cabinet frame, so as to facilitate installation and maintenance.