4351B模块备件使用速度

若 PLC 操控的体系需求联入工厂主动化网络，则 PLC 需求有通讯联网功用，即要求 PLC 应具有衔接其他 PLC 、上位核算机及 CRT 等的接口。大、中型机都有通讯功用，目前大部分小型机也具有通讯功用。
（ 7 ）对 PLC 结构办法的挑选
在相同功用和相同 I/O 点数据的状况下，全体式比模块式价格低。但模块式具有功用扩展灵活，维修便利（换模块），简略判断毛病等长处，要按实践需求挑选 PLC 的结构办法。

If the system controlled by PLC needs to be connected to the factory automation network, PLC needs to have the function of communication networking, that is, PLC should have the interface connecting other PLCs, upper accounting computers and CRTs. Both large and medium-sized computers have communication functions. At present, most small computers also have communication functions.
(7) Selection of PLC structure method
Under the condition of the same function and the same i/o point data, the price of all-in-one type is lower than that of modular type. However, the modular type has the advantages of flexible function expansion, convenient maintenance (changing modules), simple judgment of faults and so on. The structural method of PLC should be selected according to practical needs.