6DS1315-8AC SIEMENS 输入输出（I/O）模块

一般来说，PLC是极其可靠的设备，出故障率很低。PLC的CPU等硬件损坏或软件运行出错的概率几乎为零；PLC输入点如不是强电入侵所致，几乎也不会损坏；PLC输出继电器的常开点，若不是外围负载短路或设计不合理，负载电流超出额定范围，触点的寿命也很长。因此，我们查找电气故障点，重点要放在PLC的外围电气元件上，不要总是怀疑PLC硬件或程序有问题，这对快速维修好故障设备、快速恢复生产是十分重要的，因此笔者所谈的PLC控制回路的电气故障检修，重点不在PLC本身，而是PLC所控制回路中的外围电气元件。

输入输出（I/O）模块的选取
输出模块分为晶体管、双向可控硅、接点型。
晶体管型的开关速度快（一般0.2ms），但负载能力小，约0.2~0.3A、24VDC，适用于快速开关、信号联系的设备，一般与变频、直流装置等信号连接，应注意晶体管漏电流对负载的影响。

可控硅型优点是无触点、具有交流负载特性，负载能力不大。
继电器输出具有交直流负载特点，负载能力大。常规控制中一般首先选用继电器触点型输出，缺点是开关速度慢，一般在10ms左右，不适于高频开关应用。

In general, PLC is extremely reliable equipment, the failure rate is very low. The probability of hardware damage such as PLC CPU or software running error is almost zero; If the PLC input point is not caused by strong electricity intrusion, it will almost not be damaged; The normal open point of the PLC output relay, if not the peripheral load short circuit or unreasonable design, the load current exceeds the rated range, and the life of the contact is also very long. Therefore, we find the electrical fault point, focus on the PLC peripheral electrical components, do not always suspect PLC hardware or program problems, which is very important for rapid maintenance of faulty equipment, rapid resumption of production, so the author talked about the electrical fault repair of the PLC control loop, the focus is not on the PLC itself, It is the peripheral electrical components in the circuit controlled by the PLC.

Input/Output (I/O) module selection
The output module is divided into transistor, bidirectional thyristor and contact type.
The transistor type switching speed is the fastest (generally 0.2ms), but the load capacity is the smallest, about 0.2-0.3A, 24VDC, suitable for fast switching, signal contact equipment, generally connected with frequency conversion, DC devices and other signals, should pay attention to the influence of transistor leakage current on the load.

Thyristor type has the advantages of no contact, AC load characteristics, and little load capacity.
The relay output has the characteristics of AC and DC load, and the load capacity is large. In conventional control, the relay contact type output is generally selected first, and the disadvantage is that the switching speed is slow, generally about 10ms, which is not suitable for high-frequency switching applications.

其他型号推荐：