I/O工程成功的八个考虑因素

The days when every device in an automated system had to be installed using multiple wires are over. While proper system design can still be challenging, technology advances in I/O have greatly reduced engineering and installation time and the wiring errors that once caused frustrating delays in the commissioning of new automated equipment.

Jeanne Schweder, Contributing Writer

2013年7月11日

1。运动需求确定性I/O。Try to have deterministic data transfer. If motion is I/O sensitive, then you need deterministic I/O to synchronize to the motion task, so that events happen in the same time interval.

2。Quick connections.在为您的控制柜选择终端块时，请寻找具有可以快速安装的预制跳线的终端块。这将节省以后的时间。

3。匹配规格。重要的是要了解有关您在开发项目规格时接口的所有组件的所有信息。如果其他人提供零件，请找出它们是NPN还是PNP，如果模拟信号是电压或电流，则任何握手要求以及干式接触数字或高级通信。这似乎很简单，但是与I/O不符的一个关键组件可能会引起大头痛。

4。Field electronics.Ensure that I/O electronic interfaces can be implemented directly in the field, allowing you to replace the junction box multi-conductor back to the equipment, rack or MCC room. Field electronics need to be G3 rated per ISA standard (S71.04).

5。Shorten commissioning.I/O分配在减少自动化项目的调试持续时间中起关键作用，然后在开始调试活动之前进行适当的循环测试。

6.延迟布局。The design team working on the project should not begin the planning and layout drawings for distributed I/O in the facility until all equipment OEMs have provided general arrangements. Provide the team with an overall scope on what these cabinets are called by name, and what area of the facility each will handle. Timing of this design phase with the up-front engineering will save time and money.

7.留出空间进行扩展。确保您的新控制柜有足够的空间，可容纳该机柜所需的所有点。还为未来的意外变化和升级所需的扩展余地提供了空间。对于I/O接线，请计划通过程序地址从设备的那一侧连接到I/O点的电路接线部分。这将减少您的技术人员以后对这些电路的问题进行故障排除所需的时间。电路标签的其余部分应基于打印线号。

8.Diagnostics.Make use of the built-in diagnostic information provided by most I/O systems. Good information for the operator can save you a lot of production time.

Remote I/O pitfalls.

有许多设计陷阱,以避免当重击oping I/O systems. The options now available to the designer are limited mostly by hardware price point, once you understand the purpose, location and lifecycle issues. Just because a thing can be done, however, does not mean that it should. Remote I/O options, for example, are growing, which can reduce wiring and terminal block needs in some cases by over 50-80 percent compared to what was available just 10 years ago. But serious thought has to be given to proper documentation and training of plant personnel to repair and maintain the system and prevent downtime. The documentation should include troubleshooting methodology in addition to part number, manufacturer, MAC address, etc. The control software should also be integrated with the remote I/O layout to allow for either remote troubleshooting or status information. If these simple things are not properly accounted for and implemented, the actual usage of the remote I/O may not be worth the savings.