英语翻译When defining the rules,refer back to the list of field devices developed.Start with the output instructions and work backward to define the condition that produces the desired action.It is important to remember that emergency-stop switch

英语翻译When defining the rules,refer back to the list of field devices developed.Start with the output instructions and work backward to define the condition that produces the desired action.It is important to remember that emergency-stop switch
英语翻译
When defining the rules,refer back to the list of field devices developed.Start with the output instructions and work backward to define the condition that produces the desired action.It is important to remember that emergency-stop switches should not be programmed in the programmable controller.Only a hardwired master control relay provides a reliable means for emergency shutdown.These emergency devices should therefore be documented as such.When writing,the text needs to use language that helps convert the operating characteristics to ladder logic.For instance,the AND logic function connects condition instructions in series on a ladder diagram rung,while the OR logic function connects inputs in parallel.
Addressing all elements of a ladder diagram involves identifying and labeling inputs and outputs with a letter/numerical designation.Use an “I” to indicate inputs and an “O” for outputs.(Designating O for zero will prevent confusion between O for output and the number zero).For instance,the first input device is addressed I/O,the second is I/1 and so forth.Outputs are addressed in the same fashion; O/O,O/1,O/2.The program is then downloaded into the programmable controller and ready to be tested.
Installing the Programmable Controller
Before installing the programmable controller,it is necessary to analyze the control cabinet currently housing the relays.Are all the field devices wired to terminal blocks?Or,are all the field devices brought into individual relays scattered throughout the panel?In essence,the engineer will have to mock-up a layout of the cabinet’s contents because the programmable controller typically takes up less space.This is important because if you pull relays out and install a small programmable controller in the middle of the panel,you will find that some of the wires may not reach.If this is the case,you may need to wire in terminal blocks to land the wires coming from the field and then wire from the terminal blocks to the programmable controller.This process is obviously easier when the relays are wired to terminal blocks because you do not have to disturb the field side of the terminal strip wiring -- all you have to do is modify the control side that connects to the programmable controller.At this point the field wires should be labeled with the device names,I/O address or some other identifying code to help document the installation and simplify troubleshooting.Color coding similar characteristics such as AC vs.DC devices further simplifies this process.

英语翻译When defining the rules,refer back to the list of field devices developed.Start with the output instructions and work backward to define the condition that produces the desired action.It is important to remember that emergency-stop switch
当定义规则,参考前面的现场设备的名单中发展.开始与输出指令和工作落后的情况下定义生产预期的行动.重要的是要记住,emergency-stop开关不应该安排上,可编程控制器.只有硬布线主人控制继电器提供了可靠的手段,紧急停车.这些紧急设备,因此应该被记录.在书写时,文本需要使用语言,帮助转换操作特点,梯子的逻辑.例如,逻辑函数的连接状态指示的比分的梯形图响,而或逻辑函数连接输入相似.
解决所有的元素的梯形图包括识别输入和输出和标注字母/数值的称号.用“我”来表示输入和一个“O”为输出.(指定O为零将防止混淆O输出和数字0).例如,第一个输入设备是寄I / O,其次是我/ 1等等.同样需要解决的输出时尚;O /啊,阿O / 1 / 2.这个计划是然后下载到的可编程控制器,并准备测试.
安装可编程控制器
在安装之前,可编程序控制器,我们有必要分析一下控制箱目前房屋继电器.都是现场装置连接到终端的吗?或者,所有的现场设备带进个人继电器分散在面板?在本质上,工程师必须布局模型在内阁成员内容因为可编程序控制器通常占用较少的空间.这是很重要的,因为如果你拉继电器,安装一个小可编程控制器在中间的面板,你会发现有些的导线都无法到达.在这种情况下,你可能需要丝,在接线端子登陆电线来自田野,然后线从终端的街区,到可编程控制器.这个过程是很明显变得更轻松的、连接到终端继电器是进一步简化了这个过程.