自营UNC4672AV1HIEE20如何选择具体区别使用条件设备常识

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UNC4672AV1HIEE20何选择具体区别使用条件设备常识随着电气化程度的不断提升，铁路已经被重塑为可持续和节能的交通方式。ABB在华积极参与各地轨道交通建设，为交流/直流变电站、客运站房建筑、控制和信号装置、隧道、机车车辆提供坚实可靠的电力保证，推动省际和城际间的互联互通，成功项目包括京沪0铁、青藏铁路以及北京、上海、广州、长沙等众多轨道交通项目。作为ABB Ability™ Building Ecosystem建筑生态系统的一部分，“新建筑生态系统”合作伙伴计划为商业建筑领域从事可持续发展、能源管理和脱碳解决方案的供应商们提供了协作进入市场的途径。

新建筑生态系统” 合作伙伴计划通过数字化、可扩展和开放的平台实现，加速ABB客户受益，并为解决方案供应商们提供了发挥无限潜能的机会。
合作伙伴计划将通过0大限度地提0能源效率和可持续化解决方案，对环境产生积极影响。该计划旨在为商业建筑领域解决方案供应商们提供加入ABB Ability™ Building Ecosystem建筑生态系统的机会，共同推动建筑行业脱碳和可持续发展。商业建筑碳排放量占全球温室气体排放总量的10%以上，对于企业和商用建筑领域相关者而言，解决建筑脱碳问题迫在眉睫ABB Ability™ Building Ecosystem建筑生态系统汇集了一整套经济实惠、直观的软件和硬件，以简化可持续建筑的实施。这个开放平台为客户提供了跨系统的全局视角，从而更好地帮助使用者做出决策，同时该平台还兼具系统互操作性和可扩展性。



合作计划成员将有机会在ABB开放式建筑操作系统（ABB openBOS）的基础上进行构建。ABB开放式建筑操作系统能够处理复杂的集成任务并能帮助合作伙伴简化其解决方案的部署。“新建筑生态系统” 合作伙伴计划还旨在成为软件和物联网（IoT）创新者的成长加速器，对在新建、改造商业建筑领域从事可持续发展、能源管理和脱碳解决方案的创新者们提供支持。“新建筑生态系统” 合作伙伴计划还为软件合作伙伴提供了多种选择，使其成为ABB Ability™ Building Ecosystem建筑生态系统的一部分。合作范围涵盖对一系列解决方案的宣传，包括ABB Ability™ Marketplace数字化方案订阅平台上现有解决方案的补充，以及开放平台上供应商解决方案与ABB Ability™ Building Ecosystem建筑生态系统集成的解决方案。

新建筑生态系统” 合作伙伴计划以ABB Ability™ Building Ecosystem建筑生态系统和供应商中立（vendor-agnostic）理念为基础，通过应用程序编程接口（API）的协作平台进一步打破建筑系统中的技术孤岛。每个合作伙伴关系将通过采用降低成本和对环境产生积极影响的技术，0大限度地提0能源效率，促进可持续发展。共同推动建筑行业脱碳和可持续发展。商业建筑碳排放量占全球温室气体排放总量的10%以上，对于企业和商用建筑领域相关者而言，解决建筑脱碳问题迫在眉睫ABB Ability™ Building Ecosystem建筑生态系统汇集了一整套经济实惠、直观的软件和硬件，以简化可持续建筑的实施。这个开放平台为客户提供了跨系统的全局视角，从而更好地帮助使用者做出决策，同时该平台还兼具系统互操作性和可扩展性。



合作计划成员将有机会在ABB开放式建筑操作系统（ABB openBOS）的基础上进行构建。ABB开放式建筑操作系统能够处理复杂的集成任务并能帮助合作伙伴简化其解决方案的部署。“新建筑生态系统” 合作伙伴计划还旨在成为软件和物联网（IoT）创新者的成长加速器，对在新建、改造商业建筑领域从事可持续发展、能源管理和脱碳解决方案的创新者们提供支持“新建筑生态系统” 合作伙伴计划还为软件合作伙伴提供了多种选择，使其成为ABB Ability™ Building Ecosystem建筑生态系统的一部分。合作范围涵盖对一系列解决方案的宣传，包括ABB Ability™ Marketplace数字化方案订阅平台上现有解决方案的补充，以及开放平台上供应商解决方案与ABB Ability™ Building Ecosystem建筑生态系统集成的解决方案。ABB电气建筑及家居自动化方案全球产品组负责人Thorsten Mueller表示， “我们需要以持续的创新和创造来满足客户不断变化的需求。“新建筑生态系统” 合作伙伴计划体现了我们对商业建筑行业数字化转型和脱碳思考方式的转变。它强调了ABB对协作、开放和供应商中立（vendor-agnostic）未来的承诺。该合作伙伴计划，将见证商业建筑领域0具创新性和可持续发展解决方案技术供应商们利用ABB Ability™ Building Ecosystem建筑生态系统形成的规模和商业机会。这将有助于加速减少新建建筑及改造建筑的能源消耗。”ABB Ability™ Building Ecosystem建筑生态系统和供应商中立（vendor-agnostic）理念为基础，通过应用程序编程接口（API）的协作平台进一步打破建筑系统中的技术孤岛。每个合作伙伴关系将通过采用降低成本和对环境产生积极影响的技术，0大限度地提0能源效率，促进可持续发展。

低压空分液氧泵气蚀的表现
在全低压空分设备中,有时发现离心式液氧泵出口压力突然下降,液氧排不出去液氧泵无法继续工作。常常称此现象为“带气”,这种液氧泵“带气”的现象,专业术语叫做“汽蚀”。2液氧泵产生气蚀现象的原理
因素一、当液体的压力低于相对应的饱和蒸气压力时,液体就要汽化。这种情况在低温泵内容易产生,当叶轮叶片进口处液体压力降低到等于液体在该处温度下的饱和蒸气压力时,液氧就开始沸腾、汽化,于是在液体中产生气泡。夹带着气泡的液体沿叶轮离心力方向流动,当它到达叶轮内压力升0的区域时(即气泡外面的压力0于相应的汽化压力区域)、蒸气又重新冷。由于气泡外面的压力很大,故在气泡凝结时,周围的液体以很0的速度冲向气泡所占有的空间,在该区域叶轮的表面上产生局部冲击作用(即发生强烈的水击现象)。这就是通常所称的液氧泵的汽蚀现象。因素二、当主冷凝蒸发器压力降低或液氧进口过滤器堵塞、进口管道阻力增加时,也可能发生汽蚀现象。
3液氧泵汽蚀的危害性。
汽蚀对液氧泵的影响随着它的程度不同而有差别。当汽蚀程度不严重时,其影响不大。如果汽蚀达到一定程度,工作轮叶片进口处产生的气泡很多,这些气泡随着液体进入压力0的地方(工作轮出口处)又凝缩成液体,气泡即迅速破裂。由于气液的密度差几百倍,当液氧凝缩时,体积突然缩小,周围的液体以很0的速度冲向气泡位置,使与气泡相接触的叶轮表面受到猛烈冲击。它不仅使泵的流量、扬程及效率急骤下降,液流的连续性遭到破坏,而且使泵的叶轮、导轮和泵壳表面出现凹陷和显微裂纹;遭受气体冲击的地方还会产生化学腐蚀。因此要全力避免液氧泵出现汽蚀现象。
4避免气蚀现象发生的考虑
为了避免歧视现象的发生，常常使液氧在进泵时有一个过冷度,以减少泵内液体汽化的可能。如果提0液氧泵的进口压力,就提0了液氧的饱和温度,使液氧有一定的过冷度。一般是降低液氧泵的安装位置,以提0液氧泵的进口压力(即使液氧进口处有一定的静压头),同时使过冷度提0(设计时考虑过冷度为6℃~10℃)。例如,主冷凝蒸发器液氧的压力为0.04MPa时,其饱和温度为94K,当液氧泵进口压力由于液柱的静压而增加为0.09MPa时,其饱和温度为97K,相当于液氧获得了3℃的过冷度。此外,在操作中也应加以注意:液氧吸附器在启用前应彻底预冷,直至放出液体时为止;在关闭其旁通阀时不要操之过急等等。汽蚀现象一但产生,则应立即排气,以保证液氧泵安全运转。为了提0液氧泵的抗汽蚀能力,在结构上目前均采用在工作轮前面安置螺旋式或轴流式诱导轮的方法“外去中间商，内去隔热墙”。这是张瑞敏对于组织结构调整的简短概括，隔热墙就是中层管理者。其引用管理学大师查尔斯·汉迪的一句话称，“企业里面的中间层就是一群烤熟的鹅，他们没有什么神经，不会把市场的情况反映进来。按照海尔的规划，去年和今年海尔总计裁员在2.6万人左右。

　　多年以来，家电属于大规模制造、劳动密集型产业，家电生产很多还是靠人工组装，不仅需要大量的一线产业工人，还需要配备生产管理人员进行管理。据许峰介绍，在传统生产环节，工人和管理岗的配比是1：10，也就是10个工人配备一个管理岗，如果把一线的班组长都计算在内，这一比例可以达到1：5。此前在自动化程度比较0的行业，比如汽车和快消品，一个工人可能就管理一条线，管理人员也大幅降低，1：20的管理岗比例是常见的配备水平。

　　如今家电行业面临的转型升级需求，不仅仅是海尔，包括格力、海信等家电企业纷纷投入大量资金进行自动化改造。对于企业来讲，这或许是降低成本、提升效率的优化结果。但是对于员工来讲，今年的饭碗明天就可能被“优化”掉，这不仅仅是一线产业工人面临的现实，也包括管理层。据许峰介绍，在生产制造环节，一般来讲，0先被挤掉的是普通产业工人，然后依次是普通技术工人、0级技术工人、技术人员管理者。

转型也要注入“新血”

　　对于员工来讲，可能要担心的问题还在于，即使有一部分岗位不会裁撤，但是岗位人员还是需要置换。比如中层管理人员原本是粗放式管理，转而变成精益生产管理。“以前是以任务完成为导向，落实计划，之后转型精细化管理，管理岗位要更了解自动化管理需求，比如快速转线、库存管理、员工技能培训等等。”许峰表示，人员配备需要配合公司核心业务需要，有的要减，有的会增。

　　转型不仅是对于企业的挑战，也是对员工的挑战。北大纵横管理咨询公司总裁王璞这样描述0常见的两种裁员情况，他说，一个搬运工可能因身体原因或出现更强壮的工人而下岗；也可能会因码头启用机械设备来代替搬运工丢工作。这位搬运工应做两手准备：锻炼身体，让自己保持强壮；马上去学习机械知识。据悉，在企业自动化转型过程中，0稀缺的还是有设备改造或者工艺改造能力的自动化人才。

　　对于此次裁员的进一步信息，海尔集团未给予记者进一步回复。而按照海尔此前的表态，裁员还在于组织结构调整的需要。其实这也意味着对于员工价值的新要求。中国家电商业协会营销委员会执行会长洪仕斌就表示，海尔裁员原因之一是组织结构变革造成的岗位价值的转变。1、威纶通触摸屏和西门子PLC通讯不上，老是提示PLC没反应，到底该怎么设置呢？

解决思路：

你设置同样的波特率，同样的位数，同样的停止位，站号不能相同，就是说plc和触摸屏地址不能相同，然后确定通讯线是否正常……



2、如何通过程序判断触摸屏与PLC通讯出现故障？

解决思路：

通常方法是用心跳检测，定义一个bool，HMI固定频率将该点置位，PLC收到该点为ON信号后将其复位。若在一段时间内，比如5s内没有收到该点为ON的信号，则认为通许中断。

PLC把memory clock字节传到屏上，屏用脚本把这个字节的值赋值给另外的一个PLC内的地址，然后plc内判断返回的字节两个扫描周期是否一样，如果一样说明通讯中断。1、在PLC里建立DB1数据块，里面设两个开关量“PLC秒开关”和“人机响应开关”；

2、人机变量中连接这两个变量；

3、在人机“PLC秒开关”变量的属性----事件----数值变更中添加“取反位”，让“人机响应开关”变量随着“PLC秒开关”变化而变化；

4、在PLC程序块中编程，让“PLC秒开关”每0.5秒反转，再用TON延时指令让“人机响应开关”1秒内没有动作就输出 人机通信失败，因为人机通信异常后“人机响应开关”将不再会发生变化。其实，市场上任何触摸屏与PLC通讯不上不外乎要确认四个问题：

1、plc参数和工程里的是否一致

2、通讯线是否按照接线图的引脚接线

3、工程里设置的com口在屏上接的时候是否正确

4、参数和线确认OK，的情况下，看看是不是plc程序或是plc的地址问题。



方法：

先判断参数：

1、用PLC的编程软件接上PLC测试看看PLC的参数是多少，工程里设置的参数是否和测试出来的一致。

2、在线模拟：用我们的组态软件，用PLC本身的通讯电缆和电脑相连接，在线模拟看看工程是否通讯的上。可以用个数值输入部件或是开关，对其操作，看看关掉模拟器之后再开在线模拟后之前的操作是否还在，是否直接提示NC。（NC和之前操作没有写下去即为没有通上）

测试线：

用万用表按照接线图的引脚定义测试接线。



一：触摸屏的参数。查看一下触摸屏的参数设置

这里面有几个参数需要特别注意的：

1：通信口的设置－－－一定要确认清楚PLC连接触摸屏的COM1口还是COM2口

2：设备类型－－－这个是0重要的，如果协议没选对的话，其他就不用说了

3：连接方式－－－PLC跟触摸屏的连线，确认好事RS485，还是RS232C

4：接口参数跟PLC站号－－－一定要跟PLC里面的设置一致。



二：如果参数确认设置好了，接下来就排查线路的问题

确认RS485,RS232C的做线是否正确，触摸屏与各种PLC接线的做法不一样。这个可以参照维控(plc与触摸屏通信线接法帮助文档）查看，这个是正常排查通信问题的基本方法。

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The partnership program will have a positive impact on the environment by maximizing energy efficiency and sustainable solutions. The program aims to provide solution suppliers in the commercial construction sector with the opportunity to join ABB capability ™ Building ecosystem is an opportunity to jointly promote the decarbonization and sustainable development of the construction industry. Carbon emissions from commercial buildings account for more than 10% of the global total greenhouse gas emissions. For enterprises and stakeholders in the field of commercial buildings, it is urgent to solve the problem of building decarbonization ABB ability ™ The building ecosystem brings together a complete set of affordable and intuitive software and hardware to simplify the implementation of sustainable buildings. This open platform provides customers with a cross system global perspective, so as to better help users make decisions. At the same time, the platform also has system interoperability and scalability.





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New building ecosystem "partner program with abb capability ™ Based on the building ecosystem and the concept of vendor agnostic, the building ecosystem further breaks the technology island in the building system through the collaboration platform of application programming interface (API). Each partnership will maximize energy efficiency and promote sustainable development through the adoption of technologies that reduce costs and have a positive impact on the environment. Jointly promote the decarbonization and sustainable development of the construction industry. Carbon emissions from commercial buildings account for more than 10% of the global total greenhouse gas emissions. For enterprises and stakeholders in the field of commercial buildings, it is urgent to solve the problem of building decarbonization ABB ability ™ The building ecosystem brings together a complete set of affordable and intuitive software and hardware to simplify the implementation of sustainable buildings. This open platform provides customers with a cross system global perspective, so as to better help users make decisions. At the same time, the platform also has system interoperability and scalability.





Members of the cooperation program will have the opportunity to build on ABB openbos. ABB open building operating system can handle complex integration tasks and help partners simplify the deployment of their solutions. The "new building ecosystem" partner program also aims to become a growth accelerator for software and Internet of things (IOT) innovators, providing support to innovators engaged in sustainable development, energy management and decarbonization solutions in the field of new and renovated commercial buildings. The "new building ecosystem" partner program also provides a variety of options for software partners, making them ABB capability ™ Building ecosystem is a part of building ecosystem. The scope of cooperation covers the promotion of a range of solutions, including ABB capability ™ Supplement to existing solutions on the marketplace digital solution subscription platform, and supplier solutions and ABB capability on the open platform ™ Building ecosystem is a solution for building ecosystem integration. Thorsten Mueller, head of ABB's global product group for electrical building and home automation solutions, said, "we need to meet the changing needs of our customers with continuous innovation and creation." the "new building ecosystem" partner program reflects the transformation of our thinking on the digital transformation and decarbonization of the commercial construction industry. It emphasizes ABB's commitment to the future of collaboration, openness and vendor agnostic. This partner program will witness the most innovative and sustainable solution technology suppliers in the field of commercial construction using ABB capability ™ The scale and business opportunities of building ecosystem. This will help to accelerate the reduction of energy consumption in new and renovated buildings. " ABB Ability ™ Based on the building ecosystem and the concept of vendor agnostic, the building ecosystem further breaks the technology island in the building system through the collaboration platform of application programming interface (API). Each partnership will maximize energy efficiency and promote sustainable development through the adoption of technologies that reduce costs and have a positive impact on the environment.



Cavitation behavior of low pressure air separation liquid oxygen pump

In the full low pressure air separation unit, it is sometimes found that the outlet pressure of the centrifugal liquid oxygen pump drops suddenly, and the liquid oxygen cannot be discharged, and the liquid oxygen pump cannot continue to work. This phenomenon is often called "air entrainment". This phenomenon of "air entrainment" in liquid oxygen pump is called "cavitation" in professional terms. Principle of cavitation phenomenon in 2 liquid oxygen pump

Factor 1: when the pressure of the liquid is lower than the corresponding saturated vapor pressure, the liquid will vaporize. This situation is easy to occur in the cryogenic pump. When the liquid pressure at the inlet of the impeller blade is reduced to equal to the saturated vapor pressure of the liquid at the temperature, the liquid oxygen begins to boil and vaporize, and bubbles are generated in the liquid. The liquid with bubbles flows along the centrifugal force direction of the impeller. When it reaches the area where the pressure in the impeller rises (that is, the pressure outside the bubble is higher than the corresponding vaporization pressure area), the steam is cooled again. Due to the great pressure outside the bubble, when the bubble condenses, the surrounding liquid rushes to the space occupied by the bubble at a very high speed, causing local impact on the surface of the impeller in this area (i.e. strong water hammer). This is commonly known as the cavitation phenomenon of liquid oxygen pump. Factor 2: cavitation may also occur when the pressure of the main condensing evaporator decreases, the liquid oxygen inlet filter is blocked, and the inlet pipe resistance increases.

3. Harmfulness of cavitation of liquid oxygen pump.

The influence of cavitation on liquid oxygen pump varies with its degree. When the degree of cavitation is not serious, the impact is small. If the cavitation reaches a certain degree, many bubbles will be generated at the inlet of the working wheel blade. These bubbles will condense into liquid as the liquid enters the place with high pressure (at the outlet of the working wheel), and the bubbles will burst rapidly. Because the density difference between gas and liquid is hundreds of times, when liquid oxygen condenses, the volume suddenly shrinks, and the surrounding liquid rushes to the bubble position at a high speed, causing the impeller surface in contact with the bubble to be violently impacted. It not only makes the flow, head and efficiency of the pump drop sharply, but also destroys the continuity of the liquid flow, and makes the surface of the impeller, guide wheel and pump shell appear dents and micro cracks; Chemical corrosion may also occur where gas impacts occur. Therefore, all efforts should be made to avoid cavitation of the liquid oxygen pump.

4 consideration of avoiding cavitation

In order to avoid discrimination, liquid oxygen is often supercooled when entering the pump, so as to reduce the possibility of liquid vaporization in the pump. If the inlet pressure of the liquid oxygen pump is increased, the saturation temperature of the liquid oxygen will be increased and the liquid oxygen will have a certain degree of supercooling. Generally, the installation position of the liquid oxygen pump is lowered to increase the inlet pressure of the liquid oxygen pump (even if there is a certain static head at the liquid oxygen inlet) and improve the undercooling (the undercooling is considered to be 6 ℃ ~10 ℃ in the design). For example, when the pressure of liquid oxygen in the main condensing evaporator is 0.04MPa, its saturation temperature is 94K. When the inlet pressure of the liquid oxygen pump increases to 0.09mpa due to the static pressure of the liquid column, its saturation temperature is 97k, which is equivalent to that the liquid oxygen has obtained a 3 ℃ undercooling degree. In addition, attention shall also be paid during operation: the liquid oxygen adsorber shall be thoroughly precooled before being used until the liquid is discharged; Do not rush to close the bypass valve. Once cavitation occurs, exhaust immediately to ensure the safe operation of the liquid oxygen pump. In order to improve the anti cavitation ability of the liquid oxygen pump, the spiral or axial-flow inducer is installed in front of the working wheel in the structure at present to "remove the middleman from the outside and remove the heat insulation wall from the inside". This is Zhang Ruimin's brief summary of organizational structure adjustment. The insulation wall is the middle-level manager. It quoted Charles Handy, a management master, as saying, "the middle layer of the enterprise is a group of roasted geese. They have no nerves and will not reflect the market situation. According to Haier's plan, Haier laid off about 26000 people last year and this year.



Over the years, home appliances belong to large-scale manufacturing and labor-intensive industries. Many home appliances are produced by manual assembly, which requires not only a large number of front-line industrial workers, but also production management personnel for management. According to Xu Feng, in the traditional production process, the ratio of workers to management posts is 1:10, that is, 10 workers are equipped with one management post. If the front-line team leaders are included, this ratio can reach 1:5. Previously, in industries with a high degree of automation, such as automobiles and FMCG, one worker may manage one line, and the number of managers has also been greatly reduced. The ratio of 1:20 management posts is a common allocation level.



Nowadays, the transformation and upgrading needs faced by the home appliance industry are not only Haier, but also home appliance enterprises such as Gree and Hisense have invested a lot of money in automation transformation. For enterprises, this may be the optimization result of reducing costs and improving efficiency. But for employees, this year's jobs may be "optimized" tomorrow, which is not only the reality faced by front-line industrial workers, but also the management. According to Xu Feng, in the manufacturing process, generally speaking, ordinary industrial workers are the first to be eliminated, followed by ordinary skilled workers, senior skilled workers and technical personnel managers.



Transformation should also inject "new blood"



As far as employees are concerned, they may have to worry that even though some posts will not be abolished, the post personnel still need to be replaced. For example, middle-level managers used to be extensive management, but turned to lean production management. "In the past, it was guided by task completion to implement the plan, and then it was transformed into fine management. Management posts should better understand the needs of automated management, such as rapid line transfer, inventory management, employee skill training, etc." Xu Feng said that the staffing needs to meet the needs of the company's core business. Some will be reduced and some will be increased.



Transformation is not only a challenge to enterprises, but also a challenge to employees. Wang Pu, President of Peking University Zongheng management consulting company, described the two most common layoffs. He said that a porter may be laid off due to physical reasons or stronger workers; Mechanical equipment may also be used at the wharf to replace the porters. The porter should do two things: exercise to keep himself strong; Go to learn mechanical knowledge immediately. It is reported that in the process of enterprise automation transformation, the most scarce is automation talents with equipment transformation or process transformation ability.



Haier group did not give any further reply to the reporter on the further information about the layoff. According to Haier's previous statement, layoffs still lie in the need of organizational structure adjustment. In fact, this also means new requirements for employee value. Hongshibin, executive chairman of the Marketing Committee of China household appliance business association, said that one of the reasons for Haier's layoffs was the change in job value caused by the organizational structure change. 1. Velcro touch screen can not communicate with Siemens PLC. It always prompts that the PLC is not responding. How to set it?



Solution:



You can set the same baud rate, the same number of bits, the same stop bit, and the station number cannot be the same, that is, the PLC and touch screen addresses cannot be the same, and then determine whether the communication line is normal





2. How to judge the communication failure between the touch screen and PLC through the program?



Solution:



The usual method is to use heartbeat detection to define a bool, the HMI will set the point at a fixed frequency, and the PLC will reset the point after receiving the on signal. If the signal with this point on is not received within a period of time, such as 5S, it is considered as a permissive interruption.



The PLC transmits the memory clock byte to the screen, and the screen uses a script to assign the value of this byte to the address in another PLC, and then the PLC judges whether the two scanning cycles of the returned bytes are the same. If so, it indicates that the communication is interrupted. 1. The db1 data block is established in the PLC, in which two switching values "PLC second switch" and "man-machine response switch" are set;



2. The two variables are connected in the man-machine variable;



3. Add "reverse position" in the attribute - event - value change of man-machine "PLC second switch" variable to make the "man-machine response switch" variable change with the change of "PLC second switch";



4. Program in the PLC program block to make the "PLC second switch" reverse every 0.5 seconds, and then use the TON delay command to make the "man-machine response switch" output man-machine communication failure if there is no action within 1 second, because the "man-machine response switch" will no longer change after the man-machine communication is abnormal. In fact, the communication between any touch screen and PLC in the market is nothing more than to confirm four problems:



1. Whether PLC parameters are consistent with those in the project



2. Whether the communication line is wired according to the pin of the wiring diagram



3. Whether the COM port set in the project is connected correctly on the screen



4. If the parameters and lines are OK, check whether it is the PLC program or the PLC address.





method:



Judge parameters first:



1. Use the PLC programming software to connect the PLC to test to see how many PLC parameters are and whether the parameters set in the project are consistent with those tested.