ron bocian最后一次访问制造商的设施，以调查涉及的安全事件UrschelSlicer，他发现有人误行了这台机器，以便它没有提供所需的保护水平。这肯定不是第一次发生的事情。
Bocian, the electrical engineer and risk manager at Urschel Laboratories, a Chesterton, Ind.-based OEM of food cutting technology, knows you can design a machine that is as safe as it can possibly be, but there will always be the fear of the unknown. It’s what Bocian calls reasonable foreseeable misuse. “What’s an operator going to do to get injured that you couldn’t foresee them doing?” he asks.
Urschel has been making slicers and dicers since the 1950s, so the company has an in-depth understanding of how operators will use the product and, therefore, how to safeguard it. But as end users ask for more machine flexibility to deal with changing consumer demands, and as Industry 4.0 initiatives connect more equipment, robots, and devices—thereby creating more moving parts on the manufacturing floor—there are new, unexpected safety risks.
“当有人重塑车轮时，你不知道要期待什么以及人们如何滥用产品，”博安说。
Making a machine safe is a priority for OEMs and manufacturers alike, as they want to protect employees and they need to comply with the safety regulations of the职业安全与健康管理局（OSHA）. But safety measures have not always been executed well because safety is not always easy.
“安全可以令人恐惧，因为该技术可以复杂且挑战，委托，操作和排除术语，”高级技术营销经理John Klesk表示安全Banner Engineering.
And technical troubles aren’t the only cause of safety snafus, of course. The people involved in the process often contribute as well.
“许多机器制造商和制造商正在努力解决精神障碍 - 所在的精神障碍是[假设的情况]应用于制造过程的安全性具有降低该过程的效率或生产力的结果，”TÜV认证功能乔治认证功能罗克韦尔自动化的安全专家和认证功能安全工程师。“这是我认为在制造业中根深蒂固的东西。我的制造经验是我的。[我以为]越安全[那是]放在某物的情况下，正在进行的停机时间越多，而且没有生产力。但我学会了作为一个系统设计师，绝对不真实。就像任何工具一样，它是你使用它的方式以及它集成到控制系统中的过程以及产生差异的过程。“
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Safety steps
一旦克服了我ntal hurdle, manufacturers must identify where to start implementing safety technology on machines. In an effort to demystify what can be a confusing endeavor, industry experts recommend starting with a risk assessment comprised of multiple steps: identifying hazards, assessing the risk, reducing risk to an acceptable level, documenting the results, and following up to ensure the machine does what it’s supposed to do.
“风险评估至关重要”，“Zachary Stank，产品营销经理，安全和光线凤凰联系美国。“You have to know what you are protecting in order to protect it.”
In addition, a risk assessment adds some order to the process. Without it, Stank says, “you are going in blind and you’ll miss something or you’ll overprotect the machine, spend way too much [on it], and price yourself out of the competition.”
这种风险缓解不仅仅是一种了解适用于机器的安全技术的运动，它也是解决申请和行业法规的方式。例如，如果要在食品行业使用机器，则需要考虑卫生要求。
“Unfortunately, food safety is contradictory to machine safety,” Urschel’s Bocian says. “Machine safety is about adding interlocks that are creating crevices for bacteria to harbor. They are two competing safety issues. It’s a balancing act.”
最重要的是，有许多安全标准和设备要求，甚至可以留下精明的机器制造商刮伤他们的头部。例如，作为制造工厂中使用的包装机的一部分集成的机器人必须遵循至少九个标准International Organization for Standardization (ISO),American National Standards Institute (ANSI)and the国家防火协会（NFPA）(see “Complying With the Many Safety Standards,” below).
跟上这些不断发展的标准 - 每五年刷新，以便跟上技术变化和数据要求 - 可能是一个挑战。此外，尽管正在协调努力，以便对齐ANSI，ISO和International Electrotechnical Commission (IEC), an OEM selling equipment in other countries could encounter additional legal requirements.
“You have to consider the difference between standards and regulations,” explains Fred Hayes, director of technical services atPMMI，包装和加工技术协会。“In the U.S., there is no regulation that tells an OEM how to build a machine. In Europe, there’s a different attitude. They have a machinery directive that tells builders what they must comply with to meet the law.”
But even when everything is done in compliance, there’s still the issue of operator error, which is uncontrollable. In fact, an ANSI standard states “there is no such thing as being absolutely safe, that is, a complete absence of risk. Therefore, there is no machinery that is absolutely safe in the sense of being completely devoid of all conceivable risks.”
And when something happens, who is liable? “In the U.S., the machine owner is responsible for the safety of the machine from a pure OSHA standpoint,” Phoenix Contact’s Stank says, explaining that, once a manufacturer buys the machine, they are responsible for keeping it safe. “But from a civil standpoint, lawyers can go after whoever they want.” That includes the machine builder.
But the standards and the regulations are just one piece of the puzzle, as they are only providing direction for compliance. The second important tool is the technology,罗克韦尔舒斯特说。这包括安全可编程逻辑控制器（PLC），驱动器，伺服和光屏幕等事物。“标准本身不会制造一个安全的系统，”他说。“组件本身不会进行安全系统。他们需要在安全计划的背景下审议。“
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Before building an Urschel machine, a team of engineers conducts a risk assessment to understand how it will be used by the manufacturer, and the required safety measures. |
An integrated effort
Traditionally, safety has been treated separately from the machine controller, the most basic form of safety being hardwired safety relays. But today, with faster, more reliable networks and more processing power, technology suppliers are integrating safety directly into the main PLC.
“In the past, safety has been done with separate controllers,” says Robert Miller, senior PLC/HMI product marketing manager at三菱电动自动化。“现在，随着机器建筑的一部分，安全是一部分，它开始直接集成到控制器中。”
Plus, having one software package to program and troubleshoot makes it easier to monitor and maintain the system. Mitsubishi’s Melsec iQ-R controller has safety built-in, as do the company’s servos, variable-frequency drives (VFDs), and robots. “Building all products to have safety integrated in takes out the complex programming, extra wiring, and extra requirements that safety in the past needed,” Miller says.
Similarly,Beckhoff AutomationTwinSafe集成安全技术，包括I / O终端和软件，可以在EtherCAT网络上传输在同一帧中的安全和非安全数据。安全相关的应用程序配置了Beckhoff的TwinCAT软件，可通过总线系统传输到程序运行的TwinSafe逻辑终端。当数据通过终端时，只有安全终端才能拾取安全数据。“你不必有一个单独的安全网络，”Beckhoff USA的I / O产品经理Sree Swarna Gutta说。“并且您不必担心两个控制面板和控制器，并尝试传达安全和标准PLC的数据。”
The overall goal is to make safety easy and intuitive. For example, Banner’s SC10 safety controller provides the intelligence of a safety controller in a compact, cost-effective device that replaces the functionality of two safety relays. The SC10 uses an icon-based drag-and-drop user interface that allows users to quickly simulate configurations and ensure functionality prior to implementation. “The software also automatically generates wiring diagrams for rapid commissioning,” Klesk says. “Configurations can be saved to a memory card for quick replication across multiple machines without requiring a PC.”
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横幅工程的SC10安全控制器将两个继电器的功能与安全控制器的智能相结合，为较小机器提供了直观，经济高效的解决方案。 |
设计安全
On its machines, Urschel uses IDEM safety switches, Rockwell’s Allen-Bradley guard locking switches, and non-contact switches and safety relays fromPepperl + Fuchs，IDEM,andPilz.
在设计机器时，BOCIAN适用于ISO 13849标准，为设计和集成安全相关部件的原理提供指导，因为它与电路和控制系统有关。他的下一步在安全的设计过程中是研究符合第3类性能水平D的标准。
安全类别范围从1到4,4代表resenting the highest level of safety achieved by the safety function. Categories are about architecture or how the components are put together for a safety function. The performance level (PL), on the other hand, is a technology-neutral concept that can be used for electrical, mechanical, pneumatic, and hydraulic safety. PL is used as a measure of the reliability of the components that make up a safety function and is divided into five levels, A through E, with E giving the best reliability, making it required at the highest level of risk.
“There is a lot of confusion around these designations,” notes PMMI’s Hayes. “A lot of OEMs and end users spend time and money to come up with a control system solution that performs at category 3, level D. But then, I say, look past the end of the wire, because past that, the control system will control a brake on a shaft, which will never be better than category 2.”
The devil is in the details, Hayes says, and that requires that a machine builder use a risk assessment process—even before quoting a job. “First an OEM must understand what a customer wants and how the machine will be used in order to figure out hazards and define safety functions.”
Bocian说，Urschel始终在建设之前进行风险评估。工程集团将分析保护方面，并在构建第一个原型后，他们将组装一支团队来测试系统，并使用DesignSafe软件进行正式风险评估设计安全工程，a software and engineering services company that helps OEMs improve the safety of their equipment.
Designsafe is a tool that walks the user through the process by identifying hazards and then assessing and reducing risk. It identifies who the users are and comes up with built-in checklists. Following that step, the software looks at operator tasks and then the hazards associated with specific tasks from mechanical, electrical to ergonomics, material handling, environmental and more. As builders work through the task list, they can assess the severity of each hazard and how to reduce the risk.
“该软件并没有告诉你要思考的内容，但它可以帮助您对待思考的内容，”设计安全工程总裁Bruce Main说。
Assessing the situation
The safety assessment shouldn’t stop once the machine is built. That’s why Rockwell Automation offers a Safety Maturity Index (SMI) for end users and machine builders. This self-guided online assessment tool measures performance as it relates to culture (behavior), compliance (procedure), and capital (investment in contemporary technology). These measurements can help minimize costs, as well as enhance legal compliance, operator safety, and customer value—which not only optimizes machine design, but can help differentiate machines from the competition, especially with regard to safety and the connected enterprise via the Industrial Internet of Things (IIoT).
“客户已经在过去几十年中制作的网络投资 - 放入工业以太网，例如 - 为数据流提供管道，”罗克韦尔自动化的舒斯特说。“现在，您可以访问数据并具有分析工具来理解它。”
For example, an operator in the plant might have found a better way to perform a task that was never anticipated and that could improve productivity. Alternatively, the misuse of a safety system on the plant floor might be a compliance issue. Collecting information from the machines allows a broader assessment of the situation as it relates to safety functions. Learning that a door is being accessed 40 times per shift when it was only designed for access four times per shift, for example, could indicate that someone is using that door for something they are not supposed to. This might represent a compliance issue, or an opportunity for continuous improvement.
And, while the connectivity and analytics associated with IIoT and Industry 4.0 initiatives might alter the safety processes in place, ultimately, they are providing the kind of diagnostics that will create a safer environment.
“Safety is emerging as a perfectly crafted application space where the connected enterprise or Industry 4.0 can bring people real value,” Schuster says.
