Machine safety is one of the core responsibilities of a machine builder. In fact, across most geographies, it is the machine builder who is held liable when machine safety systems fail. Machine safety is critical in the eyes of industrial end users, government regulators and the machine builders themselves, who depend on a solid safety reputation in order to compete successfully in the marketplace. Vigilance and attention to detail in the area of machine safety represents a critical success factor for OEMs who wish to preserve and grow their business.
Although safety is critical, for many OEMs, the process of building safety functions into machines can be complex, expensive and tedious. Therefore, manufacturers of machine safety devices and modules, like Schneider Electric, must design solutions that simplify OEM tasks related to building safety functions into machines.
End-to-end safety solutions provide machine builders with coordinated input devices (such as e-stops or light curtains), processing devices (such as new generation Schneider Electric Harmony XPS safety modules) and output devices (such as contactors, variable speed drives or servo drives). Working together, these three safety chain components can be treated as one safety function within a particular machine.
Addressing the stringent regulation challenge
The most important machine-safety related industry standards are usually updated and refreshed every 5-6 years. With every new set of standards, the safety demands on both OEMs and industrial end users increase and become more complex to implement.
Europe has traditionally been a leader in machine safety, and now European-style safety directives (with some modifications) are beginning to be enforced in major countries like China and Brazil. Globally, the trend is moving towards the development of stronger safety standards and the more aggressive enforcement of those standards.
Those who do not strictly conform to standards face a high risk when an accident occurs. In such cases, the authorities investigate and determine machine compliance. If the machine builder is found negligent, fines can be levied and the reputation of the machine builder is negatively impacted.
An important aspect of regulatory compliance is the performance of a proper safety risk assessment. These assessments are performed by a team of qualified individuals. In many cases, machine builders will enlist the services of a consultant to perform the assessment. Machines which appear on the regulatory directives hazardous machines list must be certified by a recognized and authorized body (like the Technical Inspection Association in Germany, or UL in the United States).
How Schneider Electric safety devices simplify OEM machine safety challenges
In response to these demanding OEM machine safety environments, Schneider Electric has introduced a new generation of single function module safety devices for use in both optimized and performance machines (but rarely in high performance machines). Known as the Harmony XPS safety modules, these devices support machine builder safety implementations in four important ways: they help to enable faster certification, ease commissioning, provide superior diagnostics, and facilitate spare parts management.
- Certification – Schneider Electric is the first company to create certified safety chain solutions. Within the Harmony XPS safety modules there are several models that qualify as pre-certified safety chain documents. As these documents are already certified, they quickly pass through risk assessment and provide the documentation needed so that OEMs don’t have to spend valuable time creating and assembling the needed technical information.
- Commissioning – Since the new generation of safety processing devices are more intelligent and are able to monitor input and output devices connected, machine safety commissioning is faster and easier. The module recognizes if the configuration and the connected input device for instance are not matching. As a result, accurate indications and corrective reconfigurations can be made quickly.
- Diagnostics – Traditional safety module devices are capable of outputting only a very limited amount of diagnostic information. They communicate that safety contactors are open but don’t explain why, for example. They also require a very expensive field bus connection. Now, through one single hard-wired connection to a standard input of a PLC, the Harmony XPS Universal safety modules can communicate up to 43 diagnostic messages to the operator. One example of a new message in a manual start situation is “module is waiting for start button to be pressed.” Or, in the case of a time-delayed output example, when the e-stop is pressed, the module turns off the immediate normally open contacts and informs the machine operator that the time delayed outputs are still closed. The diagnostic messages also point out if there are issues in the input or output feedback circuitry. No other manufacturer provides that level of detail through a single hard-wired connection.
- Spare parts management and inventory control – In rolling out its new line of Harmony XPS safety modules, Schneider Electric has simultaneously reduced the number of references from 64 to 28 and has provided a wider range of voltage options for all of the references In addition, in the new devices, the terminal variants have been harmonized to a removable screw and spring terminal design. The two voltage options include both 24 volts AC/DC and a range from 48 to 240 volts AC/DC. The fewer references make it easier for OEMs to order the parts. In addition, fewer stock items will be required which will drive down inventory cost while speeding up spare parts delivery and service.
Modern machine safety devices are just one example of the many ways Schneider Electric can help OEMs drive design, installation, commissioning and operation efficiencies of their machines. For a deeper understanding of how new safety chain input, processing and output devices can improve machine builder productivity and peace of mind, visit https://www.schneider-electric.com/en/work/campaign/smart-machines/safety.jsp