Safe limit value specification

Safe motion monitoring requires not just safe motion detection but also the opportunity to specify limit values safely. The way in which this is achieved depends on the level of dynamics and the flexibility within the machine.

Relay-like systems often use constant limit values. For example, a fixed limit value can be defined by setting jumpers or via other setting options on the device. On safe control systems, multiple limit values can be defined via configuration or programming user interfaces. Selection can be made during operation via a safe I/O interconnection, through evaluation of sensor signals or through specification via a safe fieldbus, for example. Dynamic limit values can only be used in conjunction with a powerful, safe control system or a safe bus system with real-time capabilities. When combined with optical monitoring of the protected field in robot
applications, for example, safe speed can be reduced based on the distance of the operator from the danger zone: the closer the operator comes to the danger zone, the slower the motors move.

Robotics Industry can use InduraNET p for wireless communication needs

These days robots have successfully established themselves in a wide range of industrial applications. Whether it's the automotive industry, packaging technology or sheet metal working: industrial robots play an ever increasing role. The increasing level of automation within production processes is promoting the widespread use of robots.

The robotics industry needs a reliable, wireless transmission of standard I/O data to mobile plant or machine sections. The wireless system InduraNET p (Industrial Radio Network) from Pilz is specifically designed for use in an industrial environment.  The remote IP67 module is ideally suited for use on robots (installed on the tool, close to the process). As a result, cable wear and open circuit can be avoided; even dust and water cannot damage the module.

Pilz’s InduraNET p is especially suitable for use in an industrial environment. Key features include high availability thanks to the robust communication technology and a unique antenna system, plus the ability to coexist with other wireless systems. Thanks to its rugged design, the IP67 remote module is suitable for installation close to the process, directly on the sensors. This is important so manufacturers can avoid long cable routes and reduce cable wear.

A connection to all common fieldbus systems means that InduraNET p can be incorporated into existing network architectures. This guarantees a high degree of flexibility when selecting the fieldbus and control system.

Some of InduraNet p’s benefits include:

• Highly available wireless communication in an industrial environment via the InduraNET p protocol and industrial antenna system

• Direct assembly on mobile machine parts – due to a high resistance to dirt and mechanical stress, plus a suitable antenna

• Space-saving application outside the control cabinet – IP67 protection

• Licence-free, uses the free worldwide ISM frequency bands

• Solves the problems of cost-intensive, wearing cable connections

• Connection to all common fieldbus systems

InduraNET p can replace data light beam devices, trailing cables/ cable drag chains, and sliding contacts.

Safety-Related and Non-Safety-Related Communication

Communication on contact-based safety relays is very limited. Simply displaying fault conditions can sometimes prove difficult. Switching to electronic versions already makes communication somewhat easier: LEDs flash, sometimes with varying frequencies, to distinguish between specific malfunctions. LCD displays indicate errors and/or operating states in plain text. Configurable safety relays offer a whole new set of options: Fieldbus modules can be used to connect them to almost any fieldbus; they can even exchange safety-related data via special interconnection modules. This enables data to be exchanged with non-safety-related fieldbus subscribers, in order to share diagnostic data or transfer control commands to the configurable safety relay, for example.

The ability to transfer data safely via special interconnection modules opens up new horizons: If several machines are working together in a network, for example, safety requirements will demand that safety signals are exchanged between the control systems. Previously this could only be achieved by exchanging digital signals. This is a laborious process and is extremely inefficient due to the high cost for each piece of information transmitted. If interconnection modules are used to replace the previous hard-wired solution; the
amount of wiring is reduced, while the amount of information data, including safety technology data, is  increased.