Page 81 - ENGINEERING REVIEW APRIL 2022 DIGITAL MAGAZINE

TECH INNOVATION
#SAFETY CONTROLLERS

separated solution One of the positives If the higher-level safety concept is Protect Select small safety controller
of standalone safety infrastructure is based on a safety integrated solution, has been specially developed for this
the fact that a safety concept can be machinery and subsystems that operate very application. The user does not
accomplished independently of the in standalone mode can often only be have to program the controller but can
automation solution and, therefore, operated in a rudimental manner. On the choose from pre-configured programs
independently of the manufacturer of other hand, a compact safety controller and only has to enter the corresponding
the functional control system that may like the Protect PSC1 from Schmersal parameters. These applications cover
be specified by the machinery builder. offers a simple and flexible option by a wide range of possible use cases.
Consequently, even when customer- means of integrated safety protocols Additionally, the user can also activate
specific automation PLCs are used, a (Profisafe and FSoE) to operate such special features such as free allocation
standardised safety concept can be machinery encapsulated and, if required, of feedback circuits (EDM), start-up
accomplished on an always identical to integrate them into fail-safe fieldbus tests, cyclical testing and auto-start with
component and hardware basis. architectures without having to make every program. Additional functions and
Another benefit is that you do not need changes to the safety application. operating modes (setup mode, process
to be a PLC specialist to program the monitoring) can also be accomplished.
safety functions – the range of language Compact and complete
is manageable when compared to Manufacturers of smaller machines Modular compact safety controller
automation control systems. in particular are increasingly having If a higher level of customisation and
to confront more stringent safety adaptability is required, the Protect PSC1
Integration option requirements. In addition, the expectations safety PLC could be an option. Thanks to
Opting for separate safety does not of end customers in terms of diagnosis its modular design, it is easy to adapt to
mean that integration is impossible. options and ease of maintenance are user requirements, irrespective of whether
Quite the opposite in fact. Bus protocols also on the increase in this segment. This the signals from emergency-stop control
enable integration into higher-level requirements profile can be mapped easily devices, electromechanical safety switch-
control systems, something which might and cost-effectively with a small safety gear, tactile protective devices, safety
be required when production systems controller. Depending on the application, sensors or optical protective devices need
comprising multiple subsystems from standard automation can also be realised to be evaluated. A number of modules
different providers need to be integrated. with the small controller, and integration are available for fail-safe drive monitoring,
In that case, the safety solutions of the can be achieved ‘in the opposite direction’. which reliably monitor parameters includ-
individual system must be connected The Schmersal Group offers two ing position, speed and increment.
in order to implement a higher-level options to help achieve a safety separated Additionally, the controller can also
emergency-stop function, for example. concept on smaller machinery. The be supplemented with a universal
communication interface, where the
user simply selects and sets various bus
protocols such as Profinet, Ethercat,
Ethernet/IP, Profibus or CANopen using
software. The interface also allows
safety remote I/O communication and the
simultaneous connection of up to four
systems via safety cross communication
via Ethernet. An OPC UA server can
also be integrated. In summary, a
safety separated safety concept can
offer significant benefits in terms of
standardisation, operating convenience
and flexibility.

For more information,
Fig. 2: The Protect PSC1 safety controller enables the realisation of ‘safety
separated’ solutions. It also enables integration into higher-level infrastructure. Website: www.schmersal.in

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