Potective equipment for machines and plants are often protected by mechanical safety switches, which are typically connected in series especially where multiple safety doors are concerned. Here the requirement of the Machinery Directive, according to which every plant must be equipped with an emergency stop device, has to be considered. In addition, fault masking* is an often-underestimated problem which has to be thought of to avoid danger to the machine operator. With the Safety Emergency Unit, (SEU) BERNSTEIN has developed a simple electronic solution that makes both challenges a thing of the past.
Thanks to the M12 connection, the Safety Emergency Unit can be easily integrated into an existing electronic SRF daisy chain. The requirements of the Machinery Directive, according to which every plant must be equipped with an emergency stop device, are thus fulfilled. And the problem of fault masking no longer exists due to this electronic solution. "Together with the SRF Smart Safety Sensor, the SEU forms the optimum total package, a Smart Safety System, for the electronic monitoring of safety guards," says Philip Aumann, BERNSTEIN product manager.
First of all - despite series connection - the large LED display quickly shows which emergency stop has been activated. Each device in this Smart Safety System provides a wide range of data for intelligent production, enabling predictive maintenance. These are made available via the DCD system, which transmits the data of all sensors and emergency stop devices connected in series to the control system via IO-Link. This allows early fault detection and avoids costly downtime or even damage to the machine.