One-stop sensor and control technology
Safety gates, covers and flaps safeguard access to plant and machinery. In particular they provide protection against hazardous movements of plant and machinery or from flying parts. The challenge for design engineers is to choose the right solution from the wide range of safety switches, guard locking devices and safety gate systems available.
When selecting the right components for safe monitoring of moveable guards, there are various questions that need to be answered, such as: Does it involve a gate, cover or flap which is regularly opened and closed? Does the process need protecting as well as the operator? Are components exposed to heavy soiling, strong vibration and extreme temperatures?
David Collier, Business Development Manager at Pilz Automation discusses the different applications where Pilz’s wide range of safe sensors could be used.
Mechanical safety gate switches
Mechanical safety gate switches are suitable for safety gate monitoring or guard locking functions on simple safety gate applications, where there are no increased requirements for protection against manipulation and defeat. They prevent a safety gate, cover or flap being opened unintentionally, thanks to increased actuator extraction force.
The combination of safety switch, handle and bolt is particularly suitable for safety gates that are difficult to adjust or in areas where safety gates are opened and closed frequently, as the actuator is mechanically guided into the switch actuator head. Pilz’s safety bolt PSENbolt offers the safe, complete solution comprising safety switch, handle and bolt, removing the need for expensive in-house engineering.
Non-contact safety switches
Non-contact safety switches are becoming increasingly important, particularly on machines that are operated frequently and are exposed to heavy vibration. As the response tolerance is generally high, these switches are flexible and easy to install on the machine.
Non-contact safety switches distinguish between two operating principles: magnetic safety switches with normal manipulation protection and coded safety switches with high manipulation protection. What’s more, with the Pilz safety switches PSENmag and PSENcode it is possible to achieve PL e of EN ISO 13849-1, SIL 3 of EN/IEC 62061 and Cat. 4 of EN 954-1.
Additional process protection for increased requirements
Many doors, covers or flaps must be opened more frequently for operational or assembly purposes. The disadvantage of mechanical guard locking devices is that the adjustment has to be as precise as possible.
For this type of requirement Pilz offers the PSENslock, a non-contact, coded safety switch with a magnetic interlock of 500 N or 1000 N, all in one system. With this combination of safe position monitoring and process guard locking, PSENslock provides a safe alternative to existing mechanical technology. A high level of protection against manipulation and defeat, combined with low wear and tear, ensure a long service life.
Integrated systems save time and money
The safety gate system PSENsgate from Pilz relies on a combination of electronics and mechanics. It meets the requirements of the very highest category in just one system. The compact safety gate system combines safety gate monitoring, safe guard locking and control elements, including additional functions such as E-STOP and escape/auxiliary release. As the system also detects broken pins and broken bolts, it offers additional safety for machinery with a particularly high hazard potential. Complete systems such as these are mostly used on larger safety gates.
Safety even without guards
As safeguards on plant or machinery access points and danger zones, light curtain devices such as the PSENopt provide finger, hand or body protection in accordance with EN/IEC 61496-1/-2. Advanced functions such as muting, blanking ad cascading can be achieved quickly and easily using the intuitive configuration software PSENopt Configurator.
Static or one-dimensional safeguards can reach their limits, particularly on robot applications. New, camera-based processes, such as those used by the safe camera system SafetyEYE for zone monitoring or the camera-based, mobile protection system PSENvip for press brakes, can monitor protected fields and detection zones safely in 3D. These sensor systems from Pilz interact with the evaluation function via safe communication channels and guarantee optimum plant productivity.
Increasing automation in mechanical engineering means that the demands on machine safety are also rising. The issues of availability, cost-effectiveness and process safety must all be accommodated. Design engineers have access to a wide range of sensors for safety gate monitoring. These operate to different principles and offer a variety of design options for safe, but user-friendly solutions. After all, if the machine is not user-friendly, manipulation of safety equipment is inevitable.