Machinery safety a top priority for Pilz Automation

Company says category 3 or 4 architecture must be used to achieve maximum safety performance level PLe

IN order to achieve the maximum safety performance level PLe, a category 3 or 4 architecture must be used. What this means in the case of a servo system is that a second method for measuring speed is required; and this, say Pilz Automation, is commonly achieved by fitting an additional separate encoder or resolver to the axis, increasing the costs and complicity of the system and set-up process.

The PMC Protego DS safe motion drive from Pilz has been designed to measure the motor current to determine its speed, thanks to its on-board safety card. This, combined with the feedback signal provided by the servo motor, constitutes a category 4 architecture.

This means that using the PMC Protego DS drive and any servo motor; it is possible to achieve PLe safety performance level without any additional equipment.

The Pilz drive also offers the following ‘safe motion functions’ as standard: safe torque off; safe stop 1; safe stop 2; safe operating stop; safe limited speed; safe speed range; safe direction; and safe limited increment. Safe braking functions and safe limited position are available as additional options.

With free configuration software included, the PMC Protego DS solution is said to be easy to configure for motion tasks and safety features alike.