Functional Safety made easy Implementation of the new Directive on machines illustrated by the example of drive monitoring The Kübler Group is one of the leaders in the position and motion sensors branch. Eight group members and 50 sales partners reveal our international orientation. Safety has been for years and still is one of the main focuses of the Company. It is thus no wonder that Kübler is considered today as a pioneer in the area of functional safety. Impressive confirmation: two years ago, this sensor specialist launched the first approved SIL encoder on the market. This was without any doubt a milestone, but the requirements of the European Directives on machines make increasingly obvious that simply combining approved components does not allow reaching the best safety possible. This subject is much too complex. This is why the users are looking more and more for systems for systems from one single source. Kübler reacted to these needs and offers today, with the combination of encoders and safety modules, an efficient global package for functional safety that never existed so far in this form. There are no limits for the applications: safe motion monitoring in single or multi-axes operation, safe processing of light barriers, monitoring of doors and door locks, emergency stop, 2-hand control units the Kübler system ensures simple, fast and cost-efficient implementation of any technical safety task. Safety-M module SP1 The modules are characterised by their high safety standards and integration capability. They are suitable for applications up to PLe according to EN 13849 or SIL3 according to EN 61508. This safe, type-tested logic control complies with the Directive on machines 2006/42/EC.
Furthermore, the Safety-M modules include all integrated safety functions for drive monitoring according to EN 61800-5-2. Thanks to a modular structure and to the interface for all common fieldbus systems, they can be used universally and adapted precisely to the specific requirements. Perfect combination, Safety-M modules with Sendix SIL encoders The Safety-M modules operate ideally when combined with the encoders for Functional Safety SENDIX SIL of the Kübler Company. Three main encoder variants are available: on the one hand, SENDIX SIL incremental with purely sin/cos signals and, on the other hand, SENDIX SIL absolute singleturn/multiturn with additional absolute information SSI. These encoders are approved for use up to SIL3 or PLe. In order to ensure the highest diagnostic coverage possible, the Safety-M modules monitor the sine/cosine signals with the help of the function sin2 + cos2 = 1. And, for a safe position information, even after having been switched off, the safety module compares the internal position provided by the incremental signals with the absolute value of the encoder. Simple and versatile in use The integrated functions for digital signal processing such as sensors, command devices and shut-off channels allow a very comfortable solving of typical safety tasks. But the Safety-M modules offer much more: safe motion monitoring with highest requirements are in no way a problem. And the integrated monitoring functions with many additional practice-oriented functions ensure a simple and transparent implementation of any task. The integrated technology functions of the Safety-M modules ensure a fast and easy implementation of the technical safety tasks. Sendix SIL encoder and Safety-M module SP1 form an effective system for Functional Safety. A comprehensive functions library is available for the preprocessing of sensors (inputs) or actuators (outputs), and it can also be used precisely for safe drive monitoring. A simple combination of the input, monitoring and output functions by means of logic blocks allows a very quick and transparent creation of even comprehensive safety functions. All functions have an open design with respect to the used sensors, drives and actuators. Regardless of the drive technology used, electrical drives with vector or
frequency controls, pneumatic or hydraulic systems, the Safety-M modules are the practice-oriented solution for safety management in mechanical and plant engineering. Safe drive monitoring Safety functions for sensor/actuator processing offer a significant simplification in programming. So, for example, no more programming work is required for a logical/time comparison of multiple safety sensor inputs. Instead, the required process is selected quickly and safely with the periphery configuration menu. The programme editor displays every input and output element simply as a function block. They are already reduced to a single logic signal. Conventional safety controls are restricted to logic processing or reduced word processing of data. A safe drive monitoring as legally required by the European Directive on machines is difficult to achieve this way. In contrast, the Kübler Company placed a particular emphasis with its Safety-M modules on offering devices that will be able to meet future requirements. The safety functions for drive monitoring integrated in the firmware allow for a fast and efficient implementation of new tasks. Regardless of the drive technology used, they offer all functions according to EN 61800-5-2 for drive monitoring and, in addition, practice-oriented function extensions. This applies for single or multi-axes drives, simple converters or high-level servo drives, electrical, hydraulic or pneumatic drives. The safety functions integrated in the firmware are easy to use, whatever the application. Programming, parameterising and validation made easy The graphic programming using symbols has a very simple structure and does not require any specific programming knowledge. After programming, the modules can also be parameterised. One of many possibilities: Safe motion control with two axes. This feature is very practical, especially when a module is to be used for several machine types. Machine-specific parameters can be modified during the assembly or on the field, without requiring any software adaptation. Validating the software also is a part of a safe control. For this purpose, the Safety-M modules print out a validation report, which must be checked, ticked off and signed. This relieves the software manufacturer automatically, since he met his obligation to exercise adequate due diligence.
Abbrevi ation Designation Function SSX Safe Stop 1 or 2 Monitoring of the braking ramp and switch-off of the motor after standstill (SS1) or monitoring of the braking ramp and SOS after standstill (SS2). Corresponds to Stop Category 1 or 2 according to DIN EN 60204-1. SOS Safe Operating Stop Monitoring of the standstill of the active motor. SLA Safety-Limited Acceleration Monitoring of the exceeding of an acceleration limit value. SLS Safety-Limited Speed Monitoring of a speed limit value. SLT Safety Limited Torque Monitoring of a torque / force limit value. SLP Safety-Limited Position The exceeding of a position limit value is monitored. SEL Safe Emergency Limit Safe monitoring of the minimum and maximum position or of the allowed position range. Optional monitoring of the speed/position limit curve for minimising the worst-case travel path. SLI Safety Limited Increment The respect of a specific step value during motion is monitored. SDI Safe Direction Monitoring of the unintended direction of motion of the motor. SBC Safe Brake Control Safe control and monitoring of an external brake. SCA Safe Cam A safe output signal is generated when the motor position is in a specified range. SSM Safe Speed Monitor A safe output signal is generated when the motor speed is lower than a specified value. SAR Safe Acceleration Range Monitoring of the compliance of the motor acceleration within specified limit values. ECS Encoder Status Error status of the speed / position sensor. PDM Position Deviation Muting Muting of the deviation monitoring in case of 2-sensor operation. List of the safe drive functions according to EN 61800-5-2
Connection possibilities of the Safety-M modules. Words: 1197 Photos: 1_Safety_M_MSP1.jpg 2_SIL_encoder_Safety_M.jpg 3_Example-2xSIL-MS2-BM-EN.jpg 4_Safety-M_connection_possibilities-EN.jpg Contact: Stefan Kech, Team Manager Marketing Communication stefan.kech@kuebler.com Tel.: 0 77 20 39 03 79