© Exportpages.com
Malfunctions or failure of machines and equipment may lead to personal injury or damage to environment or property. The safety standards IEC 61511 and IEC 61508 assess facilities and risk-counteracting steps assessed into four safety categories, from SIL 1 (inferior risks) to SIL 4 (high risks). The higher the risk, the more painstakingly must be the precautions and the more reliable the components utilized. This applies consequently also to encoders which so far used to be the 'weakest link' in the chain of safety precautions. In the absence of existing approvals the only alternative used to be adequate auxiliary concepts under supervision of technical authorities. Now things have changed. By G1S2B BaumerIVO presents a safety-relevant multiturn absolute encoder featuring two redundant interfaces (SIL3 approved) especially intended for use in theatre stage technology, at cranes and suspension railways.
Technical appliances always imply a certain risk regarding safety since any malfunction might endanger persons or result in damage of environment or property. Specific safety standards are to be observed already in the design stage of such appliances to keep risks down to a minimum. However, the true consequences for practical use in factory automation are not always immediately evident. First of all there is the definition of the term 'safety'. In Anglo-Saxon meaning for example 'safety' and 'security' are not the same. Latter means protection against attacks whereas 'safety' implies precautions against events like failure of system or equipment, wear and tear, errors in operation – in short preventive actions against 'technical or human errors'. This difference does not exist in the German meaning but it is a general expression for a state or situation free from risk and danger.