This article reviews the basics of safety circuits for automated machinery. The discussion will touch on standards that dictate required features; common setups; mechanisms for addressing faults and preventing tampering; and the functions of components often found in safety-circuit installations.
interdependent — are core to the function of today’s safety systems. These prevent machines from injuring operators or damaging their own components. For example, an interlock may prevent a machine from starting if its guard is open and stop the machine if a guard is opened during operation. Many simple interlock systems are purely mechanical. For example, in some machine designs, the guard pivots about an axis with an interlock cam attached. When the guard is open, the cam engages with a matching cam on the machine’s drive shaft to prevent operation of the axis. That means it’s only possible for the machine to operate when the guard is closed.
History and function of safety circuits In the early industrial period, machinery was extremely
dangerous. It was common for both factory and agricultural workers to lose fingers, limbs, and even their lives through entrapment in moving machinery. This led to the development of systems of guarding and other safety devices. Interlocks — which make the state of two or more machine functions
Most modern machines use electronic safety circuits or even microprocessor control to implement interlock safety
Basic understanding of safety circuits
By Lisa Eitel Contributed By DigiKey's North American Editors
we get technical
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