5.11 Safety Function5-855 Operation5.11.3 Application Example of Safety FunctionsAn example of using safety functions is shown below.(1) Connection ExampleIn the following example, a safety unit is used and the HWBB function operates when the guard opens.When a guard opens, both of signals, the /HWBB1 and the /HWBB2, turn OFF, and the EDM1 signal is ON.Since the feedback is ON when the guard closes, the safety unit is reset, and the /HWBB1 and the /HWBB2signals turn ON, and the operation becomes possible.Note: Connect the EDM1 as the direction of current flows from EMD1+ to EMD1-, because the EMD1 has polarity with atransistor output.(2) Failure Detection MethodIn case of a failure such as the /HWBB1 or the /HWBB2 signal remains ON, the safety unit is not resetbecause the EDM1 signal keeps OFF. Therefore starting is impossible, then the failure is detected.An error in the external device, disconnection or short-circuiting of the external wiring, or a failure in theSERVOPACK must be considered. Find the cause and correct the problem./HWBB1+SERVOPACKCN8436587A1A2T11 T12 T21T31 T32 T33 S24OutputS14T22/HWBB1-/HWBB2+/HWBB2-EDM1+EDM1-24 VPowersupplyGuardSafety unitmanufacturedby OMRON Corp.G9SX-BC202Fuse0 VCloseLimit switchPowersupplyinputInputReset/feedbackinputOpen
