Complementary Protective Measures

Emergency Stop Pull-Cords

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This entry is part 14 of 14 in the series Emer­gency Stop

When it comes to emer­gency stop devices there is no doubt that the red mush­­room-head push but­ton is the most com­mon – they seem to be every­where. The second most com­mon emer­gency stop device is the pull-cord, and like the light-cur­­tain in safe­guard­ing, the pull-cord is prob­ably the most mis­ap­plied emer­gency stop device. Copy­right secured by Digi­prove © 2018Acknow­ledge­ments: As cited […]

Emergency Stop

Emergency Stop Failures

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This entry is part 13 of 14 in the series Emer­gency Stop

I am always look­ing for inter­est­ing examples of machinery safety prob­lems to share on MS101. Recently I was scrolling Reddit/r/OSHA and found these three real-world examples. Broken Emer­gency Stop But­tons The first and most obvi­ous kinds of fail­ures are those res­ult­ing from either wear out or dam­age to emer­gency stop devices like e-stop but­tons or pull […]

Canada

Safe Drive Control including Safe Torque Off (STO)

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Graph illustrating STO Function
This entry is part 12 of 14 in the series Emer­gency Stop

Ed. Note: This art­icle was revised 25-Jul-17 to include inform­a­tion on safe stand­still. Safe Drive Con­trol includ­ing STO Motor drives are every­where. From DC vari­able speed drives and index­ing drives, through AC Vari­able Fre­quency drives, servo drives and step­per motor drives, the cap­ab­il­it­ies and the flex­ib­il­ity of these elec­tron­ic sys­tems has giv­en machine design­ers unpre­ced­en­ted […]