Q & A: Can Safety PLCs be used for Lockout?

Disconnect Switch with Lock and Tag
This entry is part 2 of 2 in the series Q & A

The ques­tion of lock­out and the use of safe­ty PLCs as a means to meet the lock­out require­ments comes up more and more fre­quent­ly these days. Can Safe­ty PLCs be used for lock­out? Safe­ty pro­fes­sion­als don’t always agree on this con­tro­ver­sial top­ic!

Dur­ing the Free Safe­ty Talks that we did with Schm­er­sal Cana­da and Franklin Empire, this hot ques­tion came up, so I thought I’d cov­er it off in a video. If you need some spe­cif­ic help with an appli­ca­tion like this, please get in touch with Doug direct­ly.

There is a lot to say, and in this video I try to cov­er off the rea­sons why Safe­ty PLCs and Lock­out don’t always mix well.

Notes

Ontario Reg­u­la­tion 851, Indus­tri­al Estab­lish­ments

CSA Z432, Safe­guard­ing of Machin­ery

CSA Z460, Con­trol of haz­ardous ener­gy – Lock­out and oth­er meth­ods

ISO 13849–1, Safe­ty of machin­ery — Safe­ty-relat­ed parts of con­trol sys­tems — Part 1: Gen­er­al prin­ci­ples for design

ISO 13849–2, Safe­ty of machin­ery — Safe­ty-relat­ed parts of con­trol sys­tems — Part 2: Val­i­da­tion

IEC 62061, Safe­ty of machin­ery — Func­tion­al safe­ty of safe­ty-relat­ed elec­tri­cal, elec­tron­ic and pro­gram­ma­ble elec­tron­ic con­trol sys­tems

IEC TR 62061–1:2010, Guid­ance on the appli­ca­tion of ISO 13849–1 and IEC 62061 in the design of safe­ty-relat­ed con­trol sys­tems for machin­ery

Ques­tions? Leave a com­ment below or email Doug.

Series Nav­i­ga­tion& A: Cat­e­go­ry 2 and Test­ing Intervals”>Q & A: Cat­e­go­ry 2 and Test­ing Inter­vals

Author: Doug Nix

Doug Nix is Managing Director and Principal Consultant at Compliance InSight Consulting, Inc. (http://www.complianceinsight.ca) in Kitchener, Ontario, and is Lead Author and Senior Editor of the Machinery Safety 101 blog. Doug's work includes teaching machinery risk assessment techniques privately and through Conestoga College Institute of Technology and Advanced Learning in Kitchener, Ontario, as well as providing technical services and training programs to clients related to risk assessment, industrial machinery safety, safety-related control system integration and reliability, laser safety and regulatory conformity. For more see Doug's LinkedIn profile.