Machine guarding and economic value: Wired safety versus safety automation

Over the past 10 years machine safety has experienced probably the greatest transformation since the advent of machine control technology. In my opinion, the recent adoption of “safety automation” has outpaced the original adoption of PLC technology in the early 1970’s. It was in the early 1970’s that machine safety was mandated by industry standards to be “hard wired.” At this time, PLC technology had just been introduced, and its reliability paled in contrast to the robust PLC reliability of today. See graph illustrated below.

10/31/2011


Machine safety has experience probably the greatest transformation over the past 10 years since the advent of machine control technology. In my opinion, the recent adoption of “safety automation” has outpaced the original adoption of PLC technology in the early 1970s. It was in the early 1970s that machine safety was mandated by industry standards to be “hard wired.” At this time PLC technology had just been introduced and its reliability paled in contrast to the robust PLC reliability of today. Just take a quick glance at the conceptual graph illustrated below.

Graph explaining the growth of general automation versus machine safety technology along with downtime. Courtesy: J.B. Titus 

I experienced the introduction of automation technology lead by PLCs as a young engineer in an automotive plant. After a slow start, automation technology took off like a rocket experiencing wide spread adoption and application to machine control. The advantages of diagnostics reduced wiring, increased machine up-time, reduced panel space, easier trouble shooting, etc. drove acceptance as research and development drove technological improvements and inherent reliability. At the same time, however, machine safety was required to be hard wired and could not enjoy these advantages or technological improvements.

JB Titus, CFSEIn my opinion, this created a safety layer in the machine control architecture interfacing the safety related electromechanical components to the machine control automation technology. The unintended consequences resulted in a rather stagnant level of technology innovation for the safety layer in comparison to the automation technology. This gap of technology helped drive a new metric called “unplanned downtime.” Plant operation personnel became used to the diagnostics and other advantages of the automation technology and conversely became frustrated by the lack of diagnostics, intermittent downtimes, and other disadvantages of the safety layer. Thusly, many of us experienced occasions where “quick fixes” were made to get machines back into production to meet schedule demands.

To make a long story short, folks in my era have experienced the changing landscape of machine control to once again see the unified machine control architecture of “integrated automation with safety” in innovative technology. Machine safety can once again be designed in vs an after-thought. Of course, direct wiring of safety components is still a viable option. However, for larger more complicated machines integrated safety is now available. Most importantly the economic values of increased productivity can drive increased profits which in turn can provide a competitive advantage.

What experiences have you had along this changing landscape evolution?

Your comments or suggestion are always welcome so please let us know your thoughts. Submit your ideas, experiences, and challenges on this subject in the comments section below. Click on the following text if you don't see a comments box, then scroll down: Machine Guarding & Economic Value – wired safety vs safety automation

Did you see the Safety Integration Webcast?

Related articles:

Cost Savings Opportunities in Machine Safety

Machine Safety Pays

Risk assessment - A best practice for sustainable performance

Machine safety pays off

Contact: www.jbtitus.com for “Solutions for Machine Safety”.



No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
Each year, a panel of Control Engineering editors and industry expert judges select the System Integrator of the Year Award winners.
Control Engineering Leaders Under 40 identifies and gives recognition to young engineers who...
Learn more about methods used to ensure that the integration between the safety system and the process control...
Adding industrial toughness and reliability to Ethernet eGuide
Technological advances like multiple-in-multiple-out (MIMO) transmitting and receiving
Virtualization advice: 4 ways splitting servers can help manufacturing; Efficient motion controls; Fill the brain drain; Learn from the HART Plant of the Year
Two sides to process safety: Combining human and technical factors in your program; Preparing HMI graphics for migrations; Mechatronics and safety; Engineers' Choice Awards
Detecting security breaches: Forensic invenstigations depend on knowing your networks inside and out; Wireless workers; Opening robotic control; Product exclusive: Robust encoders
The Ask Control Engineering blog covers all aspects of automation, including motors, drives, sensors, motion control, machine control, and embedded systems.
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
News and comments from Control Engineering process industries editor, Peter Welander.
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
This is a blog from the trenches – written by engineers who are implementing and upgrading control systems every day across every industry.
Anthony Baker is a fictitious aggregation of experts from Callisto Integration, providing manufacturing consulting and systems integration.
Integrator Guide

Integrator Guide

Search the online Automation Integrator Guide
 

Create New Listing

Visit the System Integrators page to view past winners of Control Engineering's System Integrator of the Year Award and learn how to enter the competition. You will also find more information on system integrators and Control System Integrators Association.

Case Study Database

Case Study Database

Get more exposure for your case study by uploading it to the Control Engineering case study database, where end-users can identify relevant solutions and explore what the experts are doing to effectively implement a variety of technology and productivity related projects.

These case studies provide examples of how knowledgeable solution providers have used technology, processes and people to create effective and successful implementations in real-world situations. Case studies can be completed by filling out a simple online form where you can outline the project title, abstract, and full story in 1500 words or less; upload photos, videos and a logo.

Click here to visit the Case Study Database and upload your case study.