Machine safety: What does 'reset' mean?

Who hasn’t heard the term “reset” around machine control? And, how many understandings are there from machine builders to machine users? What do standards think about the term?


Who hasn’t heard the term “reset” around machine control? And, how many understandings are there from machine builders to machine users? Oh, and what about the standards writers?


Jokab Safety giant E-Stop at Pack Expo 2010

My first thought on this subject was to look in several current standards to see how the term “reset” was defined. Much to my surprise “reset” was not listed with a definition. However, many standards describe within their document how to perform a “reset” – but of what?


Secondly, in my opinion, I thought of what folks have described over the past 20 years or so: 

Manufacturers (users) – they have described “reset” as having to do with  resetting the control system to a run mode typically after an emergency stop condition. 

Machine Builders – they often talk about resetting the stop function to allow another mode like run, micro-inch, set-up, etc.  

Component Suppliers – sometimes they talk the required push and twist action of resetting their e-stopping device.  

Control System Suppliers – they, however, often talk about resetting the control system to production mode whether the “reset” of a stop/e-stop was caused by a device or the machine control logic. 

Standards (and writers) – these documents often describe the required steps involved in re-energizing the control system/motion to run production following various types of stopping conditions including some typical precautions and informational references.


In my opinion, ANSI B11.19-2010, Performance Criteria for Safeguarding, represents a very up to date and comprehensive approach to the requirements surrounding “reset”. Clause 6 in particular has an excellent Table that offers explanatory comparisons of three primary functions; Stop, E-Stop and Protective (Safety) Stop. This standard also does a great job of referencing other Standards like NFPA 79 – 2012, Electrical Standard for Industrial Machinery, as well as other ANSI Standards and reference materials.


It’s probably fair to say that the best understanding of “reset” comes from several of the latest machine guarding standards and several years of practical experience in combination with your specific type(s) of machinery and control systems.     


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 Safety: What does 'reset' mean?



J.B. Titus, CFSERelated reading and articles:

ANSI B11.19-2010, Performance Criteria for Safeguarding

NFPA 79 – 2012, Electrical Standard for Industrial Machinery

E-Stops and Your Compliance

E-Stops Aren’t Safety Devices


Contact: 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...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Learn how to create value with re-use; gain productivity with lean automation and connectivity, and optimize panel design and construction.
Machine design tips: Pneumatic or electric; Software upgrades; Ethernet advantages; Additive manufacturing; Engineering Leaders; Product exclusives: PLC, HMI, IO
Industrial wireless cyber security: More complex than black and white; IIoT at the I/O level; Process modeling; Cyber security research
Robotic advances: Software, form factors; System-based ROI; Embedded control; MES and information integration; SCADA and cyber security; Position sensor; Controller, I/O module
Learn how Industry 4.0 adds supply chain efficiency, optimizes pricing, improves quality, and more.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Drilling for Big Data: Managing the flow of information; Big data drilldown series: Challenge and opportunity; OT to IT: Creating a circle of improvement; Industry loses best workers, again
Pipeline vulnerabilities? Securing hydrocarbon transit; Predictive analytics hit the mainstream; Dirty pipelines decrease flow, production—pig your line; Ensuring pipeline physical and cyber security
Cyber security attack: The threat is real; Hacking O&G control systems: Understanding the cyber risk; The active cyber defense cycle