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EN 13849-1 and the functional safety

Safety standards define safety as freedom from unacceptable risk. The most effective way to eliminate risks is to design them away. But as risk reduction by design is not always possible or practical, safeguarding with static guards are often the next best option, and for several reasons. 
Stopping a machine quickly and safely, not only reduces risk but also increases machine uptime and productivity compared with abrupt safety stops. At the same time, the legal obligations are met and the safety of people and
the environment is ensured.

Functional safety in machinery usually means systems that safely monitor and, when necessary, override the machine applications to ensure safe operation. A safety-related system thus implements the required safety functions by detecting hazardous conditions and bringing operation to a safe state, by ensuring that a desired
action, e.g. safe stopping, takes place.

The concept of Functional Safety was introduced by the IEC 61508: "Functional Safety of Electrical/Electronic/Programmable Electronic Safety-related Systems"

Machineriy Manufacturers normally refer to the EN 62061 and more often to the EN 13849-1 when they need to assess the Performance Level of their Safety Systems. The software SISTEMA, free for download from the dguv.de web site, helps in this task. 

GT Engineering, together with the Università di Brescia, has developped a methodology compliant with the EN 13849-1 that assesses the PL of a certain safety logic. Being a methodology and not a software is intuitive and practical to use. If you would like to know more, please do not hesitate to contact us.

If you deal with Machinery Safety you may wonder what Whole Body Access means. That is a relatively new terminology (this article was written in 2019). It indicates the risk that a person remains inside a safeguarded space. Exposure to a hazard represents a potential risk when a person gains access to a hazard zone beyond a safeguard space.   A hazard arises when the person is no longer detected and the hazardous situation machine function resum
Machinery safety
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Arc Flash
The Earth Fault Loop includes the Load, the bonding conductor, the earthed (Grounded) neutral point of the tranformer, the source line winding and the live conductor from the source to the load. The earth fault loop impedance verification is performed to prove the correct operation of the protective device in order to protect in caso of indirect contats. The aim is to check that, in case of a ground fault, the related fault current is strong eno
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Arc Flash
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Arc Flash
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Machinery safety
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Machinery safety
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UL and CSA Conformity
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Gas Fournaces CE Marking
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Arc Flash
Currently the NEC in Article 100 defines the terms "ground" or "grounded" as "connected to the earth or to some conducting body that serves in place of the earth." Yet, the NEC often uses the term "ground" when it really means "bond" (connected to an effective ground-fault path to clear a fault) [250.2 and 250.4(A)(5)]. The two concepts have quite different meaning. Grounding - Grounding metal parts to the earth in premises wiring is only useful
Machinery safety
Occupational Safety and Health Administration (OSHA) The Occupational Safety and Health Act (OSHA) passed in 1970 to provide safe and healthy working conditions. Part 1910 of the 29th Code of Federal Regulations (CFR) gives specific standards. Subpart O of Part 1910 sets standards for machinery and machine guarding, and divides into Part1910.211 to Part 1910.219. Standard No.   Title 1910.211          Definition 1910.212          General requir
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The reference standard in Canada for the Machinery Safety is the Technical Norm Z432-04. This Standard is intended to be applied to newly manufactured and newly installed machinery. The aim of this Standard is to promote a high standard of machinery safety during use.  It specifies requirements for the design, manufacture (including remanufacture and rebuilding), installation, maintenance, operation, and safeguarding of industrial equipment to 
Machinery safety
Safety standards define safety as freedom from unacceptable risk. The most effective way to eliminate risks is to design them away. But as risk reduction by design is not always possible or practical, safeguarding with static guards are often the next best option, and for several reasons.  Stopping a machine quickly and safely, not only reduces risk but also increases machine uptime and productivity compared with abrupt safety stops. At the same 

Safety in Collaborative Robotics

There is no “Collaborative Robot”. That is one of the first statements you hear from people working in Collaborative Robotics. The reason is because the robot can be designed for a collaborative task, but it is the Application that makes the “Robot Collaborative”. The reference standard for Collaborative Application is  ISO/TS 15066:2016 - ROBOTS AND ROBOTIC DEVICES -- COLLABORATIVE ROBOTS Not only for the unfortunate title, the standard will be included in the new edition of 2 important standards on Robots: ISO 10218-1: Robotics — Safety requirements for robot systems in an industrial envir