November 19, 2013 By Kristina Urquhart
One important part of machine safety is the associated electrical approval for installation in operating environments. A new standard from IEC — IEC 61010-2-201, “Safety requirements for electrical equipment for measurement, control and laboratory use” — will impact the way these approvals are made and, therefore, is something that is likely to affect the way you specify and purchase control equipment.
The plan by the IEC and ISO is to provide a single set of certification standards for industrial control equipment within a new certifying body (CB) scheme. The new “Industrial Automation” category will be identified as INDAT (INdustrial Distributed Automation Technology).
The CB scheme was created to facilitate global trade through the use of IEC standards and, as a result, requires that all testing labs and CBs operate under a single set of rules and operational procedures; undergo the same qualification process to join IECEE (IEC System for Conformity Testing and Certification of Electrotechnical Equipment and Components), which includes a peer assessment as part of the certification process; use a common test report and certificate format, thus also maintaining the CB brand; and be re-assessed every three years.
The incentives for implementing the CB scheme include the removal of costly duplication of testing/certification at the local and national levels and, as a result, the associated delays to accessing or delivering new products to the market.
I have (and I am sure that many of you have) experienced not being able to purchase a product here in Canada that was available in the U.S. because it did not have the necessary approvals. I also know from my time at MTL that obtaining these approvals can be costly and take up to six months of a 12- to 18-month development cycle. So having portability of assessment results and certificates across multiple countries and preferably a single global approval will help immensely, especially as more and more projects become truly international in scope and delivery.
Of course, ensuring the successful operation of the scheme requires that national standards are reasonably harmonized with the corresponding IEC standards, which is often the difficult part. But it is possible — just look at the various free trade agreements and trade zones.
The initial starting point for the INDAT scheme will be the development of the following suite of standards related to industrial equipment:
• IEC 61010-2-201: Control systems, including PLCs, distributed control systems and process automation controllers. The completed documents will specify the complete safety requirements for control equipment, including the controllers, I/O devices and HMIs. Safety terms of general use are defined in IEC 61010-1, with more specific terms defined in each part. This part incorporates the safety-related requirements of programmable controllers. Annex DD provides a cross-reference between clauses of this standard and those of IEC 61010-1 or IEC 61131-2:2007.
• IEC 61010-2-20a: Standalone power supplies
• IEC 61010-2-20b: Actuators where movement is contained, such as rotational, linear valves
• IEC 61010-2-20c: Actuators where movement is not contained, such as rotational, linear slides and tables
• IEC 61010-2-20d: Human machine interface
As can be inferred from the description of IEC 61010-2-201, the standard suite will include Automation System Functional Safety Standards:
• IEC 61508: Functional safety of electrical/electronic/programmable electronic safety-related systems, which refers to generic electrical control systems
• IEC 61511: Functional safety – Safety-instrumented systems for the process industry sector
• IEC 62061: Safety of machinery – Functional safety of safety-related electrical, electronic and programmable electronic control systems
• ISO 13849-1:2006: Safety of machinery – Safety-related parts of control systems – Part 1: General principles for design
The plan is that once the ISA99 standard is accepted as an IEC document, the INDAT will also include automation system security standards, presently known as IECSecure.
Because the majority of large control and automation equipment suppliers who support the development of IEC, ISO and national standards fully support this initiative and have seen the positive impact of the CB scheme in other industries, it is expected that INDAT will be de facto accepted in the global market by regulators, retailers, buyers and vendors.
The good news is that for most of us on the consumer side of the purchasing equation, we should not see much change in the electrical approvals of our equipment, other than just as we are becoming accustomed to seeing FMC and ULC as alternatives to CSA, additional certifying organizations from outside of Canada will be accepted as well, especially if we sign the European Free Trade Agreement.
Though many of us take standards for granted, they have a large impact on our work. Our competition in Europe recognizes this. If you want to participate in the Canadian contribution to the development of international standards, such as those developed by IEC and ISO, let me know and I will put you in touch with the right people.
“IEC 61010-2-201 ed1.0” http://webstore.iec.ch/webstore/webstore.nsf/Artnum_PK/47585, 2013-09-20
This column originally appeared in the November/December 2013 issue of Manufacturing AUTOMATION.