Compliance with North American standards

30Oct

posted by: Ian Harwood, Rockwell Automation

For panel builders looking to break new grounds and reach wider markets, North America is a perfect fit, but there are considerations you need to make and hurdles to jump before looking to export. It all comes down to the electrical standards that impact every stage of a machine’s life cycle. If you are building panels for North American end users, you will need a strong understanding of not only the codes and standards but the changes within the region.

With growing interest in North American standards and having had many conversations with control system manufacturers and OEM customers over several years, I wanted to take this opportunity to tackle some of the most frequently asked questions and the need-to-know information for global panel builders.

Which standards do I need to meet?

Unfortunately, there is no single answer to this question as it all comes down to what you are trying to achieve. With that said however, there are three standards you need to be aware of. Here’s a quick synopsis of what they mean and why you need to meet them:

1. UL508A – Standard for safety of industrial control panels
Applying to almost all standard control panels (including requirements to comply with number two – NFPA79). The key takeaway from this standard is that there is no exact European counterpart, EN/IEC61439-1 and EN/IEC60204-1 have similar requirements but there are differences. These include the different methodologies for calculating a system’s short-circuit current rating (SCCR). SCCR is the maximum short-circuit current a component or assembly can safely withstand for a specified time when protected by the selected overcurrent protective device.

2. NFPA70 – National Electrical Code
Published every three years, this is probably the most well-used electrical standard in the USA and provides guidance for installation of electrical equipment. It also covers safeguarding of personnel from electrical hazards and “incorporates by reference” IEC60364-1, the standard for installations and rural and residential environments.

3. NFPA79 – Electrical standard for industrial machinery
Finally, this North American standard has been undergoing changes to align it closer with the European counterpart, EN/IEC60204-1. It covers the machine’s control panel but also the environment it is deployed in, the electrical equipment of the machine and the wiring of input and output devices. Operator interface, warning signs, documentation and testing are also included.

Understanding these standards is the first stage in reaching the North American market with your compliant systems. Delving down further, those panel builders that can identify the differences that exist between North American standards and their European counterparts will be the most successful at developing a global offering.

Read the full article in the November issue of PBSI