Light-emitting diodes (LEDs) have become so prominent in so short a time that new standards and specifications are emerging faster than most engineers can gain familiarity with them. Prime among those are standards involving overcurrent and overvoltage protection from such organizations as the International Electrotechnical Commission (IEC), the Institute of Electrical and Electronics Engineers (IEEE), Underwriters Laboratories (UL), and the US Department of Energy's Municipal Solid State Street Lighting Consortium (MSSSLC), among others.
Experts say that most designers have a rudimentary understanding of the technical protection requirements for LED-based systems, but often need to be schooled on the details.
"Engineers know surge immunity," Usha Patel, director of the Latin American sales and segment marketing for Littelfuse Inc., told Design News. "They know they have to protect against lightning. They know they have to protect against inductive spikes. But there are areas where they still need to be educated."
The need to know involves many factors. Without protection, overvoltages and inductive spikes can damage sensitive electronics. And lack of understanding can cost money up front.
Patel, who has been involved with a DOE task force and other organizations on the creation of the specifications, suggests engineers familiarize themselves with the following standards:
Overcurrent protection for LED bulbs.UL 8750 addresses protection against the risk of shock and fire.
Overcurrent protection for LED luminaires. Key standards addressing the issue of overcurrent at the luminaire include UL 1598 and UL 1993, as well as UL 1310 and UL 8750.
Overvoltage protection for LED bulbs. Energy Star standards based on IEEE C62.41.2-2002 deal directly with surge suppression at LED bulbs. Outside the US, IEC61000-4-5 is the surge immunity specification for LED lighting.
Overvoltage protection for LED luminaires. DOE standards based on IEEE C62.41.2-2002 deal with surge immunity requirements for outdoor LED lighting.
There are other certification companies out there, cheaper ones. So, for those who could care less about UL standards, how do their LED regulations fair? For those people/companies, LEDs are a non-regulated business. I worked for a company making a LED system for a hybrid car. I worked on the signaling system. Based on the job's requirements and client requests, the power system would get extremely hot. I didn't like it, they didn't care, no regulations guided anyone. There needs to be a free and open regulation for such products.
Once a non-profit testing company becomes a required standard, it's a racket.
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