Updated technical references for one-piece (modular) or two-piece industrial-use terminal blocks have been published by the National Electrical Manufacturers Association (NEMA).

Last published in 2010, ICS 4-2015 Application Guideline for Terminal Blocks updates technical references to IEC 60947-7 series and ANSI/UL standards.

The standard applies to terminal blocks with screw-type, screwless-type or insulation—displacement clamping units intended for industrial use, and that are fixed to a support or a printed circuit board to provide electrical and mechanical connection for round, solid or stranded conductors.

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