NEMA ICS 4-2005

Applies to one-piece, or modular, or two-piece terminal blocks with screw-type or screwless-type clamping units intended for industrial use and fixed to a support or to a printed circuit board to provide electrical and mechanical connection for round, solid or stranded conductors. Terminal blocks are intended for use in circuits of rated insulation voltage not exceeding 1000 V ac at a frequency not greater than 60 Hz, or not exceeding 1500 V dc.