UL 1059:2001 pdf download Underwriters Laboratories Inc. Standard for Safety Terminal Blocks
1 Scope
1.1 These requirements cover assemblies of wiring terminals and supporting blocks intended to providefor the connection of wiring. Compliance with these requirements does not assure that the terminal blockis suitable for use as a component of an end product.
1.2 These requirements cover terminal blocks rated 1500 volts or less.
1.3 These requirements also cover protective conductor terminal blocks (PCTB) used to make theelectrical and mechanical connection between conductors or between conductors and a fixing supportsuch as a mounting rail. A PCTB is not required to be insulated.
1.4 These terminal blocks are intended to permanently support and insulate wire terminations and jointsfrom each other, and from the surface on which the terminal block is mounted, where the absence of suchsupport or insulation presents a risk of fire, electric shock, or injury to persons.
1.5 The acceptability of a terminal block in any particular application depends upon its suitability foicontinued use under the conditions that prevail in actual service. Accordingly, for a particular applicationa terminal block may be affected by the requirements for the equipment in which it is used, and it may benecessary to additionallv evaluate that terminal block for features or pertormance characteristics that arenot specified in this standard.
1.6 Terminal blocks employing types of connecting means not covered by this standard such as those inwhich conductors are secured to the terminals by means of a special tool can be evaluated under thisstandard but may require separate investigation
1.7 These requirements do not cover field installed power distribution blocks intended to distribute powerin a building to separate units such as apartments, separate heaters, and air conditioning units. Poweldistribution blocks are investigated to Subject 1953, Outline of lnvestigation for Power Distribution Blocks.
2 Glossary
2.1 For the purpose of this standard the following definitions apply
2.2 FACTORY WIRING – The connection of a wire in the end application under controlled conditionsusually at a manufacturer’s location.
2.2 revised September 13, 2004
2.3 FIELD WIRING – The connection of a wire, which is made in the field and that is subjected to therequirements for a terminal for field wiring as specified in this standard and the National Electrical CodeNFPA 70
2.3 revised September 13, 2004
2.4 INSULATION PIERCING OR DISPLACEMENT CONNECTOR – A connector for the connectionand possible disconnection of on conductor or the interconnection of two or more conductors, theconnection being made by piercing, boring through, cutting through, removing, displacing, or makingineffective in some other manner the insulation of the conductor or conductors without previousstripping.