UL 98-2016 pdf download – Enclosed and Dead-Front Switches.
5.1 0 CURRENT-LIMITING FUSE (AC) – a fuse that safely interrupts all available currents within its interrupting rating and, within its current-limiting range, limits the clearing time at rated voltage to an interval equal to or less than the first major or symmetrical current loop duration and limits peak let-through current to a value less than the peak current that would be possible with the fuse replaced by a solid conductor of the same impedance. 5.1 1 CURRENT-LIMITING FUSE RATING – a rating expressed in terms of three characteristics that measure the degree by which the fuse limits current. These are threshold ratio, maximum peak let-through current, and maximum clearing I 2 t. 5.1 2 CURRENT RATING – the designated maximum direct or alternating operating current in rms amperes at rated frequency for which the switch qualifies under specified test conditions. 5.1 3 DEADFRONT SWITCH – a switch that has all current-carrying parts enclosed when it is mounted in an enclosed panelboard, deadfront switchboard, or the like. 5.1 4 DETACHABLE PULLOUT – a type of pullout switch that is operated by physical removal and reinsertion of a detachable pullout member. 5.1 5 DIELECTRIC TESTS – tests made to determine the ability of insulating materials and spacings used to withstand specified overvoltages. 5.1 6 DOUBLE-THROW SWITCH – a switch by means of which a change in circuit connections can be obtained by operating the switch into either of two closed positions or into an open position. 5.1 7 DUMMY FUSE – a current-carrying part made of copper and having dimensions such that it will fit its fuse mounting means with the same conditions of pressure, contact, and cross-section area as are obtained on terminals of the fuse that it is intended to replace. A dummy fuse is not a protective device. 5.1 8 ELECTRICALLY TRIPPED SWITCH – a switch whose closing is performed manually, but whose contact opening may be performed by a release which is energized by a voltage source in addition to the manual operating means.
5.36 PLUG FUSE – fuse consisting of a current-responsive element inside a housing with coaxial terminals on one end, one terminal being a threaded metal ring or shell on the outside of the housing. 5.37 POLE OF A SWITCHING DEVICE – the portion of a switching device associated exclusively with one electrically separated conducting path of its main circuit and excluding those portions which provide a means for mounting and operating all poles together. 5.38 PRESSURE WIRE CONNECTOR – a reusable connector into which the conductor (wire) is secured by mechanical pressure applied by integral screw, cone, or other mechanical parts. 5.39 RATING – a designated limit of operating characteristics based on specified conditions of current, voltage, frequency, and such. 5.40 SERVICE EQUIPMENT – the necessary equipment, usually consisting of a circuit breaker or switch and fuses, and their accessories, located near the point of entrance of supply conductors to a building or other structure, or an otherwise defined area, and intended to constitute the main control and means of cutoff of the supply. 5.41 SHORT-CIRCUIT CURRENT RATING – the maximum available rms symmetrical ac current or maximum available dc current (which is marked on the switch) to which the (fused or unfused) switch is intended to be connected when protected by the specified overcurrent protective device or devices. 5.42 SINGLE-THROW SWITCH – a switch which has an open and a closed circuit position only. 5.43 SWITCH – a device, manually operated, unless otherwise designated, for opening and closing or for changing the connection of a circuit. 5.44 SWITCHING DEVICE – called ″single-pole″ if it has only one pole. If it has more than one pole, it is called ″multipole″ (two-pole, three-pole, and so on) provided the poles are coupled in such a manner as to operate together.