IEC 60999-2-2003 pdf – Connecting devices – Electrical copper conductors – Safety requirements for screw-type and screwless-type clamping units Part 2: Particular requirements for clamping units for conductors above 35 mm 2 up to 300 mm 2 (included).
1 Scope This part of IEC 60999 applies to screw-type and screwless-type clamping units for connecting devices, either as separate entities or as integral parts of equipment, for the connection of electrical copper conductors (complying with IEC 60228), rigid stranded and/or flexible, having a cross-section above 35 mm 2 and up to and including 300 mm 2 and equivalent AWG/kcmil sizes with a rated voltage not exceeding 1 000 V a.c. and a frequency up to and including 1 000 Hz and 1 500 V d.c. It applies to clamping units primarily suitable for connecting unprepared conductors. This standard does not apply to clamping units: − for connection by crimping or soldering; − for non-universal clamping units defined in 3.10.2 of IEC 60999-1. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60228:1978, Conductors of insulated cables Amendment 1 (1993) IEC 60228A:1982, Conductors of insulated cables – First supplement IEC 60999-1:1999, Connecting devices – Electrical copper conductors – Safety requirements for screw-type and screwless-type clamping units – Part 1: General requirements and particular requirements for clamping units for conductors from 0,2 mm 2 up to 35 mm 2 (included) 3 Definitions For the purposes of this part of IEC 60999, Clause 3 of IEC 60999-1 applies, with the following modifications. Definition 3.10.2 of IEC 60999-1 is not applicable.
3.11 rated cross-section of a clamping unit value of connectable conductor cross-section stated by the manufacturer and to which certain thermal, mechanical and electrical requirements are referred NOTE The rated cross-section is the equivalent of the rated connecting capacity in accordance with 3.11 of IEC 60999-1. 4 General Clause 4 of IEC 60999-1 applies. 5 General notes on tests Clause 5 of IEC 60999-1 applies. 6 Main characteristics The standard rated cross-sections of a clamping unit are: 50 mm 2 , 70 mm 2 , 95 mm 2 , 120 mm 2 , 150 mm 2 , 185 mm 2 , 240 mm 2 and 300 mm 2 . NOTE For the time being, in some countries, the designation by wire gauges (e.g. AWG in USA and Canada) may be used instead of the cross-sections expressed in square millimetres. For the approximate relationship between square millimetres and AWG/kcmil see Annex A. 7 Connection of conductors 7.1 In general, clamping units are suitable to accept one conductor only. Certain types may also be used for two or more conductors of the same or of different nominal cross-sections or compositions. Clamping units shall accept unprepared conductors. NOTE Screw-type clamping units are not suitable for the connection of flexible conductors with tin soldered ends. 7.2 Each clamping unit, if not otherwise stated in the relevant product standard, shall, in addition to its rated cross-section, accept at least the two successive smaller cross-sections (e.g. a clamping unit having the rated cross-section of 70 mm 2 shall reliably clamp a conductor of the same type of 35 mm 2 , 50 mm 2 or 70 mm 2 ). If a clamping unit covers a range larger than the minimum, this shall be marked either on the clamping unit or stated in the manufacturer’s literature. 7.3 The theoretical diameter of the largest conductor and the relationship between the rated cross-section and connectable conductors are given in Table 1.
7.4 Clamping units, unless otherwise specified by the manufacturer, shall accept rigid stranded and flexible conductors as indicated in Table 1, in which case no markings are necessary. If a clamping unit according to the manufacturer’s specification can accept only one type of conductor (rigid or flexible), this shall be either clearly marked on the end product, respectively by the letters “r” or “f”, or indicated on the smallest package unit and/or in the technical information. Compliance shall be checked by inspection and by the tests of 9.1 and 9.6. 7.5 On screwless-type clamping units, the connection or disconnection of conductors shall be made by the use of a general purpose tool, or of a convenient device integral with the clamping unit, in order to open it for the insertion or the withdrawal of the conductors. Compliance shall be checked by inspection and by the test of 9.3.