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  • 4.2 Sample A 2 m length of cable shall be cut from the end of the cable and discarded in order to avoid end effects. The test sample lengths shall be cut from the adjoining cable. Five test samples of the length specified in the detail specification shall be cut from the cable. – For test samples of a nominal 1 m length, cut 1 050 mm ± 5 mm. – For test samples of a nominal length of 150 mm, cut 160 mm ± 5 mm. 4.3 Apparatus A horizontal surface where the test samples are placed that permit...
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  • 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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 60445, Basic and safety principles for man-machine interface, marking and identification – Identification of equipment terminals, conductor terminations and conductors 3 Terms and definitions No terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in standardization at the following addresses: • •...
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  • 4 Test apparatus General 4.1 The test apparatus consists of a climatic system, test enclosure, gas delivery system and means for measuring gas concentration, detailed in IEC 60068-2-60:2015, Annex B. Details of design and construction are optional but shall be such that the conditions specified for the method are fulfilled throughout the working volume and shall comply with the following requirements: water droplets or aerosols shall not be injected into the test enclosure; air and water used shall be sufficiently clean in order not to affect performance of the test; the test atmosphere shall flow through the enclosure in such...
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  • 5.2 Burner and test flame The burner shall conform to IEC 60695-11-4. The flame size and the gas flow rate will differ from that specified in IEC 60695-11-4 in order to obtain the heat flux necessary for the test. The test flame used for each test shall be kept unchanged throughout the test. The fuel gas shall be methane gas having a purity of 98 % or greater. 5.3 Heat flux meter The heat flux meter shall be of a water-cooled thermopile type (see ISO/TS 14934-4) which determines the incident heat flux, Q, applied to the test specimen. When incident...
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  • The temperatures in Table 3 are based on the intrinsic properties of the insulating materials. It is important to take into account other factors when using these values for the calculation of current ratings. For example, in normal operation, if a cable directly buried in the ground is operated under continuous load (100 % load factor) at the maximum conductor temperature shown in Table 3, the thermal resistivity of the soil surrounding the cable may, in the course of time, increase from its original value as a result of drying-out processes. As a consequence, the conductor temperature may greatly exceed...
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  • 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: • • IEC Electropedia: available at http://www.electropedia.org/ ISO Online browsing platform: available at http://www.iso.org/obp 3.1 long rod insulator suspension or tension insulator consisting of an approximately cylindrical insulating part provided with sheds and equipped at the ends with external metal fittings Note 1 to entry: The insulator is designed in such a manner that the shortest puncture path through solid insulating material is at least equal to half the arcing...
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  • 1 Scope This International Standard applies to string insulator units of the cap and pin type with insulating parts of ceramic material or glass, intended for AC overhead lines with a nominal voltage greater than 1 000 V and a frequency not greater than 100 Hz. It also applies to insulators of similar design used in substations. This document applies to string insulator units of the cap and pin type either with ball and socket couplings or with clevis and tongue couplings. This document applies to string insulator units for use on overhead lines in clean areas and polluted areas....
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  • 1 Scope This part of IEC 60286 applies to the tape packaging of components with axial leads for use in electronic equipment. In general, the tape is applied to the component leads. It covers requirements for taping techniques used with equipment for the preforming of leads, automatic handling, insertion and other operations, and includes only those dimensions which are essential to the taping of components intended for the above-mentioned purposes. 2 Normative references The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated...
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  • 5.2 Closed circuit voltage U cc (CCV), internal resistance and impedance Closed circuit voltage and internal resistance shall be measured according to 7.2. AC impedance should be measured with an LCR meter. Limit values shall be agreed between the manufacturer and the purchaser. 5.3 Capacity The capacity shall be agreed between the manufacturer and the purchaser on the basis of a continuous discharge test, according to 7.2.6. 5.4 Capacity retention The capacity retention is the ratio between the capacities under the given discharge conditions measured on fresh batteries and a sample of the same lot stored during 365 days at...
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  • 5.1.2 Resilient mounting The natural frequency of the support system and the machine under test shall be lower than a third of the frequency corresponding to the lowest rotational speed of the machine. The effective mass of the resilient support shall be not greater than one-tenth of that of the machine under test. 5.1.3 Rigid mounting The machines shall be rigidly mounted to a surface with dimensions adequate for the machine type (for example by foot or flange fixed in accordance with the manufacturer’s instructions). The machine shall not be subject to additional mounting stresses from incorrect shimming or fasteners....
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