IEC 60331-3:2018 specifies the test method for cables which are required to maintain circuit integrity when tested in a metal enclosure and when subject to fire and mechanical shock under specified conditions. This document is applicable to cables of rated voltage not exceeding 600 V/1 000 V, including those of rated voltage below 80 V, metallic data and telecom cables and optical fibre cables. It is intended for use when testing cables not greater than 20 mm overall diameter. This document includes details for the specific point of failure, continuity checking arrangement, test sample, test procedure and test report relevant to electric power and control cables with rated voltage up to and including 600 V/1 000 V. Details for the specific point of failure, continuity checking arrangement, test sample, test procedure and test report relevant to metallic data and telecom cables and optical fibre cables are not given by IEC 60331-3. Although the scope is restricted to cables with rated voltage up to and including 0,6/1,0 kV, the procedure can be used, with the agreement of the manufacturer and the purchaser, for cables with rated voltage up to and including 1,8/3 (3,3) kV, provided that suitable fuses are used. It is not assumed that cables successfully assessed by this method, will also pass requirements for either IEC 60331-1 or IEC 60331-2. Testing to either of these two standards is to be carried out separately. Such additional performance can be recognised by the marking in accordance with IEC 60331-1:2018 Clause 11 or IEC 60331 2:2018 Clause 11. This second edition cancels and replaces the first edition published in 2009. It constitutes a technical revision. The significant technical changes with respect to the previous edition are as follows:
- extension of the scope to include metallic data and telecom cables and optical fibre cables, although details for the specific point of failure, continuity checking arrangement, test sample, test procedure and test report relevant to metallic data and telecom cables and optical fibre cables are not given by IEC 60331-3;
- improved description of the test environment;
- mandatory use of mass flow meter/controllers as the means of controlling accurately the input flow rates of fuel and air to the burner;
- improved description of the information to be included in the test report.