Tests on Electric Cables Under Fire Conditions - Part 3-21: Test for Vertical Flame Spread of Vertically-Mounted Bunched Wires or Cables - Category A F/R
|Publication Date:||1 October 2000|
|ICS Code (Cables):||29.060.20|
|ICS Code (Ignitability and burning behaviour of materials and products):||13.220.40|
|ICS Code (Electrical engineering in general):||29.020|
The series of International Standards covered by Parts 3-10, 3-21, 3-22, 3-23, 3-24 and 3-25 of IEC 60332 specifies methods of test for the assessment of vertical flame spread of vertically-mounted bunched wires or cables, electrical or optical, under defined conditions.
NOTE For the purpose of this standard the term "electric wire or cable" covers all insulated metallic conductor cables used for the conveyance of energy or signals.
The test is intended for type approval testing. The requirements for the selection of cables for testing are given in annex A. The flame spread is measured as the extent of damage of the cable sample. This procedure may be used to demonstrate the cable's ability to limit flame spread.
This part of IEC 60332 covers category A F/R and relates only to power cables of conductor cross-sectional area greater than 35 mm² installed on the test ladder in a spaced configuration on the front and rear to achieve a nominal total volume of non-metallic material of 7 l/m of test sample. The flame application time is 40 min. This method of mounting is intended for special cable designs used in particular installations when required in the cable specification. Category A F/R is not intended for general use.
A recommended performance requirement is given in annex B.