Fire Testing
Circuit Integrity
3. Circuit (insulation) Integrity in accordance with EN 50200:2006
EN 50200:2006 defines method of test for resistance to fire of unprotected small cables (up to 20mm) for use
in emergency circuits. In the adapted chamber is mounted a cable sample with a length of 1200mm, to which
wire cores during the test a nominal value voltage is applied, creating thereby a closed circuit. During the test
the cable is subjected to actions of the fire at conventional temperature 842°C and mechanical stroke for a
specified period of time. The measured time of proper functioning of the cable corresponds to the so-called cable
fire resistance class PH, which is also mentioned in the standard PN-B-02851-1 - Fire resistance tests of
elements of buildings (Test method for thin wires with an outside diameter not greater than 20mm).
The test duration is expressed in minutes and is recorded in the following classification:
Test Cattegory
Flame exposure for 15 minutes PH 15
Flame exposure for 30 minutes PH 30
Flame exposure for 60 minutes PH 60
Flame exposure for 90 minutes PH 90
Flame exposure for 120 minutes PH 120
EN 50200 annex E also foresees the water stress (fire, mechanical shock & water spray), as previously
provided by BS 8434-1 standard. EN 50200 is similar to IEC 60331-2. Being different from BS 6387, EN 50200
test the same samples simultaneously stressed by the flame action, by the mechanical shock and by water
spray.