Laboratory Flame Retardant Test Apparatus For Electric Cables
As per IEEE Std. 383-1974
Covers a method to assess the ability of grouped electric power control and instrumentation cables via the vertical tray flame test to determine their relative ability to resist fire.
The fire test should demonstrate that the cable does not propagate fire even if its outer covering and insulation have been destroyed in the area of flame impingement.
Test should be conducted in a naturally ventilated room or enclosure free from excessive drafts and spurious air currents. The vertical tray configuration is recommended as the best arrangement to establish whether or not a cable could propagate a fire. The tray (ladder) is a vertical metal, ladder type, 3 inch deep, 12 inch wide, and 8 ft long. The ladder is bolted at the bottom to a length of horizontal tray for support.
The ribbon gas burner shall be mounted horizontally such that the flame impinges on the specimen midway between the ladder rungs, and so that the burner face is 3 inch behind and approximately 2 ft. above the bottom of the vertical ladder. The flame temperature should be approximately 1500 °F (815°C) when measured by a thermocouple located in the flame close to, but not touching the surface of the specimens (about 1/8 inch spacing). Under dynamic condition, if propane gas is used the pressure shall be --2.6 ± 0.3 cm of water at the supply side A to the Venture mixer. If commercial gas is used the pressure shall be – 0.9 ± 0.1 cm of water when measured at the supply side of the Venture mixer. For propane gas, the air pressure should be 4.3 ± 0.5 cm of water, measured at the air inlet B to the mixer.