INCOMBUSTILITY APPARATUS - FOR INSULATION-AS PER IS 3144

INCOMBUSTILITY APPARATUS - FOR INSULATION-AS PER IS:3144

1. As per IS:3144, clause 16, fig. 3. Complete with heating furnace, observation chamber and tripod stand as per the specifications laid down.
2. Fire resisting characteristics of materials are very important to determine their suitability for use as insulating parts or insulating parts retaining live parts in position in electrical accessories and electrical appliances.
3. The EIE Fire Resistance Tester for insulating materials used in electrical accessories or appliances consists of a heating tube made from a cylindrical stainless steel pipe fixed vertically in the centre of an insulated rectangular enclosure, nichrome resistance wire encased in ceramic beads surrounding the heating tube to heat its interior, an observation chamber located below the heating tube for observing any burning debris falling from the material under test, a ceramic cone covering the top of the cylindrical chamber, a small tube giving a pilot flame with the help of LPG gas, and a digital temperature indicator to indicate the temperature inside the heating tube.
4. The observation chamber has a mica window and is located below the heating tube. The bottom of this chamber has a threaded cap with holes for air intake. The upper end of the heating tube is covered with a conical cover made of refractory material on which are fitted a metal tubing for pilot flame and a thermocouple for measuring temperature at the centre of heating tube at the level of the center of the test specimen.
5. The test specimen is supported on a wire mesh made of nichrome wire in such a manner that it is located centrally in the heating tube with its largest dimension vertical and its upper end located 20 mm below the pilot flame.
6. The enclosure of the heating tube is mounted on four legs and is fixed on a steel sheet panel, which has a main switch for providing electric supply to the heating element surrounding the heating tube, an electronic voltage regulator to control the voltage supplied to the heating coil, and a digital temperature indicator for indicating temperature inside the heating tube with the help of the thermocouple fitted on the conical cover.

  TECHNICAL DATA

1. Dimension of heating tube  :75 mm dia x 125 mm high
2. Open area of conical cover   :650 mm
3. Area of air intake holes    :65 mm
4. Dimensions of observation window :40 x 65 mm
5. Temperature range : upto 750°C

RELATED STANDARDS

1. IS 302 ‑ 1979: General and Safety Requirements for Household and Similar Electrical Appliances
2. IS 1293 ‑ 1988: Specification for Plugs and Socket Outlets of 250 Volts and Rated Current up to 16 Amperes
3. IS 3144 ‑ 1981: Methods of Test for Mineral Wool Thermal Insulation Material