Tests on Electric Cables under Fire Conditions — Part 2: Test on a Single Small Vertical Insulated Copper Wire or Cable
1 Scope
This standard specifies a method of testing a small insulated wire under_ fire conditions when the method specified in GB/T 18380.1 is not suitable because some small conductors may melt during the application of the flame. The range of application. recommended is for solid copper conductors from 0.4 mm to 0.8 mm diameter and for stranded conductors from 0.1 mm2 to 0.5 mm2. cross-section. This standard includes the requirement for compliance.
Note: The use of insulated wire which complies with this standard is not sufficient to prevent flame propagation under all conditions of installation. When the risk of propagation is high, such as with long. vertical runs of bunches of wires, it cannot be assumed that because a sample complies with this standard the bunch will behave in a similar manner.
2 Performance Requirement
The test is intended for type approval testing or may be referred to in cable standards.
One sample of insulated wire or cable, after having. been tested in accordance with Clauses 6, 7 and 8, shall comply with the following requirement: After all burning has ceased, the surface of the sample shall be wiped clean and the charred portion shall not have reached within 50 mm of the lower edge of the top clamp.
3 Test Equipment
a) Propane burner complying with the requirements of Figure 1. It is allowable to fit an adaptor to burners not exactly complying with the figure in order to obtain the 8 mm bore shown.
b) Propane bottle with pressure device and pressure gauge.
c) Metal screen (1200 ± 25) mm high; (300 ± 25) mm wide and (450 ± 25) mm deep, with open front and closed top and bottom (see Figure 3).
d) Stop watch.
e) Electrically heated oven.
4 Sample
1 Scope
2 Performance Requirement
3 Test Equipment
4 Sample
5 Conditioning Before Test
6 Test Conditions
7 Source of Heat
8 Test Procedure
