The principle of the glow wire tester

The glow wire tester is suitable for the fire hazard test of electrical and electronic products, household appliances and their materials, and simulates the thermal stress caused by heat sources or ignition sources such as hot components or overload resistors in a short time.

Test principle: The glow wire tester simulates the parts of insulating materials or other solid combustible materials that are easy to spread flames inside the equipment, which may ignite due to the glowing wires or glowing components. Under certain conditions, such as fault current flowing through the wire, component overload, and poor contact, some components will reach a certain temperature and cause the nearby parts to ignite.

The working principle of the glow wire tester: The nickel-chromium wire (U-shaped glow wire head) of the specified material Φ4 mm is heated to the specified temperature (300 ℃ ～1000 ℃) for the test with high current, and then it is burned horizontally at the specified pressure (1.0N). Burn the test product for 30s, whether the test product and the bedding are ignited or lasted to determine the fire hazard of the finished electrical and electronic equipment; after the test is completed, record the burning time, ignition time (Ti), flame extinguishing time (Te), and combustible Sexual Index (GWFI).

Glow wire head: to measure the temperature of the glow wire, an armored thin-wire thermocouple with a nominal diameter of 0.5mm is used. The wires are nickel-chromium and nickel-aluminum (K type) wires, which are suitable for continuous operation at temperatures up to 960°C. The welding point is located in the sheath, and the thermocouple used to measure the temperature of the glow wire, the metal of the sheath can withstand a temperature of at least 1050℃.