1 Definition

The glow wire test is to test the stability of electronic and electrical products when they are working. The glow wire itself is actually a resistance wire ring with a fixed specification. During the test, it must be heated to a specified temperature with electricity, so that the top of the glow wire contacts the sample for a standard time, and then observe and measure its state. The test range depends on the specific test procedure.

2 Classification

2.1 GWFI——glow-wire flammability index

The highest test temperature of a test sample with a specified thickness in three consecutive tests shall meet one of the following conditions:

a) The flame or glow of the test sample is extinguished within 30 seconds after the glow wire is removed, and the wrapping tissue paper placed under the test sample does not ignite;

b) The test sample did not ignite.

2.2 GWIT——glow-wire ignition temperature

The temperature that is 25K higher than the highest temperature at the top of the glow wire (30K higher between 900°C and 960°C) than "three consecutive tests will not cause ignition of the test sample of specified thickness".

3 Severity level

3.1 The Glow Wire Flammability Index (GWFI)

Test temperature/℃:550/600/650/700/750/800/850/900/960

3.2 The glow wire ignition temperature (GWIT)

Test temperature/℃:500/550/600/650/700/750/800/850/900/960

4 Assessment of result

4.1 Evaluation of Glow Wire Flammability Index (GWFI) results

If the test sample does not ignite or meets the following two conditions, it is considered to have withstood the test

a) If the flame or glow wire of the test sample is extinguished within 30 s after the removal of the glow wire

b) The wrapping tissue did not ignite

If the above two or one of the two conditions are not met, select a lower test temperature and repeat the test with a new test sample.

If the above two conditions are met at the same time, select a higher test temperature and repeat the test with a new test sample.

The test shall be repeated at the highest test temperature at which the test sample satisfies conditions a) and b).

Therefore, it is necessary to determine that GWFI is the highest test temperature that meets the conditions a) and b) for three consecutive tests.

4.2 Evaluation of Glow Wire Ignition Temperature (GWIT) results

The ignition temperature of the test sample during the application of the glow wire shall be determined, and the test temperature that is 25K (30K between 900°C and 960°C) higher than the highest temperature at the top of the glow wire that did not cause the test sample to ignite in three consecutive tests shall be recorded as GWIT.

Shijiazhuang Qibo Chemical Co., Ltd. have 750°C, 850°C and 960°C glow wire special flame retardants.Compliant with common and stringent glow wire standards.