Glow Wire Test Apparatus> is designed to simulate parts of insulating material or other solid combustible materials that are prone to spread flames inside equipment that may ignite due to glow wires or glowing elements. 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 test device: heat the nickel-chromium wire (U-shaped glow wire head) with a specified material of Φ4 mm to the specified test temperature (300 ℃ ~ 1000 ℃) with a large current, and then burn it with a specified pressure (1.0N) level. Scald the test piece for 30 seconds to determine whether the test piece and bedding ignite or last for ignition time to determine the fire risk of the finished electrical and electronic equipment; after the test is completed, record the scorching time, ignition time (Ti), flame extinguishing time (Te), and flammability Sex Index (GWFI).
Glow wire head: To measure the temperature of the glow wire, use an armored filament thermocouple with a nominal diameter of 0.5mm. The wire is nickel-chromium and nickel-aluminum (K type) wire. It is suitable for continuous use at temperatures up to 960°C. In operation, their welding points are located in the armored sleeve. For thermocouples used to measure the temperature of the glow wire, the metal of the armored sleeve can withstand a temperature of at least 1050°C.
The glow wire test is a flame retardant performance test used in the electrical and electronic products industry to measure the stability of electronic products during operation. The glow wire test is a physical experiment with the purpose of testing the stability of electronic and electrical products during operation. The glow wire itself is actually a resistance wire ring with fixed specifications. During the test, it must be heated to a specified temperature by electricity, so that the top of the glow wire contacts the sample for the standard required time, and then its state is observed and measured. The test range depends on the specific test procedure.
Glow wire test method:>
The glow wire standard for household appliances is specified in IEC 60335-1, and the latest version is its Edition 5.0 2010-05. However, the specific glow wire test method is mainly reflected in specifications such as IEC 60695-2-10.
The glow wire test is performed by heating the element to a predetermined temperature. The heating element is called a glow wire. Figure 3 is an example of a heating element used in a glow wire test. The sample to be tested is held in place with tissue paper placed directly underneath the sample. After reaching the predetermined temperature, press the glow wire against the sample with a force of 1N for 30 seconds. If combustion occurs within 30 seconds, record the duration, flame height, and whether material drippings ignite the tissue paper.
Whether it is in the end product orGlow wire tests can be performed on raw material samples. The terms defining compliance are slightly different in the two cases.
GWT is short for Glow Wire Test (IEC 60695-2-11). GWT is used when performing glow wire testing on end products. The result of the test is either pass or fail at a given temperature. If the sample does not ignite or automatically extinguishes within 30 seconds after removing the heating element, if dripping occurs and the dripping does not ignite the tissue paper, it will be passed.
GWFI stands for Glow Wire Flammability Index (IEC 60695-2-12). It is a property related to the raw material used in the final product. This property is determined by conducting a glow wire test on a sample of raw material of a given thickness. GWFI is the highest temperature at which the glow wire does not ignite or automatically extinguishes within 30 seconds after the heating element is removed.
GWIT stands for Glow Wire Ignition Temperature (IEC 60695-2-13). It is a property related to the raw material used in the final product. This property is determined by performing a glow-wire test on a sample of the raw material of a given thickness. GWIT is the lowest temperature at which the material ignites and burns for more than 5 seconds when the heating element is in contact with the sample.
Experimental requirements for the ignition temperature test of insulating materials:>
In addition to the provisions of Chapter 8 of IOS 5169.10-2006, unless otherwise specified, the test sample shall be installed so that the top of the glow wire is applied to the surface portion of the test sample that may be subject to thermal stress during normal use. The glow wire should be kept as horizontal as possible. When testing more than one point on the same test sample, care should be taken that the degradation caused by the previous test cannot affect the results of subsequent tests.
When there is no detailed specification of the area where the equipment is subject to thermal stress during normal use, the top of the glow wire should be applied at the thinnest point of the test sample, and preferably not less than 15 mm from the upper edge of the test sample. During the test, the test sample is fixed on the experimental device, but no additional mechanical stress should be transmitted to the test sample.
Rating of test results:>
Unless otherwise specified in the relevant specifications, if the test sample does not burn or glow, or all of the following conditions are met, it is considered to have passed the glow wire test:
a) If the flame or glow of the test sample is extinguished within 30s after the glow wire is removed, that is testa+ 30s; .
b) When using the specified underlayment of wrapping tissue paper, the tissue paper shall not ignite.
ZRS-3H glow wire tester according to IEC60695-2-1, IEC60695-2-10,IEC60695-2-11, IEC60695-2-12, IEC60695-2-13 (IOS5169.10, IOS5169.11, IOS5169.12, IOS5169.13),