The Theory of Glow Wire Tester with Glow Wire

I. Definition of Glow Wire Test
The Glow Wire Tester is used to test the stability of electronic appliances when working. The hot thread itself is actually a fixed-specification resistance wire loop. During the test, the hot thread needs to be heated to a predetermined temperature by electricity, so that the top of the hot thread can be contacted with the sample to meet the standard requirements, and then observe and measure its state. The range of the test depends on the specific test procedure. GB/T 5169 specifies the method of determining the combustibility index (GWFI) of hot thread on solid electrical insulation materials or other solid materials. The test results can be used to compare the performance of the above materials, i.e. the ability of the materials to extinguish the flame after removing the electrically heated hot thread and the ability not to produce combustion or hot particles underneath the test sample that will cause the underlayer packing silk paper to burn. This test method is not applicable for determining the combustibility of the whole equipment, because the structure size of the insulation system or combustible components and the arrangement and heat transfer of the adjacent metal or non-metallic components have a great influence on the combustibility of the used materials. In addition, this test method is also not applicable for determining the fire resistance performance and fire hazard of the equipment.

LISUN ZRS-3H Glow-wire Test Apparatus is according to IEC60695-2-1, IEC60695-2-10, IEC60695-2-11, IEC60695-2-12, IEC60695-2-13 (GB/T5169.10, GBT5169.11, GBT5169.12, GB/T5169.13) < Basic testing methods of Glow wire, basic testing methods of Glow wire device>, UL 746A, IEC829, DIN695 and VDE0471.

ZRS-3H Glow-wire Test Apparatus

The Glow Wire Tester is mainly used to simulate the parts of the insulation material or other solid combustible material in the equipment which can easily cause the flame to spread, the principle is to heat the prescribed material Φ4mm nickel-chromium wire (U-shaped hot wire head) with high current to the test temperature (300℃-1000℃), and burn the specimen level with the prescribed pressure (1.0N). Time for 30s, test specimens and pads whether combustion or sustained combustion time to determine the ignition hazard of electrical and electronic equipment finished products; record the burning time after the test, ignition time (Ti), flame extinction time (Te), combustibility index (GWFI).

II. Scope of application

The Glow Wire Tester is suitable for lighting equipment, low-voltage electrical appliances, household electrical appliances, machine tool electrical appliances, motors, electrical tools, electronic instruments, electrical and electronic instruments, information technology equipment, electrical connectors and laying parts. Such as electrical and electronic products and their components and components have research, production departments, but also for insulating materials, engineering plastics or other solid combustible materials industry. In view of the above description of the working principle and application scope of the hot wire, we also have a more in-depth understanding of the knowledge of the hot wire. In addition, there are two product models for the hot wire burning tester of LISUN: the conventional type ZRS-3H and the compact type ZRS-3HS. The glow wire tester of LISUN is fully in line with IEC60695-2-1, IEC60695-2-10~IEC60695-2-13 (GB/T5169.10-2006~GB/T5169.13-2006). This set of equipment is mainly used for fire resistance tests by quality supervision departments and related enterprises.

III. Requirement for Lamp Component Glow Wire Test
According to the standard requirement, the temperature of glow wire test required in each part of the lamp structure is different, specifically as follows:
1. To ensure the minimum level that parts are ignited and cause fire hazard, the temperature of hot wire test is 550 degrees;
2. For normal use of equipment, the temperature of glow wire test is 650 degrees;
3. Under strict conditions and with normal use of the equipment and fixed parts, the temperature of glow wire test is 750 degrees;
4. For the equipment with continuous load and unsupervised use, the temperature of glow wire test is 850 degrees;
5. Under strict conditions and with continuous load and unsupervised use, the equipment planned to be used in the vicinity of building power points, the temperature of glow wire test is 950 degrees.

IV. Glow Wire Test Pre-treatment
The important preparation step for the fire performance test of the material is pre-treatment. The sample will have different ignition performance, flame spread performance and self-extinguishing ability under different temperature and humidity conditions. Therefore, in order to enable comparison among the glow wire tests, the temperature and humidity and time of pre-treatment must be specified. The standard stipulates that the sample and the base cloth must be placed in an atmospheric environment with temperature of 15-35℃ and relative humidity of 45-75% for 24 hours before the test. The laboratory should be equipped with temperature and humidity meter. When the environmental temperature and humidity do not meet the requirements, the atmospheric environment should be adjusted through air control device.