What are the requirements for the plug (also called the lamp holder) of the led fluorescent tube
LED fluorescent lamps are prone to problems in the three places where the lamp cap, screws, basic insulation and accessible metal parts contact. The lamp holder needs to meet the torque test specified in GB18774-2002 and the size requirements specified in GB2799-2001. Among them, the torque test specified in GB18774-2002 requires that both before and after the high temperature test be in compliance with the provisions of clause 2.3.1 of the standard, that is, when the torque test is applied, the rotation between the parts of the lamp cap should not exceed 6°. The high temperature condition applied by the lamp cap is (125±5)℃, and the heating time is (2000±50)h. If G13 lamp holder is used and the lamp power is greater than 40W, the high temperature condition is: (140±5)℃. High-temperature conditions and duration are more stringent for the assessment of LED fluorescent lamps with plastic materials in the lamp cap. Using plastic lamp caps with low heat resistance, after applying such a long period of high-temperature conditions, the plastic parts are likely to have softened. If a metal lamp holder is used, it is relatively easy to meet this test condition, but the connection between the metal lamp holder and the LED fluorescent lamp body, as well as the creepage distance and electrical clearance, should also be considered. The screws at the base of the LED fluorescent lamp mainly play the role of connection and fixation between the base and the lamp body. At present, the diameter of the screw at the base of the common LED fluorescent lamp is less than 3mm, and according to the regulations of GB 7000.1, this type of screw needs to be screwed into metal. The current common practice is to use an aluminum shell for LED fluorescent lamps, and this screw is directly screwed into the metal shell, which can also meet the requirements. However, a common problem caused by this is that after the screw is screwed into the metal shell, the screw and the live metal part of the lamp cap are too close, which easily leads to unqualified creepage distance and electrical clearance.
