Street lamp should be taken to meet old led lamp bead recycling way

Street lamp grounding involves security in life, is a big shock hazard of electrical devices, especially in rainy day, people go in the water near the street lamp electric shock occurs when death is not a case. Although Wang Houyu teacher's building electric installation 500 q ( Hereinafter referred to as the '500 q'



street lamp grounding involves security in life, is a big shock hazard of electrical devices, especially in rainy day, people go in the water near the street lamp electric shock occurs when death is not a case.

although Wang Houyu 【 Wang Houyu, famous industrial and civil construction electrical technical experts, the international electrotechnical commission IEC/TCC4 under centralized committee and China national building electrical equipment standardization technical committee consultant. 】 The teacher's building electric installation 500 q ( Hereinafter referred to as the '500 q') In outdoor lighting device in this section has made the detailed introduction, but not everyone to understand while see, such as q: street light earthing system should take? Why do recommend using TT earthing system? Grounding resistance should be how old?

'500 q' divides into the street lamps garden lights, light, Light, generally refers to more than 15 meters steel conical light pole and high-power modular fixtures are composed of new type of lighting. 】 And traffic lighting lamps three kinds of lamps and lanterns are discussed. Three different use of the docking requirements are also different.

1, garden lamp

'500 q' explicitly pointed out that, the garden lamp should not adopt TN 【 English name: Text Normalization ( Structured text, text regularization) TN is the TTS ( 文本- - - - - - - Researched, text to speech) An important part of system, main function is to convert the number in the text, symbols, abbreviations, etc into language. 】 System, and should use TT system' TT way power system refers to the electrical equipment of the metal shell directly grounding protection system, known as the protective earthing system, also known as the TT system. 】 Or partial TT system.

why not TN system should be used? Many people think the TN system worse than TT system security, and even challenge the TT system, because the TT system short circuit occurs, the short circuit current solar street lamps for loop resistance than TN system, so the reaction time no TN system fast, there is nothing wrong with their analysis, but the TN system in the event of a relatively short circuit, neutral in before cut off power supply, power supply, PEN line 【 The PEN line is both protective earthing line ( PE line) And neutral electric function ( N line) The conductor. 】 Line, PE' PE line, English full name protecting the earthing, simplified Chinese name called [ Protect the conductor] , also is what we usually call [ Ground] PE line for green -, our country regulations Yellow double color line. 】 And the exposed conductive part of the electrical devices will bring dangerous breakdown voltage, people hit a electric shock may occur.

why the TN system in the building is very safe, and in the outdoor garden lights take TN system is unsafe, '500 q' points out: 'when a TN system for a building power supply, connect the power cord in phase earth fault, building outdoor parts using power tools will be electric shock and death, and within the building to use the same tools are safe. ”