Street lights have a long lighting time and are installed outdoors, causing sun and rain, so the quality requirements of the lamps must pass. Otherwise, the damage to the lamps and lanterns will pose a threat to road safety. Therefore, whether enterprises, organizations or engineering companies in the procurement of street lights will need to be careful to identify, to avoid falling into the procurement trap.
Street light procurement requires attention to the following traps.
▶▶▶▶ Trap 1 Counterfeit chip, low-end chips
The core of LED lamps and lanterns is the chip, which directly determines the performance of the lamps and lanterns! However, certain unscrupulous manufacturers take advantage of the customer’s unprofessional, from the cost of the above considerations, the use of low-cost chips, so that customers with high unit prices to buy low-quality products resulting in direct economic losses, and LED lamps and lanterns cause serious quality risks.
▶▶▶▶ Trap 2 configuration false label, exaggerated configuration parameters
Solar street lights are also accompanied by a reduction in the price of profits, the fierce competition has also led to many solar street light manufacturers began to cut corners on false labeling of product parameters, light source wattage, solar panel wattage, battery capacity, and even solar street light pole with materials are in question. Of course, this is also the customer repeatedly than the price, the demand for low prices led to, but also with the practice of some manufacturers.
▶▶▶▶ Trap 3 heat dissipation design is poor, unreasonable configuration
Thermal design, LED chip junction temperature of the PN junction every 10 degrees, the life of semiconductor devices will be multiply decreasing. Due to the high brightness requirements of LED solar street lights, the use of a harsh environment, if the heat dissipation solution is not good, will quickly lead to LED aging, stability is reduced. In addition, unreasonable configuration often leads to the specific use of the situation that does not meet expectations.
▶▶▶▶ Trap 4 copper wire posing as gold wire and controller problems
Many LED manufacturers try to develop such as copper alloy, gold-covered silver alloy wire, silver alloy wire to replace the expensive gold wire. Although these alternatives are better than gold wire in some characteristics, in the chemical stability is much worse, such as silver wire and gold-clad silver alloy wire is susceptible to sulfur/chlorine / bromination corrosion, copper wire is easy to oxidation sulfide. For similar to absorbent breathable sponge encapsulated silica gel, these alternatives make the bonding wire more susceptible to chemical corrosion, the reliability of the light source is reduced, the use of a long time, LED lamp beads are more likely to break the line dead light.
Solar street light controller, if the controller is faulty, the process of testing and inspection, there will be “the whole light off”, “switch light is not allowed to time”, “partial damage”, “individual LED beads dead”. “Individual LED beads dead light”, “the whole light flickers false light” phenomenon.
Procurement staff in the procurement process need to pay attention to the following issues.
▼ Testing
Procurement, first of all, the light failure test report, which is a very important link. Bidding companies will provide different units of light failure test reports, some provide their own company self-test, there are also some third-party testing, which tests reports although the test results are good, the actual real light failure of the big difference, the reason we know, so how can the eye know the real product?
The test report is first of all the designated institution recognized by the Semiconductor Union. Such as Beijing Electric Light Source Quality Supervision and Inspection Center, Shanghai Electric Light Source Quality Supervision and Inspection Center, Semiconductor XIII, etc., from these units of the test report of the light decay has credibility, road lighting by using high power street lamps, heat generated by the large, through the light decay detection indicates two problems: light decay qualified, power supply pass. If a street lamp in the laboratory can not pass, on the road can also guarantee the quality?
▼ Street light structure
After the street light decay test, the structure is a big problem. This issue is rarely paid attention to in the industry, which is also one of the main reasons for the large light decay in the actual use of street lights.
As we all know, the national haze area is so large, it is not only harmful to the human body but also caused to the street light decay, especially in the northern region, sand and dust, haze, after a short period of outdoor use, the entire street light surface is covered with dust, its heat dissipation effect is greatly reduced. This is also one of the main culprits of LED street lights that are not known to the public.
According to this situation, the design of the lamps must be up and down through. Exponentially increase the heat dissipation area, because no street light management will be on time to clean up the radiator, in long-term use can only rely on rain flushing, the area increased also leaves enough for the reduction of effective heat dissipation area due to pollution.
▼ Heat dissipation
Street light failure has a barrel effect, there is a shortboard will not work, light failure has plagued us for so many years, the problem here is that you do a good job of lamps and lanterns heat sink can solve the light failure, not, we began to discuss the use of small power chip shell type package, high-power chips can not be said the chip power heat can not be dissipated, not so, COB package heat is more concentrated, through the aluminum bracket or copper Bracket can completely solve the problem of thermal conductivity.
But the light decay is more difficult to control, the reason is that the heat sink solution is not necessarily a good solution to the light source light decay problem, the light source package there is a big misunderstanding, COB light source silicone is too thick, should be the thinner the silicone package the better, to facilitate the chip light-emitting surface heat dissipation, which is the reason why COB light source light decay is not good control.