LED street lights in a large number of applications in the present society, for the progress of lighting engineering has played a decisive role, especially the energy saving and low carbon two aspects of the LED street lamps have made important contributions to the society. Below we say that the 10 items should be paid attention to in the daily use process of the LED street lamp.
1, LED street lamp must be constant current
The characteristics of the lighting material of the LED street lamp determine that it is affected by the environment, such as the increase of temperature, then the current of the LED will increase, and the increase of the other voltage will increase the current of the LED. If the current exceeds the rated current for a long time, it will greatly shorten the service life of LED bulbs. LED constant current is to ensure that its current value remains unchanged when the environment factors such as temperature and voltage change.
Constant current precision of 2 and LED street lamp
In the market, the constant current accuracy of some power supply is poor, the error may reach + 8%, and the constant current error is too large. The general requirement is 3%. According to the 3% design. The production power should be fine tuned to achieve an error of + 3%.
The working voltage of 3, LED street lamp power supply
The recommended voltage for general LED is 3.0-3.5V. After testing, most of the work is in 3.2V, so the 3.2V formula is more reasonable. The total voltage =3.2*N in series of N lamps
4. How much is the working current of LED street lamp power?
For example, the rated working current of LED is 350 Ma, and some factories have been used to design 350 Ma at the beginning. In fact, the heating is very serious under this current. It is ideal to design 320 Ma by several contrast tests. Minimize the heat and make more electric energy visible light.
5. How wide is the series parallel connection and the wide voltage of the LED street lamp power board?
To make the power of LED street lamp work in a wide range of input voltage AC85-265V, the LED serial and parallel mode of the lamp board is very important. Try not to use a wide voltage, can be divided into AC220V, AC110V classification as far as possible, so as to ensure the reliability of power supply. Since the current power supply is generally a non isolated buck type constant current power supply, when the voltage is 110V, the output voltage should not exceed 70V, and the series number should not exceed 23 strings. When the input voltage is 220V, the output voltage can reach 156V. That is to say, the number of series is not more than 45 strings. The number of paralleling is not too much, otherwise the working current is too large and the power supply is very serious. There is also a wide voltage scheme. The APFC active power compensation is to raise the voltage to 400V by L6561/7527 and then to lower the voltage, which is equivalent to two switching power supplies. The scheme is used under certain conditions.
6, isolation / non isolation
General isolation power, such as 15W, is placed in the LED street lamp power supply. The transformer is very large and difficult to put in. Mainly depends on the spatial structure depending on the specific circumstances, isolation can only be 15W, less than 15W, and the price is very expensive. Therefore, the cost performance of isolation is not high, generally the non isolation of the majority of the mainstream, the volume can be done smaller, the minimum can be 8 millimeters high, in fact, non isolated security measures are done, there is no problem. Space allowed also can be used as an isolated power supply.
7, how can LED street lamp power match with the bead plate?
In fact, choosing the best serial connection mode is the same as the voltage and current on each LED, but the effect of power supply can give the best performance. The best way is to communicate with power suppliers and tailor them first. Or the power supply has been produced by itself.
Power efficiency of 8 and LED street lamps
The input power subtracts the output power value, which is particularly important. The greater the value, the lower the efficiency, which means that a large portion of the input power is converted to heat. If it is installed in the lamp, a very high temperature will be produced, and the heat emitted by a light efficiency ratio of our LED will superimpose higher. The life of all the electronic parts in our power supply will be shortened with the rise of the temperature. Therefore, the efficiency is the most fundamental factor in determining the life span of the power supply, and the efficiency can not be too low, otherwise the heat consumed on the power supply is too large. The non isolation efficiency is higher than the isolation type, generally more than 80%, but the efficiency is related to the matching of the lamp board.
9, LED street lamp light source heat dissipation
The main reason of the heat dissipation plan is that the LED street lamp bulbs can extend life greatly under the condition of no overheating. That is, the LED street lamp power beads are attached to the aluminum substrate, and the external area is maximally expanded.
10, LED street lamp power supply heat dissipation
The main factor of heat dissipation is the use of LED street lamp power beads under the condition of not overheating, which can greatly extend the life span. Generally, the aluminum alloy radiator is easier to dissipate heat. That is, the LED street lamp power beads are attached to the aluminum substrate, and the external area is maximally expanded.
The above ten major items for our detailed analysis of the LED street light points of attention, reasonable use will improve the life of the LED street lamp, reduce production costs, believe that no matter who will be very interested.