Choosing LED lights to "look around"
As LED lights become more and more popular, the dazzling styles on the market make consumers have no idea where to start, so how to choose high-quality LED lights? Wang Linkang, secretary general of the Municipal Lighting Association, told reporters, "LED lamp products are uneven, and consumers can choose through visual identification and simple testing." ”
The first step is to look at the outer packaging of the LED lights. The state has requirements for the outer packaging of LED lights, and the rated voltage, voltage range, rated power, and rated frequency must be marked. The packaging and printing quality of high-quality LED light products is good, the handwriting is clear, and it is not easy to be wiped off with a damp cloth, while the inferior products are poorly printed and the font is blurred, and some products do not even have the manufacturer's logo and do not have relevant certification marks.
The second step is to look at the LED tubes. Put multiple LED lights of the same product together to watch, high-quality manufacturers generally have good consistency, and there will be no uneven pipe surface. There is a slope between the interface of the high-quality LED lamp and the spiral mouth, which is convenient for installation and prevents the installer from being electrocuted, while some of the poor-quality LED lamp interfaces are rounded, which has potential safety hazards. Pull it slightly hard at the screw buckle, if the interface is loose, it means that there is a quality problem and should not be purchased.
The third step is to probe the temperature. Put the LED light on the electric socket to work for a few minutes, generally the temperature of the LED light rises slowly, touch the temperature with your hand is lower, if the temperature is higher, it will affect the life of the LED light, do not buy.
The fourth step is the interference test. When the LED light is working, you can turn on the radio and put it near the LED light, the lower the noise emitted by the radio, the better the quality of the LED light.
Test Preparation
Measure 3 types of lights with the largest light measuring instrument in the city
Which of the three common bulbs is more energy-intensive? The reporter bought 3 common bulbs on the market for comparative experiments.
The price of these three bulbs purchased by the reporter ranged from 3 yuan to 50 yuan, of which the rated power of the incandescent lamp was 100 watts; The rated power of energy-saving lamps is 20 watts, which is equivalent to the brightness of 100 watts incandescent lamps; The LED lamp is rated at 9 watts, and the corresponding incandescent lamp has a brightness of 100 watts.
The test instrument used this time is a steel photometric integrating sphere with a diameter of 3 meters. According to the staff of Saibao, the steel photometric integrating sphere is a hollow sphere for photometry, and its inner surface is coated with diffuse white paint, and the illumination in any direction in the sphere is equal. In the sphere, there are various photosensitive instruments and current and voltage measuring instruments, which can test the brightness, luminous flux and color temperature of the light source in the sphere. The 3M photometric integrating sphere in the Saibao laboratory is the largest photometering instrument in our city.
Test Result (1)
LED lights are energy-saving and long-lasting, and the most cost-effective
In the sphere of the 3M photometric integrating sphere, the staff connected the incandescent lamp to a lamp holder with a voltage of 220 volts, turned off the sphere, waited for 5 minutes, and measured the current to measure the actual power of the bulb. After testing, it was found that the current of the incandescent lamp was 0.412 amps, and the measured power was 92.56 watts.
Similarly, if you connect the energy-saving lamp to a 220-volt lampholder, you need to wait for the energy-saving lamp to stabilize before testing because the energy-saving lamp has a 10-minute light stabilization time. After testing, it is found that the current of the energy-saving lamp is 0.1365 amps, and the measured power is 18.65 watts.
The LED lamp was connected to the lamp base, the sphere was closed, and the current of the LED lamp was measured to be 0.04579 amps, and the measured power was 9.337 watts.
Judging from the above data, the measured power of incandescent lamps is much higher than the power of other lamps, which shows that it consumes the highest power.
If you look at the selling price, the market price of a 9-watt LED lamp is 50 yuan, while the incandescent lamp is only 3 yuan, and the energy-saving lamp needs 15 yuan, and the purchase of an LED lamp is equivalent to the purchase of 16 incandescent lamps and 3 energy-saving lamps.
The staff told reporters that although the price of LED lamps is expensive, the life of LED lamps is generally more than 20,000 hours in terms of power consumption and bulb service life, while the life of incandescent lamps is generally only 1,000 hours, and the life of energy-saving lamps is generally more than 6,000 hours. In terms of power consumption, based on 1000 hours of continuous work, incandescent lamps need to consume 92.56 kWh, energy-saving lamps are 18.65 kWh, and LED lamps are only 9.337 kWh.
Based on the residential electricity cost of 0.5 yuan, 1000 hours of use, incandescent lamps need 46.28 yuan, energy-saving lamps need 9.325 yuan, and LED lights only need 4.67 yuan. In this way, it seems that the use of LED lights is the most cost-effective.
Test Results (2)
LED lights are the brightest, incandescent lamps are soft, and energy-saving lamps are dazzling
In the sphere, the staff connected 3 experimental bulbs to the lamp holder with a voltage of 220 volts, because the incandescent lamp and the energy-saving lamp have a light stabilization time, the 10-minute stabilization time of the energy-saving lamp shall prevail, wait for 10 minutes, the reporter used the same sensitivity, aperture and shutter rate exposure combination to take a set of photos of the three lamps, to observe the reflection degree of the sphere under different bulbs.
As you can see from the photos, although the LED light is only 9 watts, it has the highest brightness. The incandescent light is slightly weaker and the light color is yellow, but the overall sensory light appearance is soft. Energy-saving lamps are brighter than incandescent lamps, darker than LED lights, and the color is whiter, which is a bit dazzling when looking directly. This can also be seen from the color temperature data, the color temperature of incandescent lamps is 2665K, which is a warm color; The color temperature of energy-saving lamps and LED lamps is about 6000K, which is a cool color temperature.
Why is a 9-watt LED lamp brighter than a 20-watt energy-saving lamp and a 100-watt incandescent lamp? The staff told reporters that the conversion rate of LED lights is higher than that of the other two lights, and only a little bit of electricity is needed to emit bright light.
In the same way, incandescent lamps and energy-saving lamps have a relatively low conversion rate, and the electricity is converted into heat energy in addition to light energy, which is consumed. After 10 minutes of use of the three lamps, the reporter used his hands to check the temperature, and the temperature of the incandescent lamp was obviously too high to be directly touched by hand; Although the energy-saving lamp is also hot, it is not hot, while the LED lamp is only slightly warm when it is close to the lamp port.
It can also be seen from the data measured by the test integrating sphere that the luminous flux of LED lamps is 1021lm, while that of incandescent lamps is only 934.04lm.