Common problems and solutions of outdoor lighting power supply

The quality of outdoor lighting power supply is the guarantee that there will be no abnormality in outdoor lighting within five years. The common problems and solutions of outdoor lighting power supply are analyzed as follows.

Question 1, the life of the power supply.
Because the electrolytic capacitor itself has the problem of electrolyte volatilization, it is often said that the life of the power supply is only determined by the electrolytic capacitor of the power supply. Is it really just like this?

  the answer is negative. Most of the time, capacitance is not the cause of the failure of outdoor lighting power supply. For example, the overall efficiency of Oulutong 200W outdoor LED power supply is 93%, and the temperature rise of the capacitor is 35 degrees. When the ambient temperature is 45 degrees or the shell temperature is 70 Under the condition of high temperature, the electrolytic capacitor with a life of 10,000 hours at 105 degrees can reach 80,000 hours of life under this application condition. This means that the life of the power supply in conventional applications can be as long as more than 10 years, which is longer than the life of the lamp itself Longer. (In order to achieve the longest service life of the power supply, it is recommended that the temperature rise of the lamp housing is less than 30 degrees.) In practical applications, the life of the power supply may be more affected by lightning strike failure, waterproof failure and other issues.

Question 2, Lightning strike failure problem
In the application of outdoor power supplies, especially in the suburbs where there are no other tall buildings, street lamps often fail due to lightning strikes. How to avoid the failure of induced lightning strikes, it is imperative to add external lightning protection modules or improve the lightning strike resistance of the power supply itself.
        The power supply is equipped with 4KV/4KV lightning protection as standard, and it can be extended to support 4KV/6KV lightning protection. The external 10KV lightning protection module can resist 10KV.
Due to the design margin, component batches, and production control, in order to control the lightning protection capability of the power supply, it is necessary to test lightning strikes for each batch for verification.

Question three, waterproof failure problem
In practical applications, the most stringent test for power supply waterproofing is when the power supply is working in hot weather and it suddenly rains, which has the highest failure rate.
According to the verification analysis, due to the sudden drop in temperature, the thermal expansion and contraction of the power supply itself lead to gaps in the metal joints, making it easier for water to enter.
At this time, it is necessary to rely on the glue itself to cover the surface of the components to prevent water from contacting the components. To solve this problem, the manufacturer adopts a multi-stage vacuum pumping method to eliminate glue bubbles to avoid waterproof failure.
Question 4, the problem of light flickering
We can often find that some lamps flicker on the road. What causes the lights to flicker?
1. The output constant current voltage range of the power supply does not cover the Vf change of the luminaire. Make sure that the luminaire is within the constant current voltage range of the power supply.
2. The problem of optocoupler CTR attenuation was not considered in the design of the power supply. After one or two years of operation, the constant current voltage of the power supply can not cover the Vf value of the lamp. The problem of CTR attenuation is considered in the design to ensure that the CTR attenuation reaches 30% after ten years The power supply is still working normally.
3. The input voltage is too low. Confirm that the input voltage is 220V during installation to ensure that there is no problem with the input wiring
4. The light flickers when the input voltage fluctuates. It is designed and verified before leaving the factory to ensure that when the power grid fluctuates 90-310V, the light will not flicker.
5. Lights flicker when dimming. Verify during design and test during production to ensure 10%-100% dimming of the power supply and no flickering problems with lamps.