How to judge the quality of light source

The method is as follows: (When the appearance and brightness are the same) use a multimeter to measure the resistance of the light source. The smaller the resistance, the greater the light decay and the shorter the service life; the larger the resistance, the smaller the light decay and the longer the service life.

1. Identify the piranha module: The resistance of the white light and red light of the piranha module is generally 150 ohms. After testing the brightness, the customer can use a multimeter to test the resistance of the module. If the brightness is fine and the resistance is greater than or equal to 150 ohms, this piranha module is a module that can be used with confidence. (Users with conditions can test the current of the module. The white light is generally less than 20 mA and the red light is less than 40 mA) 2. Identify the patch module: White light patch modules are increasingly recognized by customers because of their low light decay. White light patches on the market are roughly divided into super bright and high bright. The resistance of super bright is about 90-100 ohms (current 30 mA) and the resistance of high bright is about 120-150 ohms (current 20 mA). If the two patch modules have the same resistance, the one with the highest brightness is the best.

3. Identify waterproof light strings: The main problem with light strings is the waterproofness. It is recommended that customers soak the light strings in salt water and light them for more than 100 hours to test the waterproof performance. The current of a 5V single-color light string generally does not exceed 20 mA. Light strings are prone to dead lights when plugged in (the reason is that the resistor wire is broken). Light strings using circuit boards and chip resistors are less likely to have problems.

4. To identify full-color light strings, use the controller to transform the light strings into white light to test the consistency and brightness of the white light of the light strings. The test method for waterproofing is the same as that for monochrome. Grayscale levels are generally divided into 32 levels and 256 levels. The 256-level grayscale has more vivid colors and better realistic effects. Please ask the customer about the grayscale level when purchasing full-color light strings.

The chip has a rated current value (20 mA for white light and no more than 40 mA for red light). When the current is greater than the rated value, the life of the chip becomes shorter and the brightness decays exponentially. If an LED product increases the brightness by increasing the current, such high brightness is unsustainable. The light decay can reach more than 50% or even higher within 3 months (actual test results). Due to the different chip sizes, the cost of LED products varies greatly. The service life of LED modules used within the rated power is more than 5 years. If it is overloaded, the life span is less than one year. In order for your company to prosper in the advertising industry, I hope you can choose LED products carefully.