Compared with traditional energy-saving lamps, LED lighting LT8A23-43-UR96-T4 lamps have higher luminous efficiency and more environmentally friendly features. LED driver is specific power supply that convert AC or DC into constant voltage or constant current for LED. The LED driver is one of the core components of LED lighting fixtures, and its performance and reliability directly determine the effectiveness and working time of LED lighting fixtures. In order to be better used in LED lighting fixtures, the LED power supply needs to be tested at the development or production stage, operators must use suitable test solution for each indicator of the LED power supply.

The introduction to LED driver power supply testing

　In order to further improve the performance indicators and ensure the excellent quality of the LED driver, the manufacturers usually need to go through a rigorous testing process, which includes a wide range of testing items such as input testing, output testing, protection testing, safety testing, environmental testing and EMC testing,etc. Here is a brief introduction to several key test items for LED driver.

1. Energy Efficiency

　High efficiency LED is an energy saving product, so the efficiency of the LED driver should be high. The efficiency of LED power supply is more important for lamps with internal power supply. The luminous efficiency of LED will decrease with the increase of LED temperature, so the heat dissipation of LED is very important. The high efficiency of the driver means that it consumes less power and generates less heat in the luminaire, thus reducing the temperature of the luminaire

2.Power Factor

Power factor is the power grid requirements for the load. With increasing demands on the quality of electricity supply, customers are increasingly concerned about the quality and Harmonics problems by electricity-using equipment. The Technical Specification for Energy Efficiency Certification of AC Electronic Control Devices for LED Modules stipulates energy efficiency limits for LED control devices, with a minimum line power factor of 0.7　　 

3. Output Ripple

　Ripple is the AC voltage added to the DC output voltage, and is also an important measurement parameter in the LED power supply test. The ripple current is higher, it will affect the LED performance, and even to seriously reduce the life of the LED.

4.Input Inrush Current

　LED power supply to have the ability to suppress inrush current to protect the LED from damage. Input inrush current is generally at cold start, when the AC voltage is at the peak(90 °or 270 °) , the inrush current is maximum. The important components of the LED power supply, such as input fuses, rectifiers etc, its rating is generally higher than the input inrush current value.

5.Input Power Abnormal Test

　The main purpose of the input power anomaly simulation for LED  power supply is to assess whether the LED driver can meet the requirements of the EMC test for the voltage immunity test section. This part can be referred to IEC 61000-4-11: Immunity tests for voltage transients, short interruptions and voltage variations.

    In order to accurately evaluate the LED driver performance indicators and verify that each test item meets the technical requirements, a suitable test solution for LED driver needs to be selected.

Test scheme for LED power supply

 Test items of LED power supply include a series of parameters such as AC input range, power efficiency, power factor, ripple and noise, start and hold time, rise time, overload protection, overvoltage protection, electromagnetic compatibility and other performance indicators of LED driver. LED driver belongs to switching converter, so energy efficiency testing requires accurate measurements of the power and noise of distorted waveforms need to be accurately measured during energy efficiency testing, and the measuring instrument needs to have sufficient bandwidth to avoid measurement errors caused by filtering out high-frequency current components.

The standby power consumption of LED power supply should not be over 1W, and the standby test power consumption needs to measure mA-level current, which requires high-precision measurement capability for small signal current. Testing power needs to be able to provide a stable power and can simulate power supply abnormalities, such as frequency or voltage changes, and has a perfect protection function to meet the test requirements. 

According to the test items and requirements, a typical LED test program can be built.

Power test: AC inverter power supply PWR2000W

Measurement instrument: PA series power analyzer / power meter

LED load simulator　

The LED power supply test system is built with AC inverter power PWR2000W, PA series power analyzer or power meter and load simulator, which can meet the test requirements for each technical index of the LED power supply. For example, PA310 single-phase power meter input bandwidth up to 300kHz, basic power accuracy is 0.10%, the lowest current level is 5mA, which can fully meet the LED driver standby power consumption, energy efficiency and other parameters of the test requirements.

　PWR2000W has a highly stable output, the highest output frequency can be up to 1000Hz, support power supply abnormal simulation, output phase can be set to meet the requirement of LED power supply.　

　In addition, the AC inverter power PWR2000W has the functions of simulation output and sequence output by providing lines, which enables flexible simulation of various abnormal waveforms. The PWR Controller provides a test interface that meets the requirements of IEC 61000-4-11 and other standards, making it easier to perform power immunity tests on the inport of LED power supply