How do you do it ?

                  

How to test a LED bulb?

Before starting the  LED test we requieres a multimeter, thats is a1 special digital machine used to test the voltage of LED bulbs.

 First Step:   

                   Connecting the LED bulb to the multimeter.

            

The LED bulb has two terminals: the anode (positive) and the cathode (negative). Them you connect the black testing lead to the COM terminal on the multimeter and the red testing to the multimeter's terminal that ha the Omega sign. Be sure that black probe of the lead connect to the cathode and the red probe connects to the anode of the bulb. When you turn on the multimer display should show you "OL" or "OPEN".

Second Step:                     

                       Interpreting LED Test Results

If the multimeter display show you "OL" or "OPEN" you can be ure that connection is correctly, them you can start testing the LED bulb, first it is important to shield the bulb to see how it glows, if the bulb glows with a dim light the LED is with lower efficiency, but if the bulb glows with clarity and brightness the LED is with higher efficiency.