Effects of LED Lamps on the Power-line Communications Channel

LED (Light Emitting Diode) lamps have recently come on to the market as energy efficient alternatives to incandescent light bulbs. Although energy effective, they inject conductive noise into the power-line system. This can have a detrimental effect on the power-line communications channel. This paper investigates these effects when LED lamps are seen as noise sources on the power line. It shows that there are two classes of LED lamps - depending on the noise generating electronics used as drivers for the light emitting diodes. Different driver electronics have different influences in different parts of the emission spectrum. It is shown that in the CENELEC band: (3kHz - 150kHz) the interference level from LED lamps is significantly below the allowed maximum PLC signal levels. In the band 150kHz - 30MHz however, PLC signals compete with Electromagnetic Compatibility (EMC) levels and the SNR can be equal to zero, but only if the lamps have active power electronic converters.