1. the arcing ceiling lamp wire connector exist within virtual connection and discharge light just open sound, light current is stable after the sound decreased or disappeared, there is a risk of fire, recommends open check is, redo the connector. Some poor quality lamps have no Terminal block and the power head cord, single unit family standard plastic copper wire twisted easily broken column press-fit or not.

2. the older inductive-type ballasts for use after a long period of organic changes, easier to "hum" sound, and may be accompanied by a high fever, it is recommended that replacement.

3. most of the fixtures with electronic ballasts. Through electronic rectifier high frequency inverter light lamp, differences in the quality of the internal components, welding, design defects, defects caused interference resonance may emit electricity shocks, it is recommended that replacement.