What is flicker?
Flicker is the discomfortableness to eye cause by the lights brightness changes .
Due to the sensitivity of the general electric equipment to voltage fluctuation is far lower than the incandescent lamp, so choose “flicker”, one subjective visual sense of incandescent lamp illumination fluctuations, as a measure of voltage fluctuation hazard evaluation index.
Flicker disturb degree is decided by two key indicators: the change of the power supply voltage amplitude and repetition frequency changes.
Where is flicker come from?
In daily life, when we open the air conditioning, high power washing machine such as high-power household appliances, or factory start the motor, the power equipment such as rolling mill, often arise the lights dimmed, suddenly short time internal energy will be back to normal.
Flicker caused by voltage fluctuation, usually a kick-off meeting for large load resulting in a decline in the short time of the voltage, and back to normal in a short time, when the voltage is reduced by 10%, 60 w incandescent lamp brightness will be reduced by 34%.
What is the harm of flicker?
Flicker reflects the voltage fluctuations, voltage fluctuations can cause the following problems:
1. The fluorescent lights and TV brightness changes when the voltage fluctuates, there is flicker when continuous wave voltage in a wide range.
2. the life expectancy of incandescent lamp shortened by 70% when the voltage is higher than 10%,, when the voltage is lower than the rating , a sharp drop in luminous efficiency;
3. Test for equipment that has a high output accuracy, when the input voltage fluctuation, the output precision will be affected.
4. When electric equipment power supply voltage is lower than the 10%, heating quantity will be reduced by more than 20%, the prolonged, warming is higher than the rating voltage will shorten the service life of heating element;
5. Voltage fluctuation will affect the efficiency and service life of the induction motor, such as the voltage is lower than 10%, the electromagnetic torque of the motor dropped to about 81% of the rated torque, which resulted in increased current, coil, fever, loss increase, lower efficiency and shorten service life.