Electronic Ballasts: Purposes and Features
Electronic ballasts regulate the electric current in fluorescent lights, ensuring efficient operation and preventing premature burnout. They deliver a steady, reliable light source, commonly used in offices, warehouses, schools, and hospitals.
Starting Methods
Ballasts start lamps and provide the proper voltage to establish an arc between the lamp's two electrodes. There are two types of starting methods.
Instant Start
The most cost-effective method, starts lamps almost instantly (under 0.1 seconds) with no flicker.
- Best suited for applications with minimal daily on/off cycles, these ballasts deliver a high starting voltage to ignite the lamps without preheating the electrodes.
- By eliminating electrode heating, instant-start ballasts save approximately 2 watts per lamp compared to rapid-start ballasts. Lamps using these ballasts typically withstand 10,000 to 15,000 on/off cycles before failure.
Programmed Rapid Start
Supports more start cycles per lamp, helping to extend overall lamp life.
- Designed for frequent switching applications, such as areas with occupancy sensor controls.
- Starts lamps quickly (1.0–1.5 seconds) without flicker.
- Supports up to 50,000 on/off cycles, maximizing lamp life.
Considerations for Choosing the Right Ballast
Determining Light Output
Ballasts regulate the electric current to stabilize a lamp’s light output.
Ballast Factor (BF) measures the light output of a ballast-lamp system.
To calculate actual light output, multiply the BF by the lamp’s rated lumens.
Rated lamp lumens x Ballast Factor (BF) = Light
Low Ballast Factor: 0.71 – 0.78
Normal Ballast Factor: ~0.88
High Ballast Factor: 1.15 – 1.25
Low Ballast Factor: Reduces light output but saves energy.
High Ballast Factor: Delivers maximum light output from the lamp.
Determining Lamp Energy Usage
Lamp energy use varies based on the type of ballast.
The combination of lamp and ballast determines system wattage.
Feature Comparison
Feature | Standard Elect | Centium | Optanium |
|---|---|---|---|
Voltage | 120 or 277 | 120/277 Intellivolt | 120/277 Intellivolt |
Efficiency | Better | Good | Best |
Safety Type CC Rating | No | No | Yes |
Cold Start | 0° | 0° | -20° |
Anti-Striation* | No | No | Yes |
Note: Striation refers to the visible swirling or spiraling effect in fluorescent lamps during initial startup.