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Appliances & Equipment
Electronic Ballasts
Electromagnetic
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Digital Dimmable |
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Functions of Ballast for Fluorescent Lamps
- Supplies controlled power to heat lamp electrodes
- Supplies starting voltage to ionise lamp gas and create electron discharge stream between electrodes
- Limits current and controls power to the lamp for proper operation
Conventional control gear for fluorescent lamp includes magnetic ballast, starter switch & power factor correction capacitor, and consumes high portion of power to operate (typical @ 11W)
Conventional Ballast Circuit
- Normally, 1 conventional ballast is used for 1 lamp only
- 2 x 18W T8 lamps could be operated in series via 36W conventional ballast
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Electronic Ballasts
Electronic Ballast Circuit
- Sample shows one ballast for 1 lamp
- Circuit could be one ballast for 1 lamp, 2 lamps, 3 lamps or even 4 lamps
Electronic Ballasts
High frequency operation of lamp increases lamp life by:
- reducing load on lamp electrodes (less blackening)
- reducing greying of fluorescent material
Lumen Output as Function of Frequency
Electronic Ballasts
Electronic ballast designed to IEC 60928 & 60929 are well developed nowadays & have widely been used for replacing conventional ballasts in fluorescent luminaires
Basic Requirements for High Performance Criteria :
- No visible flicker
- Low lamp current crest factor (LCCF)
- Low total harmonic distortion (THD)
- High power factor
Other Types of Electronic Ballasts Available:
- Dimmable electronic ballasts using 0 - 10 V d.c. analogue signal
- Digital dimmable & DALI electronic ballasts
- Electronic ballasts for non-integrated Compact Fluorescent Lamps (CFL)
- Electronic ballasts for High Intensity Discharge (HID) lamps
- Integrated Electronic Ballast with Emergency Power Pack
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