Engineers from PureSpectrum have developed an electronic ballast circuit design that enables compact fluorescent lamps (CFLs) to be fully dimmable using a standard dimming device. According to the company, this development allows for previously unattainable dimming capability, while also providing lighting control compatibility for CFL bulbs.
The ballast circuit enables a CFL bulb to be dimmed to below 10% of perceived light output with a standard dimming switch. It also allows a CFL to function side-by-side with incandescent bulbs and mimic their performance characteristics such as low-light starts.
While most leading brand-name lighting manufacturers include a dimmable CFL in their product lines, the popularity of these bulbs among consumers has been hindered by performance volatility and a prohibitively high price point, says the company. The bulbs often could not be dimmed lower than 20% of perceived light output and frequently did not function properly with existing lighting controls built to dim incandescent bulbs.
The high retail cost of dimmable CFL bulbs resulted from additional components in the bulb’s electronics, which enabled dimming to occur. In contrast, PureSpectrum’s more-efficient circuit topology will benefit both manufacturers and consumers.
PureSpectrum’s ballast model has a component count similar to a standard non-dimmable CFL bulb and features high power factor built into the ballast. The reduced component count would increase manufacturing efficiencies and allow retail prices for dimmable bulbs to be in line with non-dimmable CFL bulbs.
PureSpectrum is currently conducting photometric testing on the initial dimmable prototype at lighting testing facility Intertek. The test results will include a performance comparison between the PureSpectrum prototype and dimmable CFL bulbs from MaxLite and GE.