What is Rapid Start (RS)

Rapid Start (RS) is a type of ballast commonly used in fluorescent lighting systems designed to apply a low filament voltage to preheat the cathodes within the lamp. This preheating process helps to extend the lifespan of the lamp and improve its overall performance. Simultaneously, a starting voltage, lower than that used in instant start ballasts, is also applied to strike the arc and initiate the lamp’s operation.

Rapid Start ballasts have a slight turn-on delay compared to instant start ballasts. Additionally, they may not reliably start lamps under 50 degrees Fahrenheit. This means that in colder environments, lamps with Rapid Start ballasts may experience difficulties starting up or may take longer to reach their full brightness.