Starters and Ballasts
LED lamps and halogen lamps are fairly recent developments in low energy lighting but fluorescent lamps have always offered cost-effective illumination. Unfortunately, some of their common characteristics have resulted in them not always being popular. The flickering of failing tubes or the repeated cycling of an unsuccessful start-up can be annoying, as can the strobing effect found with some lamps. Modern components can reduce or completely eliminate such problems, also offering faster, flicker-free starts and longer tube life. The option of dimming is now also available and some electronic control units allow the lamp to be operated on either an AC or DC supply, making them ideal for use in an emergency lighting circuit. For those lamps employing a plug-in type of starter, the traditional 'glow-tube' type is still available but newer electronic starters offer the advantages of a soft, flicker-free start, which results in less electrode wear and tube end-blackening. Although all of these plug-in starters are physically identical and therefore interchangeable, care must be taken to check the compatibility with the lamp being used. All fluorescent lamps require a ballast circuit and in early lamps this was quite basic, but modern electronic control units carry out many functions to ensure that the lamp operates to its full potential.