4. Compact ELV (Extra Low Voltage) Tungsten Halogen Lamp Advantages Disadvantages • Smaller and more robust filament and has better beam control • Higher efficacy, therefore lower running costs • Better lumen maintenance due to no lamp blackening • Longer lam life up to 3500 hours • Less heat generated especially with “dichroic” filters • Used often for outdoor or in underwater lighting in pools • Sizes: 20W, 50W, 75W • Heavier wiring required to carry higher current necessary for the low voltage. • Adequate ventilation required for the transformer. • Higher initial cost.
