Incandescent lamps (general-use lamps) were favoured in residential lighting. With 12 lm/W and an average service life of 1,000 hours, they were less appropriate for commercial and industrial installations.
Incandescent lamps
High-voltage halogen lamps for mains voltage operation and low-voltage halogen lamps with12 V or 24 V were traditionally used in sales spaces and representative installations. Their service life is at least double that of incandescent lamps and their luminous efficacy is 50% higher.
Due to their instant luminous flux emission (no ignition time is needed as with discharge lamps), they were also applied for object surveillance, for example in combination with motion detectors. Mostly, they have been replaced by LED lamps or LED luminaires.
Figure 3.249: Luminous efficacy of several thermal radiators in comparison to heated tungsten W (benchmarks, curve shows maximum luminous efficacy of tungsten)
1 incandescent lamp 15 W, 90 lm, 6 lm/W
2 incandescent lamp 100 W, 1 360 lm, 13,6 lm/W
3 halogen lamp12 V, 20 W, 320 lm, 16 lm/W
4 halogen lamp12 V, 100 W, 2 200 lm, 22 lm/W
5 halogen projector lamp 24 V, 250 W, 10 000 lm, 40 lm/W