Luminaire Selection Flashcards

When specifying luminaires for a historically sensitive renovation, which consideration is typically prioritized alongside energy code compliance?

Answer: Maintaining the visual character and scale of original fixtures

Historic preservation projects require balancing energy code mandates with maintaining the visual integrity and character of the original lighting fixtures and space.

A luminaire's photometric data shows a beam spread of 15°. How would this typically be classified?

Answer: Spot

A 15° beam spread is classified as a spot beam, typically used for accent lighting or highlighting small, focused areas.

For an outdoor parking structure, which luminaire characteristic is most critical in reducing energy consumption while maintaining safety illuminance levels?

Answer: Precise photometric distribution minimizing wasted spill light

Precise optical control directs lumens exactly where needed, allowing designers to meet illuminance targets with lower wattage and fewer fixtures.

A luminaire spec sheet lists a Power Factor (PF) of 0.95. What does this tell the electrical designer?

Answer: The luminaire draws real and reactive power with only 5% reactive component

A power factor of 0.95 means 95% of the volt-amperes drawn are converted to real working watts, with only 5% reactive power, indicating an efficient driver design.

Which luminaire type would a CLD specify for grazing a rough stone or textured masonry wall to emphasize texture?

Answer: Narrow-beam accent luminaire mounted very close to the wall surface

Grazing places a narrow beam very close and nearly parallel to a textured surface, casting strong shadows that emphasize the surface texture and relief.

A sports facility requires luminaires meeting specific vertical illuminance targets for television broadcast. Which photometric parameter is most critical to evaluate?

Answer: Mean vertical illuminance (Ev) in camera directions

Television broadcast requires adequate vertical illuminance (Ev) in the camera viewing directions to properly illuminate athletes' faces and capture fast action.

When evaluating two luminaires with identical lumen outputs but different beam angles for a retail spotlight application, what is the primary effect of a narrower beam angle?

Answer: Higher center-beam candlepower (CBCP)

Concentrating the same lumens into a narrower beam increases the center-beam candlepower (CBCP), creating a brighter, more intense accent effect on the target.