5 Terms
Contributors in Lighting
Lighting
Hot restart or hot restrike
Construction; Lighting
The phenomenon of re-striking the arc in an HID light source after a momentary power loss. Hot restart occurs when the arc tube has cooled a sufficient amount.
Power factor
Construction; Lighting
The ratio of AC volts x amps through a device to AC wattage of the device. A device such as a ballast that measures 120 volts, 1 amp, and 60 watts has a power factor of 50% (volts x amps = 120 ...
Lamp current crest factor (LCCF)
Construction; Lighting
The peak lamp current divided by the RMS (average) lamp current. Lamp manufacturers require <1.7 for best lamp life. An LCCF of 1.414 is a perfect sine wave.
Lens
Construction; Lighting
Transparent or translucent medium that alters the directional characteristics of light passing through it. Usually made of glass or acrylic.
Trigger start
Construction; Lighting
Type of ballast commonly used with 15-watt and 20-watt straight fluorescent lamps.
Ballast cycling
Construction; Lighting
Undesirable condition under which the ballast turns lamps on and off (cycles) due to the overheating of the thermal switch inside the ballast. This may be due to incorrect lamps, improper voltage ...
Ballast efficiency factor (BEF)
Construction; Lighting
The ballast factor divided by the input power of the ballast. The higher the BEF within the same lamp-ballast type, the more efficient the ballast.
