Photocontrol Glossary
ANSI C 136.10:
ANSI: American National Standards Institute Reference for Roadway and Area Lighting Equipment
C13.10: 0: Refers to Locking type photocontrol devices and mating receptacles.
AMBIENT LIGHT:
The general overall lighting in an area.
BRIGHTNESS:
Visual perception of the luminance of light source.
BURN TIME:
The number of hours a photocontrol (lighting control) in programmed to allow lamp fixture to burn.
BUTTON:
Small compact photocontrol, usually hard-wired. Used mostly with selected Post Top Luminaries. Can be installed inside the luminaire housing.
CADMIUM PHOTOSENSOR:
Spectral response closest to the human eye. Conformal Coated. Will drift over time.
CANDLEPOWER/FOOTCANDLE: (cp),
Luminous intensity expressed in candelas.
CAP COLOR PER ANSI STANDARD:
105-305 Volt (Multi): Blue
120 Volt: Gray
Optional: Black
240 Volt: Maroon
Optional: Brown
347 Volt (Canada): Green
Optional: Orange
480 Volt: Yellow
DRIFT:
Drift means that the cell suffers an irreversible change toward lower sensitivity and higher control turn-ON and OFF.
FAA:
Photocontrols that meet the requirements of obstruction lighting as regulated by the Federal Aviation Association.
FAIL-OFF PHOTOCONTROL:
A photocontrol that is designed so that the load remains off when the most likely failure occurs.
FAIL-ON PHOTOCONTROL:
A photocontrol designed so that the light remains on when the most likely failure occurs.
FILTERED (Verses Ripley's IRES):
Filtered photocontrols use a filtered window to detect sensitivity to infrared.
Con to filtered window: Filter does not capture ambient infrared, only what comes through the window. Over time, UV fades the filter causing inadequate accuracy. Drift results. Ripley's IRES does not filter infrared, it totally cancels/eliminates infrared.
FOOTCANDLE (fc):
A unit of illuminance. One footcandle is one lumen per square foot.
HAZARDOUS LOCATION:
An area where ignitable vapors or dust may cause a fire or explosion created by energy emitted from lighting or other electrical equipment.
Illuminating Engineering Society of North America (IESNA):
Professional society of lighting engineers, manufacturing companies and other professionally involved in lighting, devoted to lighting information and evaluation, as well as the development of national standards.
INFRARED (IR):
The name means "below red" (from the Latin infra, "below"), red being the color of visible light of longest wavelength. The Invisible part of light with longer wavelengths that are felt as heat radiation.
The invisible heat radiations beyond the red end on the visible spectrum. Impossible or nearly impossible to see by the human eye. Light that is so red, we cannot see it. The sun produces a continuous spectrum of light that spans infrared, visible, and ultraviolet light.
What our eyes perceive as white sunlight is actually a mixture of all the colors of the rainbow.
INVERSE RATIO:
A photocontrol with the turn-off at a lower value than the turn-on.
IRES (INFRARED ELIMINATING SYSTEM):
Ripley's (patent pending) Infrared Eliminating photocontrol. Truly and precisely cancels / eliminates the unit's reaction to infrared maintaining true accuracy. Replaces filtered units used by others.
JOULE (J):
A metric unit of work or energy, equivalent to one watt second.
LIGHT POLLUTION:
Any adverse effect of man-made light. Often used to denote urban sky glow.
LUMEN (lm):
SI unit of luminous flux. Radiometrically, it is determined from the radian power. Photometrically, it is the luminous flux emitted within a unit solid angle (one steradian) bya point source having a uniform luminous intensity of one candela.
LUMINAIRE:
The more modern term for Lantern. A housing or fixture that holds a light source (lamp).
LUX (lx):
The SI unit of illuminance. One lux is one lumen per square meter.
MICROCONTROLLER (MICROPROCESSOR):
Latest technology… usually used for advanced features such as built-in timing functions, inverse ratio, etc… more expensive than electronic. Microcontrollers are electronic controls with added computer programming.
MOV (Metal Oxide Varistor):
Surge arrestor used to suppress voltage transients and reduces the likelihood of damage to the fixture or the control caused by voltage surges or line noise.
MULTI-VOLT:
One unit designed to operate within the range of 105-305 volts.
NON-SHORTING CAP:
A device (with a weather seal) that provides an open circuit between line and load when a photocontrol is not used. Also called an "open cap". Non-shorting caps are color coded red.
PHOTOCONTROL / PHOTOCELL / PHOTO ELECTRIC CELL / LIGHT SENSOR:
A light-sensing device used to control luminaries, which turns the lamp off during the day, and turns the lamp on at night, in response to detected light levels. A socket for the photocontrol is usually built into, and is part of the luminaire housing.Photocontrols sense ambient light and turn electric lights (or other electric devises) on when natural light levels are low, and off when light levels are higher, most commonly, but not necessarily, corresponding to dusk and dawn.
PLUG:
A cluster of blades fixed to a photocontrol, shorting cap, or non-shorting cap to establish an electrical mechanical connection when inserted into a mating receptacle.
RECEPTACLE:
An outlet that is intended to be equipped electrically and mechanically to receive the plug.
SHORTING CAP:
A device that provides a closed circuit between line and load when a photocontrol is not used. Shorting Caps are color coded black.
SURGE PROTECTION:
A unit designed to protect electrical devices from power surges and voltage spikes. Surge protectors attempt to regulate the voltage supplied to an electric device by either blocking or shorting to ground voltage above a safe threshold. Photocontrols most commonly use MOV's.
TIME DELAY:
A device that delays a control response by a period of time. Prevents sudden changes in the ambient light level from turning a fixture off during night-time operation.
TURN-OFF AND/OR TURN-ON RESPONSE TIME:
The time between a rapid change in light level and the switching of the load. Turn-Off delay may be different than turn-on delay.
TURN-OFF / TURN-ON RATIO:
The turn-off light level divided by the turn-on light level.
TWIST-LOCK:
A three-prong locking type of electrical plug commonly used with photocontrols to prevent the power source and the photocontrol from being accidentally disconnected.