Point-by-Point Photometrics
This section describes how to calculate and display indoor, outdoor, and egress point-by-point photometrics.
Common Photometric Boundary Informationā
The values that can be specified for a photometric boundary are listed below.
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Ā āĀ OverrideĀ ScheduleĀ Title Whether the schedule title for the current calculation area is to be changed from the default calculation schedule title.
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Ā ScheduleĀ Title: The title to be used in the calculation schedule for the calculation area. This field can be modified if the āĀ OverrideĀ ScheduleĀ Title box is checked.
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Ā Grid/IlluminanceĀ LevelĀ Spacing: The distance between points where illuminance levels will be calculated. See the Distance Input Format section for more information about specifying this distance.
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Ā CalculationĀ Elevation: The elevation of the floor within the calculation area. See the Distance Input Format section for more information about specifying this elevation.
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Ā TopĀ Elevation: This is the elevation at the top of the slope. See the Distance Input Format section for more information about specifying this elevation.
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Ā BottomĀ Elevation: This is the elevation at the bottom of the slope. See the Distance Input Format section for more information about specifying this elevation.
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Ā šĀ BoundaryĀ Obstructions Whether the area has a ceiling and walls.
- Ā None The area has no ceiling or walls.
- Ā Ceiling The area has a ceiling.
- Ā Ceiling and Walls The area has a ceiling and walls. This setting prevents light generated from light fixtures outside the boundary from affecting the photometric calculations.
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Ā CeilingĀ Height: The height of the boundary ceiling. This setting is available if šĀ BoundaryĀ Obstructions is set to Ceiling or Ceiling and Walls. See the Distance Input Format section for more information about specifying this height.
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Ā SurfaceĀ Reflectance: The percentage of light reflected by the boundary. This setting is available if šĀ BoundaryĀ Obstructions is set to Ceiling or Ceiling and Walls, and is only used if reflections are enabled in the calculation.
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Ā āĀ CalculateĀ VerticalĀ IlluminanceĀ LevelsĀ (AtĀ AreaĀ Boundary) Whether vertical illuminance levels are to be calculated along a calculation line or at the edges of a calculation area.
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Ā VerticalĀ CalculationĀ Spacing: The distance between points where vertical illuminance levels will be calculated.See the Distance Input Format section for more information about specifying this distance.
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Ā VerticalĀ DisplayĀ Spacing: The distance between vertical calculation points as they are displayed on the drawing.See the Distance Input Format section for more information about specifying this distance.
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Ā EndingĀ VerticalĀ CalculationĀ ElevationĀ (AboveĀ Slope): The maximum height at which vertical illuminance levels will be calculated. See the Distance Input Format section for more information about specifying this elevation.
If the calculation area is sloped, the EndingĀ VerticalĀ CalculationĀ ElevationĀ AboveĀ Slope specifies the maximum vertical distance above each point along the slope. For example, an area with a TopĀ Elevation of 30 and an EndingĀ VerticalĀ CalculationĀ ElevationĀ AboveĀ Slope of 10 will calculate illuminance levels from 30' to 40' at the top of the slope.
Common Photometric Solid Informationā
The values that can be specified for a photometric solid are listed below.
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Ā StartingĀ Elevation: The elevation at which the photometric solid starts. See the Distance Input Format section for more information about specifying this elevation.
If this is 0 and the object is a closed area, no values inside the object will be calculated or displayed.
If this is greater than 0, the light levels underneath the object will be calculated. This setting can be used to model overhangs.
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Ā EndingĀ Elevation: The elevation at which the photometric solid ends. See the Distance Input Format section for more information about specifying this elevation.
If this elevation is lower than the elevation of a light fixture, some light will pass over the object.
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Ā Reflectance: The percentage of light reflected by the photometric solid. It is only used if reflections are enabled in the calculation.
Point-by-Point Photometrics Calculationsā
There are two types of point-by-point photometric calculations available: general and egress. Each calculation uses separate fixtures, separate fixture lumens, and separate layers.
General vs. Egress Light Fixtures, Lumens, and Layersā
Each calculation uses a separate set of light fixtures. Each light fixture on the drawing can be marked as being included in the general lighting calculation, egress lighting calculation, both calculations, or neither calculation. This is important for egress calculations, as only certain light fixtures will be on during an emergency situation. See the Insert Light Fixture section for more information about specifying whether a light fixture is used for general or egress calculations.
In the light fixture schedule, the total lumens for the fixture can be set differently for the general calculation and egress calculation. This is important for egress calculations for fixtures, as only certain lamps will be on in an emergency situation. See the Common Light Fixture Information section for more information about lumens settings.
Light fixtures included in the egress calculation can be inserted on a separate layer from other light fixtures. The separate layer allows you to create a view of the drawing with only general or egress light fixtures included. See the Layers section for more information.
Multiple Calculation Areas and Linesā
Multiple general and egress calculation areas and lines can be defined on a single drawing. The general boundaries include the light from all general lights on the drawing. The egress boundaries include the light from all egress lights on the drawing.
Reflectionsā
Reflections from buildings and walls can be included in the calculation. The walls for each boundary have a reflectance value that is used to calculate the amount of light that they reflect. For outdoor photometrics, this reflection results in slightly higher values near buildings. For indoor photometrics, wall reflections are an important component of the calculation.
Reflections from the ceiling can also be included in the calculation. The ceiling height and reflectance values are set when an area is first inserted and can be modified using the Query Calculation Area or Solid command.
IES Filesā
The illuminance level at each point within a defined boundary is calculated using the IES file for each light fixture. See the Common Light Fixture Information section for more information about light fixture IES files.
Commandsā
šļø Insert General Photometric Calculation Area
The Insert General Photometric Calculation Area command is used to insert a flat area on the drawing where general illuminance levels are to be calculated.
šļø Insert General Sloped Photometric Calculation Area
The Insert General Sloped Photometric Calculation Area command is used to insert a sloped area on the drawing, such as stairs, where general illuminance levels are to be calculated.
šļø Insert General Photometric Calculation Line
The Insert General Photometric Calculation Line command is used to insert a line on the drawing where general illuminance levels are to be calculated.
šļø Insert General Sloped Photometric Calculation Line
The Insert General Sloped Photometric Calculation Line command is used to insert a sloped line on the drawing where general illuminance levels are to be calculated.
šļø Calculate General Photometrics
The Calculation General Photometrics command is used to calculate point-by-point photometrics inside of general calculation areas and along general calculation lines. All of the settings available in the command are the same as the Calculate Egress Photometrics command. This section describes the options available for both commands.
šļø Insert Egress Photometric Calculation Area
The Insert Egress Photometric Calculation Area command is used to insert a flat area on the drawing where egress illuminance levels are to be calculated.
šļø Insert Egress Sloped Photometric Calculation Area
The Insert Egress Sloped Photometric Calculation Area command is used to insert a sloped area on the drawing, such as stairs, where egress illuminance levels are to be calculated.
šļø Insert Egress Photometric Calculation Line
The Insert Egress Photometric Calculation Line command is used to insert a line on the drawing where egress illuminance levels are to be calculated.
šļø Insert Egress Sloped Photometric Calculation Line
The Insert Egress Sloped Photometric Calculation Line command is used to insert a sloped line on the drawing where egress illuminance levels are to be calculated.
šļø Calculate Egress Photometrics
The Calculate Egress Photometrics command is used to calculate point-by-point photometrics inside of egress calculation areas. All of the settings available in the command are the same as the Calculate General Photometrics command.
šļø Query Calculation Area or Solid
The Query Calculation Area or Solid command is used to view and edit the information associated with calculation areas and photometric solids.
šļø Aim Light Fixture
The Aim Light Fixture command is used to aim a light fixture at a specific point on the ground.
šļø Insert Photometric Solid: Shape
The Insert Photometric Solid: Shape command is used to insert solids that are closed but not rectangular. If the Starting Elevation is 0, any illuminance levels inside the shape will not be printed. Most solid objects will be inserted using this command, as most buildings and other objects on your plans will require a non-rectangular shape.
šļø Insert Photometric Solid: Rectangle
The Insert Photometric Solid: Rectangle command is used to insert solid objects that are rectangular. These objects are closed. If the Starting Elevation is 0, any illuminance levels inside the rectangle will not be printed.
šļø Insert Photometric Solid: Line
The Insert Photometric Solid: Line command is used to insert light-obstructing objects that are shaped like a line. These objects are not closed.
šļø Insert Photometric Mask
The Insert Photometric Mask command is used to define an area in a calculation area where the illuminance values should not be calculated.
šļø Add Photometric Vertex
To add a vertex to a photometric area, solid, or mask, go to
šļø Remove Photometric Vertex
To remove a vertex from a photometric area, solid, or mask, go to
šļø Add Calculation Area to Group
The Add Calculation Area to Group command is used to group multiple calculation areas together. Calculations areas in a group share a common calculation schedule.
šļø Remove Calculation Area from Group
The Remove Calculation Area from Group command is used to remove a calculation area from a calculation area group.
šļø Highlight Calculation Area Group
The Highlight Calculation Area Group command is used to highlight all of the calculation areas in a calculation area group.
šļø Add Photometric Calculation Schedule
To add a photometric calculation schedule to a calculation area, go to
šļø Delete Photometric Calculation Schedule
To delete a photometric calculation schedule from the drawing, go to
šļø Edit Photometric Calculation Schedule Note
The Edit Photometric Calculation Schedule Note can be used to add or modify a note below a photometric calculation schedule on the drawing.