311
Informations
Explanation of Data Blocks
The luminaire data necessary for lighting planning are allocated
respectively to an article with particular equipment.
Equipment
The designation of lamp equipment is named in the catalogue according
to the lamp designation system of the ZVEI (LBS).
Light Distribution Curve (LDC)
The radiation characteristics of a luminaire or lamp, the distribution of
luminosity, is given in a polar coordinate system. Rotationally symmetric
luminaires such as downlights are shown in one plane, and linear
fluorescent luminaires in two planes.
Efficiency Level hLB
The luminaire operating efficiency level s given in % and ascertained in the
factory’s own photometric laboratory. First the luminous flux of the lamps
is measured, then the luminous flux of the luminaire with the inbuilt lamps.
The relation between luminaire luminous flux and lamp luminous flux
produces the luminaire operating efficiency level.
Example:
Luminous flux of inserted lamps = 9000 lm
Luminous flux of the luminaire = 6000 lm
• Luminous flux loss of 3000 lm corresponding to 33%
• Luminaire operating efficiency level = 67%
With LED luminaires the luminous fluxes of the LEDs can often not be
determined separately, since e.g. their cooling is ensured via the luminaire
housing. Since in these cases the luminaire can only be measured
photometrically as a whole and therefore no decrease in the luminous flux
is to be considered, the luminaire operating efficiency level is set at 100%
here.
Luminance at γ = 65°
High luminance diferences in the feld of vision are perceived as glare.
Ceiling-mounted luminaires are perceived as glaring as soon as they
emit too high a light proportion above 65° (from the perpendicular). In
this range the risk of both direct glare and indirect glare (e.g. via screen
surfaces) is particularly high. DIN EN 12464-1 therefore prescribes limits for
this range. These are for 3000 cd/m² workstations with screen luminance >
200 cd/m² and 1500 cd/m² for workstations with screen luminance < 200
cd/m² (current standard with fat screens ≥ 250 cd/m²).
Half-Peak Angle a
With spotlights, instead of the diffusion angle the half-peak angle is given
for assessing the light cone (angle to the perpendicular).
Cut-Off Angle
The cut-off angle of a luminaire is defined according to DIN EN 12464-1
”Lighting of indoor workplaces” as the angle between the horizontal plane
(usually also mounting surface) and the direction from which the lamps
and the surfaces of high luminance cease to become visible. If the correct
cut-off angle is not observed, there is a danger with direct beam luminaires
of direct glare from excessive luminance.
UGR
The UGR procedure was developed by the International Commission on
Illumination CIE, is a component of DIN EN 12464-1 and serves to assess
psychological direct glare taking into account a room’s geometry and
surfaces. The UGR values given in the catalogue were ascertained for a
standard room with the following properties: Room geometry: X=2H, Y=2H
Reflection grades: rceiling=70; rwalls=50; rfloor=20