Instruction manual

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If, however, the temperature at the tc point is permanently 10 °C or more
below the maximum, the expected service life of the unit will be
approximately doubled.
3.9.2.2 Ambient Temperature
ECG : ta
According to EN 60598-1, ta (a stands for ambient) is the maximum value
of the steady state temperature at which, during normal operation, limit
temperature tc is not exceeded at the measuring point.
Also according to EN 60598-1, there are precisely defined testing and
measuring requirements for both surface mounted luminaires (pendant and
portable, for example floor lights) and recessed luminaries.
3.9.3 Lamp Temperature
The maximum values specified in the lamp documentation for cold-spot
temperature (see Technical Specification T5 Fluorescent Lamps) are
important operating criteria for the lamp and must not be exceeded nor
fallen below under any circumstances in order to achieve optimum
luminous flux. The ambient temperature to reach the maximum lumen
output is 35°C for T5/∅ 16 mm fluorescent lamps FH
®
..HE and FQ
®
...HO,
and 25 °C for FC
®
- circular fluorescent lamps
Further lamp and ECG should not heat each other. ECG should be
dissipated through good thermal connection between ECG and luminaire
housing.
3.9.3.1 Maximum Luminous
Flux for T5/
∅ 16 mm-
Fluorescent Lamps
Usually, T5-fluorescent lamps reach their standard electric properties (rated
values) which are used for lighting design purposes at ambient
temperatures of 25 °C. Their maximum light outputs, however, are
achieved at ambient temperatures of 35 °C.
Luminous flux FH
®
…HE and FQ
®
…HO fluorescent lamps related to the lamp ambient
temperature
Placement of th filaments for T8 lamps
Placement of the filaments for T5 lamps
Cold Spot
T5 FH28W (nearly constant power supply): Luminous flux / Voltage - Horseshoe
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
55% 60% 65% 70% 75% 80% 85% 90% 95% 100%
relative lamp voltage
relative light output
COLD SPOT temperature
50°C 45°C
40°C
35°C
30°C
25°C
15°C
90°C
85°C
80°C
75°C
70°C
65°C
60°C
55°C
5°C
10°C
0°C
20°C
ambient temperature
-5°C
75°C
25°C
35°C
45°C
5°C
-25°C
55°C
T5 FQ54W (nearly const ant power supply): Luminous f lux / Volt age - Hor seshoe
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
60% 6 5% 70% 75% 80% 85% 90% 95% 100%
relative l amp voltage
relative light output
COLD SPOT t emper ature
-5°
C
50°
C
45°
C
40°
C
35°
C
30°
C
25°
C
15°
C
90°
C
85°
C
80°
C
75°
C
70°
C
65°
C
60°
C
55°
C
5°
C
10°
C
0°
C
20°
C
ambient temperature
-5°
C
78°
C
25°
C
35°
C
45°
C
5°
C
-25°
C
55°
C