Instruction manual
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control gear. Therefore, a direct comparison with conventional control gear
(chokes) does not make sense.
In T5 luminaires, the electronic control gear functions as a vibration source
and is capable of exciting adjacent metallic or plastic components so that
they act as resonators, amplifying the actual noise considerably and help to
spread it out.
To avoid this, especially the recommended minimum distance between two
T5/
∅ 16 mm- fluorescent lamps has to be respected so that no noise can
be generated due to physical contact.
1. For high luminaire efficiency the distance should be at least 48 mm
between the two lamps (approximately two fingers should fit
between the lamps)
2. When designing the luminaire for minimum distance the maximum
recommended base temperature of 120 °C may never be
exceeded.
6.2.2 Recommended
minimum distance
between lamp and
refelctor
The maximum recommended base temperature of 120 °C may never be
exceeded.
A distance of less than 3 mm between lamp and reflector can result in
generation of noise even in luminaires with non-dimmable ECGs.
At a distance of less than 6 mm between lamp and reflector the leakage
current of the dimmed lamps 35 W, 49 W and 80 W causes visible
differences in brightness between the ends of the lamps. In addition, the
radio interference suppression is getting worse.
OSRAM recommendation:
In general, OSRAM recommends to keep a minimum distance of
6 mm
between lamp and reflector. In certain cases (unfavourable capacitive
interference) the minimum distance should be even greater.
To develop luminaires that are as quiet as possible, it is therefore essential
to insulate the control gear and chassis or luminaire support. In other
words, there should be clearance below the ECG with the ECG mounted on
point supports on the luminaire chassis or on rubber absorbers as used for
conventional ballasts. Under certain circumstances, this type of mounting
may, however, lead to thermal problems since the best way to dissipate the
power loss to the environment is to have the ECG in full contact with the
chassis.
32 mm