OSRAM POWERTRONIC PT-FIT I ECG for HID lamps, with cable clamp - Manual (Page 28)

THE PRODUCT IN OPERATION
2.4. Hints on luminaire design
The general recommendations on luminaire design by IEC
and the national authorities (VDE, KEMA, ANSI, etc.)
should be followed.
In addition, it should be noted that POWERTRONIC ® sys-
tems may be subject to ignition voltages of up to 4.5 kV.
Components (sockets, cabling, etc.) and materials should
be selected in accordance with these requirements. Data
on the lamps to be used can be found in the relevant IEC
standards 61167 (for metal halide lamps) and 60622 (for
high-pressure sodium vapor lamps). In addition to these,
the international standard for luminaires IEC 60598 is also
relevant.
Notes on the wiring can be found in section "2.2.4. Wiring"
while notes on conformity with EMC guidelines in section
"2.2.4.4. Cable layout".
2.4.1. Thermal coupling
POWERTRONIC
® ECGs have an effi ciency of 90 to 92 %.
The remaining wattage is lost energy which causes the
self-heating of the devices. Due to their excellent effi -
ciency, ECGs are subject to relatively little self-heating.
However, to achieve the maximum possible device service
life and the minimum failure rate, this heat must be con-
ducted away from the device as effi ciently as possible.
Especially for the integration in luminaires the following
should be kept in mind:
• Use appropriate measures to achieve good heat transfer
between the POWERTRONIC ® device and the luminaire
casing.
− Direct, wide-surface contact between the ECG and the
luminaire casing.
− Make luminaires out of highly conductive materials,
such as metals.
• Prevent air-fi lled gaps between the ECG and the lumi-
naire casing
– Air has an insulation effect
− Do not mount the ECG on internal housing beams
− Do not use any spacers between the ECG and the
luminaire casing in order to fasten the ECG into the
luminaire.
− Place any mounting or holding plates in such a way as
to ensure wide-surface contact between the ECG and
the luminaire casing.
• Do not place any insulation material between the ECG
and the luminaire casing
− Do not use double-sided tape to secure the ECG
− Do not place any materials with low heat conductivity
between ECG and luminaire
• In order to achieve particularly good heat conductivity at
critical positions thermal pads can be placed between
the ECG and the luminaire casing.
• Ensure a clearance between the ECG and the lamp
(ideally ≥ 30 cm); provide a separate chamber for the
ECG; otherwise use cooling plates or heat sinks in
order to keep heat radiation away from the device.
In all cases it will be necessary to measure temperature t
c
at the test point in order to ensure that t
c
max. is not ex-
ceeded.
28
2.4.2. Ventilation slits, cooling fi ns
Ventilation slits in the luminaire ensure direct ventilation of
the interior of the luminaire and thus allow the ECG to be
cooled directly. The ventilation slits (for air in and out)
should have a minimum width of 4–5 mm and should be
arranged so that there is an air current fl owing over the
ECG no mater where the luminaire is positioned. Cooling
fi ns on the outside surface of the luminaire increase its
surface and thus contribute to improved thermal radiation
properties for the luminaire.
2.4.3. Materials that may be used in luminaire structures
Depending on design and intended applications, both
plastics and metals can be used in building luminaires for
HID systems. Each material has its own individual proper-
ties. The main consideration to be kept in mind, however,
is that the material being used satisfi es the thermal re-
quirements demanded by the heat radiated from the light
source. In addition, these materials need to have the
appropriate resistance to UV light.
More information on this topic can be found in the appli-
cation guide: "Metal halide lamps – hints on application
and use"
From the ECG point of view, the best possible heat trans-
fer should be the target (see also section "2.4.1 Thermal
Coupling")
2.4.4. Installation-friendly ECG
Depending on the intended application and the mounting
conditions in the luminaire, a built-in ECG or one with a
cable clamp can be used. Both the built-in devices (PTi S
or B, PT-FIT S or B and PTo) and the devices with cable
clamp (PTi I or SNAP and PT-FIT I) are particularly easy to
mount.
S version for installation in luminaires
Figure 28: PTi 70/220-240 S
• Mounting the device using a grommet on its bottom or side
• Plug terminals for fast connection and release of wires
without tools
• Stable and robust metal casing