Vacon 20 CP, Installation, Technical And Maintenance Manual

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3
vacon • 25 Mounting
3.2 Cooling
The AC drive produces heat in operation due to the energy dissipation of the electronic compo-
nents (rectifier and IGBT) and is cooled by a heatsink via the cold plate of the frequency con-
verter. The capacity to dissipate this heat mainly depends on the size of the heatsink surface,
the environment temperature and the heat transmission resistance. An increase of the heat
transmission rate can only be realized to a certain extent by increasing the surface of the heat-
sink. An additional increase of the heat dissipation by increasing the heatsink is not possible.
The frequency converter should be mounted with the cold plate on a heatsink with lowest ther-
mal resistance possible.
3.3 Environment temperature
The drive environment temperature shall not exceed 70 °C (158 °F) for the drive installed lo-
cation. The aluminium panel of the back of the drive is called “cold plate”. The cold plate should
never exceed 85 °C (185 °F).
3.4 Heatsink assembly instructions
The VACON
®
20 CP frequency converters are designed for installation on surfaces which com-
ply with the specifications listed in this paragraph.
The heatsink surface that is in contact with the frequency converter cold plate must be free
from dirt and particles. The mating surface flatness shall not exceed 50
μ
m (DIN EN ISO 1101)
across the entire mating surface, and the roughness less than 6.3
μ
m (DIN EN ISO 4287). The
maximum peak-valley height of the surface shall not exceed 10
μ
m (DIN EN ISO 4287).
Apply a thermal compound between the heatsink and the AC drive cooling mating surface. The
thermal paste assists the drive heat dissipation. Vacon recommends the thermal compounds
listed in the following table:
Vacon recommends screen printing for applying the thermal paste. In certain cases an appli-
cation by hard rubber roller might be applicable. After mounting the AC drive to the heatsink
panel, wipe away any excess compound from around the plate.
The drive may be damaged if the temperature of the cooling plate exceeds speci-
fied tolerance level. Excessive heat can also shorten the performance life of the
various AC drive components.
Manufacturer Type Model
Recommended
spread amount
Wacker Chemie
Silicon paste for heat
dissipation
P 12
100
μ
m
Apply the coating
evenly across the
surface
Fischer Elektronik WLPF
Silicon paste for heat
dissipation
WLPF
Table 5. Recommended cold plate thermal compound.