Siemens SINAMICS G120 - Power Losses and Air Cooling Requirements

Installing
3.3 Power losses and air cooling requirements
Power Module PM240-2
28 Hardware Installation Manual, 01/2020, A5E33294624B AL
3.3 Power losses and air cooling requirements
Cooling requirements
To protect the components from overheating, the control cabinet requires a cooling air flow,
which depends on the power loss of the individual components.
Formula for calculating the cooling airflow:
airflow [l/s] = power loss [W] * 0.86 / ΔT [K]
•
Power loss:
Total of the power losses of the individual components.
•
Δ T:
Permissible temperature rise i
n the control cabinet
Measures in order to ensure that the components are adequately cooled
•
Add the power losses of the
individual components.
– Power Module data:
"Technical data (Page 73)".
– The Control Unit power loss is
less than 0.04 kW.
– Use the manufacturers data for
components, for example
reactors or filters
•
Calculate the air flow required,
using the formula above.
•
Ensure that the control cabinet is
appropriately ventilated and
equipped with suitable air filters.
•
Ensure that the components
maintain the specified clearances
with respect to one another.
•
Ensure that the components are provided with adequate cooling air through the cooling
openings.
•
Use the appropriate air barriers to prevent cooling air short circuits
Power loss for Power Modules with push-through technology - PT devices
When you use PT Power Modules, the majority of the power loss is dissipated through the
heatsink located outside the control cabinet.