Application Notes - BONFIGLIOLI active Installation Manual

5

Application notes

Note the operating diagrams for power reductions (derating) in the instructions.
-
The temperature of the cold plates of the frequency inverters must not exceed
-
T
kmax
power of 4.0...18.5 kW.
Additional power losses P
-
cabinet. These losses may amount to 30% of the total energy dissipation and must
be considered in the calculation of the volume of the control cabinet. The values
are listed in the tables in chapter "Thermal resistance".
If several frequency inverters or other heat-producing devices are mounted on a
-
common heat sink (sum cooler), the losses of all devices must be added up. Calcu-
late the max. permissible thermal resistance R
mal resistance").
The contact surface of the heat sink must at least be as large as the contact sur-
-
face of the cold plate of the frequency inverter.
The contact surfaces of the heat sink and the cold plate of the frequency inverter
-
must be plane.
Black anodized heat sinks are particularly suitable. If free convection is guaran-
-
teed, these heat sinks have a thermal resistance which is 5...10% lower than that
of untreated heat sinks.
14
= 75 °C for a nominal power of 0.55...3.0 kW and T
v int
are dissipated as heat into the interior of a control
using the formula (chapter "Ther-
th
= 70 °C for a nominal
kmax
11/06