Thermal Behaviour Of The Complete System - Lenze 9350 Series Operating Instructions Manual

5 Mechanical installation
Mounting in cold−plate design

Thermal behaviour of the complete system

5.4.3 Thermal behaviour of the complete system
The thermal conditions within a system are affected by some basic conditions.
The following items have to be taken into consideration when a control cabinet
or system is designed:
Ambient temperature of the controllers
For the ambient temperature of the braking unit, furthermore the rated data
and the corresponding derating factors at increased temperature apply.
Heat generation in the interior of control cabinets
In addition to the device losses that are dissipated via the heatsink, further
losses have to be taken into consideration for the design:
Losses within the braking unit
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–
These losses are caused by the electronic supply, fans, DC−bus
capacitors, etc.
Losses of the components on the mains and motor side
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Radiation of heat from the external cooling unit into the interior
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–
This portion of the heat energy for instance depends on the type of
cooling unit and the mounting mode.
Heat distribution on the collective cooler / within the control cabinet
If you mount several components (controllers, braking units, etc.) onto a
common cooler, it has to be ensured that the temperature on the cooling plate
of each individual component does not exceed 75 _C.
Measures:
Observe minimum clearances around the convection cooler.
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Do not mount the components on top of each other.
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In order to avoid heat concentrations within the control cabinet, use
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internal fans, if required.
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EDBMB935X DE/EN/FR 11.0