Mitsubishi Electric FR-F740 EC Instruction Manual page 36

Enclosure design
Arrangement of multiple inverters
When multiple inverters are placed in the same enclosure, generally arrange them horizontally
as shown in the figure (a). When it is inevitable to arrange them vertically to minimize space, take
such measures as to provide guides since heat from the bottom inverters can increase the tem-
peratures in the top inverters, causing inverter failures.
Fig. 2-11: Arrangement of multiple inverters
NOTE When mounting multiple inverters, fully take caution not to make the ambient temperature of
the inverter higher than the permissible value by providing ventilation and increasing the
enclosure size.
Placement of ventilation fan and inverter
Heat generated in the inverter is blown up from the bottom of the unit as warm air by the cooling
fan. When installing a ventilation fan for that heat, determine the place of ventilation fan instal-
lation after fully considering an air flow. (Air passes through areas of low resistance. Make an air-
way and airflow plates to expose the inverter to cool air.)
Fig. 2-12: Placement of ventilation fan and inverter
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Inverter Inverter
Enclosure
a) Horizontal arrangement
Inverter
Good example!
Inverter Inverter
Guide
Guide
Inverter Inverter
Enclosure
b) Vertical arrangement
Inverter
Bad example!
Installation
Guide
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