Answer / kunal

Motors are generally cooled by three methods :
1. naturally ventilated: no special ventilation cooling by
natural conduction and radiation.
2. blower ventilated:
separate blower, with small external motor and filter
provided. which allows motor to accept additional external
air and force heated air out
3. separately ventilated motor:
separately ventilated by ducted air flow through the enclosure
more information can be found at
http://www.globalspec.com/reference/10786/179909/Chapter-3-AC-and-DC-Motors-DC-Motors-Enclosure-Types-and-Cooling-Methods

Answer / logu

motor top side extra readiator unit fixed and inlet cold
water circulation. water upserve the hot air...then reduced
the motr windng temp .

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