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Cooling (IEC 60 034-6)

Motors of frame size 56 have no cooling-fan (IC 410). Cooling is maintained by free convection.Motors of frame sizes 63 to 355 are surface cooled by means of an external radial flow cooling-fan (IC 411)which is protected by a steel sheet cowl with standard test-finger proof openings for sufficient air flow. The
cooling-fan is fixed onto the non-drive end of the motor shaft and operates independent of the direction of rotation.The cooling-fans are injection mould high grade polyamide.