GE Industrial Solutions AF-650 GP General Purpose Drive (460_575_690V 125HP and above) - Manual (Page 39)

External ducts
If additional duct work is added externally to the Rittal cabinet the pressure drop in the ducting must be calculated. Use the charts below to derate the frequency
converter according to the pressure drop.
Illustration 3.32: Unit Size 4X Derating vs. Pressure Change
Drive air flow: 450 cfm (765 m3/h)
Illustration 3.33: Unit Size 5X Derating vs. Pressure Change (Small Fan)
Drive air flow: 650 cfm (1105 m3/h)
Illustration 3.34: Unit Size 5X Derating vs. Pressure Change (Large Fan)
Drive air flow: 850 cfm (1445 m3/h)
AF-650 GP High Power Operating Instructions
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