GE AF-650 GP Design Manual page 113

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 6.24: Unit Size 4X Derating vs. Pressure Change
Drive air flow: 450 cfm (765 m
6
Illustration 6.25: Unit Size 5X Derating vs. Pressure Change (Small Fan), 350 HP @ 460V and 500-550 HP @ 690 V
Drive air flow: 650 cfm (1105 m
Illustration 6.26: Unit Size 5X Derating vs. Pressure Change (Large Fan)
Drive air flow: 850 cfm (1445 m
Illustration 6.27: Unit Size 61, 62, 63 and 64 Derating vs. Pressure Change
Drive air flow: 580 cfm (985 m
112
3 /h)
3
/h)
3 /h)
3 /h)
AF-650 GP Design Guide