Rockwell Automation 7000A PowerFlex Medium Voltage AC Drive (A Frame) - ForGe Control (PanelView 550) - Manual (Page 158)

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Component Definition and Maintenance
7000A-UM151D-EN-P – March 2013 7000 “A” Frame
1. Record the distance from the end of the motor shaft to the bushing.
The new impeller must be installed in the same location. Failure to do
so will result in gaps between the impeller and the intake ring
resulting in loss of air flow, or rubbing of the impeller against the inlet
ring or motor assembly during operation.
2. Remove both cap screws from the bushing. The impeller or bushing
may fall as screws are loosened.
3. Thread the cap screws by hand into the two threaded holes in the
bushing flange.
4. Tighten each bolt part of a turn successively, to push the impeller off
the bushing. Screwing down the cap screws into these holes will
force the bushing away from the impeller hub, releasing the
compression on the shaft. Be careful that the impeller does not fall as
the clamping force is released.
5. Pull the bushing off the shaft and remove the impeller. If the
assembly has been in place for some time, it may be necessary to use
a wheel puller to remove the bushing. Never use a wheel puller on
the impeller.
NOTE: DO NOT LUBRICATE CAPSCREWS, BORE, OR
BUSHING BARREL, AS THIS WILL HINDER CLAMPING
FORCE OF THE BUSHING ON THE SHAFT AND THE
IMPELLER BORE
Installation of Impeller Assembly onto Motor Shaft
The fan impeller is held onto the motor shaft with a split tapered bushing.
This bushing is positioned on the motor shaft and through the center of
the impeller. Cap screws, when tightened to 10.2 N-m (7.5 ft-lbs.), lock
the bushing onto the motor shaft and the impeller to the bushing.
The bushing barrel and the bore of the impeller are tapered which assures
concentric mounting and keeps the impeller running evenly.
The cap screws, when tightened, lock the bushing in the impeller and over
the motor shaft.
The bushing is split down the middle, so that when the locking cap screws
force the bushing into the tapered bore in the impeller assembly, the
bushing will grip the shaft with a positive clamping fit.
The impeller and bushing assembly have keyways that line up with the
shaft and are held in place with compression.
Impeller Maintenance
(DC Link / Fan Section)
(cont.)