______________________________________________
HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
170
Figure 7-5 Test Setup
7.7.2 Back Door Fan
Three phase back door motors have sealed ball bearings that require no routine
lubrication. A normal failure is the bearing seals, that allow lubrication to leak out. Any
sign of oil leakage indicates that the motor should be replaced or rebuilt with new
bearings.
Inspect fan blades for any sign of fatigue from excessive flexing causing cracking
where the aluminum blades are riveted to the hub. When removing blades the use of a fan
hub puller is recommended.
464-0370-000
hub puller for fan blade.
7.7.3 Check for Loose Connections
WARNING:
DISCONNECT ALL POWER TO PA CABINET BEFORE CHECKING CONNECTIONS