Usage:
SR4 Generators With 580 And 680 Frame Sizes
Reference: Service Magazine; August 6, 1990; Page 19; "Rotor Shaft Length Changed" For SR4 Generators With 580 And 680 Frame Sizes.
Reference: This article supersedes the reference article. Information regarding the 582 and 584 frame sizes is now available and is included in this article.
Description of Change: The 580 and 680 frame sizes of SR 4 Generators have two different lengths of main rotor shafts. A change to improve the heat sink assembly resulted in a longer main rotor shaft. However, a change in part number identifying the longer shaft did not coincide with the change in length.
Adaptable To: The change to the longer main shaft is effective with the Serial Numbers as listed in Chart A.
This change in shaft length affects the servicability of the excitor rotor and heat sink assembly for generators manufactured prior to the serial number listed in the chart. If these units experience a main rotor failure they may be serviced in the following manner.
When the short main rotor shaft is replaced with the longer shaft, a new heat sink and exciter rotor are needed. In addition to main rotor assembly (7), the following hardware is required:
- 1 - 9Y5976 Spacer (Inner) (1).
- 1 - 5N5003 Spacer (Outer) (2).
- 4 - 0S1591 Bolt (3).
- 1 - 7E6560 Heat Sink Assembly (4).
- 1 - 7E6561 Sleeve (5).
- 1 - 7E6557 Exciter Rotor (6) for frame sizes: 582 and 584.
- 1 - 7E7072 Exciter Rotor (6) for frame sizes: 589, 681, 685, 687 and 689.
- 1 - 5N5003 Spacer (Outer) (2).
Serviceability for other components on units manufactured prior to the serial numbers (short shaft) may be found in the Service Manual.
Location of components.