Usage:
Problem:
The droop modules are incorrectly assembled on ALL 3500 SR4B generators that contain a VR3 voltage regulator. Problems could occur due to an incorrectly assembled droop module. The problems include improper parallel operations using the voltage droop method. This problem occurs because, in the current orientation of the 173-7793 Droop Module, the wiper that adjust the impedance between terminal blocks 5 and 6 is located across the bottom of the 170-5400 Main Terminal Strip Assembly. These wires terminate at the droop current transformer. However, the wiper should be adjusting the impedance across the top of the strip, where the wires terminate on the VR3 voltage regulator.
Solution:
- 1. Remove the 173-7793 Droop Module.
- 2. Remove the wires labeled 5 and 6 from the top and bottom row of the 170-5400 Main Terminal Strip Assembly. See Illustration 1 (INCORRECT ASSEMBLY).
- 3. Remove the end block.
- 4. Remove terminal blocks 5 and 6 along with the divider. Rotate the terminal blocks and divider 180 degrees. Terminal block labels 5 and 6 should remain on their original terminal blocks.
- 5. See Illustration 2 (CORRECT ASSEMBLY). Install the terminal blocks on the rail in their new location.
- 6. Install and tighten the end block.
- 7. Install both sets of wires 5 and 6 into their respective terminal blocks.
- 8. Install the droop module into terminal blocks 5 and 6.
Illustration 1. (INCORRECT ASSEMBLY)
Illustration 2. (CORRECT ASSEMBLY)
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