Description
The Optical Rotor Position Sensor Assembly (RPS) is mounted to the upper bearing. The upper bearing is located on the top of each of the flywheel assembly. The Optical RPS Assembly is made up of the following components:
- Comm/Accel Fiber Optic board (CAF)
- RPS fiber optic cable
- Comm/Accel LED board
The Comm/Accel Fiber Optic board interfaces to the following boards:
- Comm/Accel LED board
- Flywheel Interface board
The Comm/Accel Fiber Optic board has two accelerometers that measure the horizontal and vertical vibrations. The measurements for vibrations are sent to the Flywheel Interface board.
The Rotor Position Sensor detects rotation of the rotor. The Rotor Position Sensor consists of a coupled light beam that is interrupted by a slotted rotor.
The Comm/Accel LED board provides the light source that is picked up by the rotor position sensor.
The Comm/Accel Fiber Optic board converts the light signal to an electrical signal. The electrical signal is transmitted to the Flywheel Interface board.
Removal Procedure
Refer to Systems Operation, Testing and Adjusting, RENR7654, "Internal Component Preremoval Steps (Flywheel Cabinet)" in order to shut down the system and gain access to internal components.
| NOTICE |
|---|
Electrostatic discharge can damage integrated circuits or semiconductors if you touch bus connector pins. When not in use, keep the module in the static-shield bag. Follow these guidelines when you handle any module: Touch a grounded object to discharge static potential. Wear an approved wrist-strap grounding device. Do not touch the bus connector or connector pins. Do not touch circuit components inside the module. If available, use a static-safe work station. |
- Remove the SAE O-ring plug in order to relieve the vacuum in the flywheel housing.
- Clean the SAE O-ring plug and threads. Apply a small amount of 6V-2055 Grease to the O-rings.
- Replace the SAE O-ring plug. Tighten the SAE O-ring plug to appropriate specifications.
- Disconnect the "J3" ribbon cable (3) from the "Com/Accel Fiber Optic" board (2). Refer to Illustration 1.
 | |
| Illustration 1 | g01278291 |
"Optical RPS" Assembly (1) "RPS Fiber Optic" Cable (2) "Comm\Accel Fiber Optic" Board (3) "J3" Ribbon Cable (4) O-Ring Groove (5) "Comm\Accel LED" Board (6) "FO" Cable Bracket (7) "RPS" Base Plate (8) O-Ring | |
- Remove the three mounting bolts (9) that hold the Rotor Position Sensor Assembly to the upper bearing. Use a 7/64 inch hex key to remove the bolts (9). Refer to Illustration 2 for the location of the bolts (9) .
 | |
| Illustration 2 | g01287467 |
Placement for the Rotor Position Sensor (9) Bolt | |
- Lift the Rotor Position Sensor straight up.
Installation Procedure
| NOTICE |
|---|
Electrostatic discharge can damage integrated circuits or semiconductors if you touch bus connector pins. When not in use, keep the module in the static-shield bag. Follow these guidelines when you handle any module: Touch a grounded object to discharge static potential. Wear an approved wrist-strap grounding device. Do not touch the bus connector or connector pins. Do not touch circuit components inside the module. If available, use a static-safe work station. |
- Install the O-ring on the base plate of the rotor position sensor.
- Position the Rotor Position Sensor Assembly in the cabinet over the upper bearing.
- Lower the assembly downward on top of the bearing. The bearing will sit in the circular groove with the "Comm/Accel LED" board and the bracket for the "FO" cable on either side of the gear in the bearing. Refer to Illustration 3.
 | |
| Illustration 3 | g01287510 |
Placement of the RPS Sensor | |
- Install the Rotor Position Sensor Assembly to the bearing with the three bolts. Use a 7/64 hex key to install the bolts. Tighten the bolts evenly. Refer to Illustration 2 for the location of the bolts.
- Connect the "J3" ribbon cable (3) to the Comm/Accel Fiber Optic board (2). Refer to Illustration 1.
- Perform calibration of the Rotor Position Sensor. Refer to Systems Operation, Testing and Adjusting, RENR9988, "RPS Postion Sensor - Calibrate".