Illustration 1 | g01277292 |
Controls Cabinet Left Panel (17) Breaker and Contactor Status Board (18) Remote EPO Terminal Block (19) T8 Modem Power Transformer (20) T6 Transformer (21) General Purpose Interface Board (22) Fan Power Fuse Block (23) Fuses F29-F32 (24) Fuses F20-F22 (25) Fuses F25-F28 (26) EPO Reset (27) Neutral Distribution Terminal (28) K1 Motor Power Relay (K9) |
Multidrop Bus
The General Purpose Interface Board provides serial data over the UPS 1200 Multidrop Bus. The General Purpose Interface Board functions as a slave on this bus, receiving commands from the APC-2 and responding with status information.
The General Purpose Interface Board has a jumper-selectable 100-Ohm terminating resistor for the Multidrop bus. Jumper "JMP9" provides terminal resistance. There is also a switch that sets the Node ID. Set the General Purpose Interface Board Node ID and terminating resistor jumper to the settings on the following table.
Controls GPI Settings     | |
---|---|
Node ID     | 1     |
Terminating Resistor     | JMP9 - Never installed     |
Refer to Systems Operation, Testing and Adjusting, RENR7654, "Multidrop Network - Setup" for information on setting up the Multidrop Network.
Fan Tachometers
The General Purpose Interface Board provides circuitry to read magnetic tachometer signals for the three fans in the Controls Cabinet. Sensors in each fan provide once-per-revolution digital pulses to the General Purpose Interface Board. These pulses are digitized by the General Purpose Interface Board and relayed to the APC-2 in the Controls Cabinet.
Temperature Measurement
The General Purpose Interface Board provides the system with temperature measurements from an on-board thermistor (R37) that measures the temperature near the General Purpose Interface Board and a remotely located thermistor that measures the DC power supply temperature. The General Purpose Interface Board digitizes temperature information and makes the data available to the APC-2.
There is also a thermistor connected to connector "J11" that measures the temperature of the Filter Inductor.
General Purpose Inputs
The General Purpose Interface Board monitors the status of the following components:
- Two DC Power Supply Boards
- Two sets of AC Filter Fuses
Status signals for the components are received via the General Purpose inputs on the General Purpose Interface Board. The status signals are then digitized and sent to the APC-2 board in the Controls Cabinet.
LED Indicators
Controls General Purpose Interface Board LED Indicators     | ||
---|---|---|
LED     | Board Designation     | Purpose     |
0     | D0     | Filter Fuse 1     |
1     | D1     | Filter Fuse 2     |
2     | D2     | Power Supply 1     |
3     | D3     | Power Supply 2     |
    | D14     | Datalock with APC     |
Controls General Purpose Interface Board Diagram
Illustration 2 | g01277775 |
Removal
- Perform steps in the Systems Operation, Testing and Adjusting, "Internal Component Preremoval Steps (Controls Cabinet)" in order to de-energize the system and gain access to internal components.
- Disconnect all connectors from the board. The connectors locations in the unit are labeled. Verify each connector to make sure that the label is present and legible.
Refer to Illustration 2.
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. |
- Unscrew the cross head screw from the lower right corner of the board.
- Disconnect the seven white plastic stand-offs connecting the board to the right panel using the following method.
Note: The board must be removed from the stand-offs without bending the board.
- Pinch the head of each stand-off so that the board is not locked to the stand-off but is still attached to the stand-off.
- Remove the board by gently and evenly pulling the board from all stand-offs at the same time.
Installation
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. |
- Position the board in the cabinet over the seven white stand-offs that are connected to the right panel.
- Push the board, gently and evenly, onto all the stand-offs simultaneously. Make sure all stand-offs are locked in place.
- Insert the cross head screw in the lower right corner of the board. Tighten the screw into the right panel.
- Plug the wire connectors into the correct connectors on the board. Check the labels on each connector for proper placement.
Refer to Illustration 2.