The External Source Sync Board is used to measure output voltage and current. The External Source Sync Board also has an additional voltage feedback for the External Source Sync Option.
The primary function of the External Source Sync Board is to monitor the following signals:
- the AC voltages from the external source
- the AC output voltages of the UPS
- the output currents of the UPS
Each of these channels are digitally sampled and the resulting data is processed by the on-board Field Programmable Gate Array.
The External Source Sync Board communicates with the All Purpose Controller 2 (APC2) through the multi-drop network. The APC2 Board is located in the Controls cabinet.
The APC2 receives the real-time readings from the External Source Sync Board. The calibration factors of the channels of the External Source Sync Board are stored in the on-board serial flash. The calibration factors of the channels of the External Source Sync Board are programmed, then the calibration factors of the channels of the External Source Sync Board are read back by the APC2 through the multi-drop network.
The Customer Connections Terminal Block for the External Source Sync Board is accessed from the 4-Wire Output cabinet that is located to the left of the 4-Wire Transformer cabinet. The external sync signal for the customer is wired at this location.
Multidrop Bus
The External Source Sync Board provides serial data over the Multidrop Bus. The External Source Sync Board functions as a slave on this bus, receiving commands from the APC2 and responding with status information.
The External Source Sync Board has a 100 ohm terminating resistor that is selected by the use of a jumper. Jumper "JMP4" (18) provides the terminal resistance. Set Jumper "JMP4" (18) on the External Source Sync Board to the settings on the following table.
| Multidrop Settings (External Source Sync Board) | |
|---|---|
| Node ID | Fixed at 7 |
| Terminating Resistor "JMP4" | Version 1 Hardware - Never installed |
| Version 2 Hardware - Always installed | |
Refer to Systems Operation, Testing and Adjusting, RENR7654, "Multidrop Network - Setup" for information on setting up the Multidrop Network.
External Source Sync Option
 | |
| Illustration 1 | g01327128 |
4-Wire Transformer Cabinet Fan Plenum Panel - Version 1 (1) General Purpose Interface Board (GPI) (2) External Source Sync Board (3) 4-Wire Thermal Switch Monitor Board (4) Fuses F96, F97 (5) Secondary Current Transformers (6) Fuses F58-F60 F61-F63 (7) Fuses F73-F76, F94, F95 | |
 | |
| Illustration 2 | g01327129 |
4-Wire Transformer Cabinet Upper Panel - Version 2 Hardware (1) General Purpose Interface Board (GPI) (2) External Source Sync Board (3) 4-Wire Thermal Switch Monitor Board (4) Fuses F96, F97 (5) Secondary Current Transformers (8) Fuses F61-F63 F103 (9) Fuses F73-F76, F94, F95, F104,105 (10) Fuses F64-F66 | |
The External Source Sync Option is a purchased option that allows the UPS output voltage to be synced to an external signal when the UPS is in discharge. If the UPS is not in discharge, the External Source Sync function will not be in effect.
In addition to being in discharge, the External Source Sync command on the terminal block of the External Source Sync Board must be active for the UPS output to be synchronized to the external signal.
Fuses
The fuses for the External Source Sync Board (17) are indicated in Table 2. Visually inspect the fuse. Replace the fuse if the fuse is blown.
| Fuses (External Source Sync Board) | |
|---|---|
| Fuse | Type |
| ESS-F2 (16) | 250VAC 1A Fast |
| ESS-F3 (17) | 250VAC 1A Fast |
Calibrations
When this board is replaced, the following calibrations need performed:
- Systems Operation, Testing and Adjusting, RENR7654, "4 Wire Out Voltage - Calibrate"
- Systems Operation, Testing and Adjusting, RENR7654, "4 Wire Output Current - Calibrate"
Removal
- Perform steps in the Systems Operation, Testing and Adjusting, "Internal Component Preremoval Steps (4 Wire Transformer 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 3.
| 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 tip ground screw from the upper left corner of the Board.
- Disconnect the seven white plastic stand-offs connecting the board to the left 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 left 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 tip ground screw in the upper left corner of the board and screw the ground into the fan plenum shield panel.
- Plug the wire connectors into the correct connectors on the board. Check the labels on each connector for proper placement.
Refer to Illustration 3.
- Refer to the information that is listed in Step 5.a through Step 5.a in order to Calibrate the External Source Sync.
- Perform the Systems Operation, Testing and Adjusting, RENR7654, "4 Wire Out Voltage - Calibrate" procedure.
- Perform the Systems Operation, Testing and Adjusting, RENR7654, "4 Wire Output Current - Calibrate" procedure.
 | |
| Illustration 3 | g01272571 |