Left Panel Components
The Breaker and Contactor Status Board (306) is the primary means of controlling and monitoring the state of the input and output circuit breakers as well as the K3 and K4 inverter contactors inside the lower Controls cabinet plenum and the K6 and K7 precharge contactors located on the rear panel of the Controls cabinet.
The 230/115VAC transformer for modem power (option) is powered from the output of the UPS and converts AC voltage to the appropriate level for operating the modem (optional) located in the upper Controls cabinet customer tray.
The T7 multitap transformer that is mounted on the left panel receives input power from UPS protected output and provides AC power to the fans.
The EPO circuit reset button enables the system to start operation after an operator uses the EPO for emergency power down of the UPS.
The General Purpose Interface Board monitors the analog temperature values of the filter inductors and measures the tachometer feedback from each fan to insure proper operation. The General Purpose Interface Board also monitors the status of the AC filter fuses through digital switch inputs.
Rear Panel Components
The rear panel of the Controls cabinet contains the DC bus pre-charge circuit for the UPS. The pre-charge circuit allows the system to charge the DC bus prior to operating in line-interactive mode. The UPS input is connected to a contactor which enables the circuit. This contactor is followed in series by the load resistors. These resistors limit the in-rush current.
Once the system reaches a nominal value as measured by the DC measurement circuit in the High Voltage Interface Board, the second contactor bypasses the load resistors and boosts the voltage close to full operating levels. A Zig-Zag transformer is in this circuit that ensures balanced voltage is applied to the DC bus at the appropriate level and is connected to the neutral point on the inverter DC bus.
The 24 V unregulated DC power supplies are operated by a step-down transformer, an AC rectifier, and DC filter capacitors. Four transformers and two boards act as independent and redundant DC power supply sources. Two of the transformers are connected to the UPS inputs and two transformers are connected to the UPS protected output. Each transformer is connected to different phases on both input and output to prevent loss of power if a single phase is low or inoperable. The fuses in the circuit prevent over-current conditions on the transformer inputs and the Power Supply Boards contains fuses on the 24V DC output to protect from short circuits on the DC side.
Fuses are provided in the pre-charge circuit to protect circuit components and the capacitors on the system DC bus. The 3-phase input is rectified by a diode bridge in the Inverter cabinet to create a DC voltage.
Right Panel Components
The right panel contains six Input and Output Secondary Current Transformers (CTs) for UPS input and output current measurement scaling. The inputs of these CTs are connected to the primary CTs in the Static Switch Cabinet. The outputs of these CTs are connected to the analog inputs of the High Voltage Interface Board that is mounted on the same panel.
The APC2 Board provides a central hub for digital control. The APC2 Board provides the hardware platform necessary to support system control algorithms, including program execution and storage, and communication ports to interface to other system boards.
The Dual Network Interface Board provides an isolated DC power supply interface to support cabinet to cabinet communication with UPSNet and CSNet. UPSNet is used in Series 1200 paralleled systems and in both cases there are primary and redundant network communication with the CSHVs. In addition, two RS-232/RS-485 ports are provided.
The High Voltage Interface Board monitors input and output AC currents and voltages and DC Bus voltages. Each of these channels will be digitally sampled and the resulting data sent serially to the APC2 Board. The HVI will also receive a serial data stream from the APC2. The calibration factors (offsets and gains) of the HVI channels are stored in the on-board EEPROM. They are programmed and read back by the APC2 through the serial data links.
Lower Plenum Components
The lower plenum contains AC filter components and the K3 and K4 inverter contactors which connect the 3-phase voltage regulation portion of the system to the UPS output. Bus bars in this plenum connect the contactors to the output node of the line inductor in the Static Switch Cabinet. The AC filter node is a combination of AC capacitors and filter inductors. The six inductors are laminated steel with copper windings and are mounted inside the plenum for cooling. The AC filter caps are mounted on top of the plenum where cooling vents from the pressurized plenum provides cooling to the capacitor bodies. All cooling is provided by three fans.
Graphical User Interface
The Graphical User Interface is mounted on a panel inside the Controls cabinet front door. This interface consists of the Graphics Master Board, the Display Interface Board, the 264.2 mm (10.4 inch) flat panel touchscreen and the backlight inverter.
The Graphics Master Board is a Strong-ARM RISC-based processor board that reads telemetry data and system status information from the APC2 and formats the data for display on the flat panel touchscreen. This board also monitors the status of the touchscreen on the display for operation actions and requests for changing display content. The graphics master also provides an optional customer RS-232 ethernet interface and external RS-485 communications.
The Display Interface Board has an isolated 12V supply and an isolated 5V supply that supplies power the graphics master. Input power is from the unregulated 24V supply on "J1". The output of the 5V and 12V isolated supplies are on "J3".
The backlight inverter is a small circuit board for high voltage/low-current power supply to operate the display backlighting fluorescent tubes mounted within the Flat panel touchscreen. The 264.2 mm (10.4 inch) flat-panel display with resistive touchscreen is an active matrix TFT-type of color display. The screen is covered by a glass panel and a 4-wire polymer-based resistive touchscreen for operator interface of buttons and control functions.
Also mounted to the bezel for the Graphical User Interface is the System Emergency Power Off Switch. This switch immediately shuts down all system operation.
Customer Interface Tray
The Customer Interface Tray is mounted on the top front of the Controls cabinet.
Included in the tray is an industrial 56k baud modem (optional), customer dry contacts, an RJ- 45 connector, and an RS-485 terminal block connector for external communication.
The communication interface in the tray is mounted to be accessible from the outside of the UPS without opening cabinet doors.
Inside the cabinet the Customer Contacts Interface Board monitors the dry contacts for customer functions.
Cabinet Diagrams
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| Illustration 1 | g01277287 |
Controls Cabinet - Left View (1) Customer Interface Tray (2) Clear Shield over Rear Panel (3) AC Filter Capacitors (4) Filter Inductors (5) Fans (6) Left Panel | |
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| Illustration 2 | g01277289 |
Controls Cabinet - Right View (1) Customer Interface Tray (2) Clear Shield over Rear Panel (3) AC Filter Capacitors (4) Filter Inductors (5) Fans (7) Right Panel (8) Parallel Service Switch (Parallel Systems Only) (9) Right Fan Tray (10) Front Plenum Gusset (11) Right Fan Plenum (12) Left Fan Plenum over K3 and K4 Inverter Contactors | |
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| Illustration 3 | g01277290 |
Controls Cabinet without Plenums (1) Customer Interface Tray (3) AC Filter Capacitors (4) Filter Inductors (7) Right Panel (8) Parallel Service Switch (Parallel Systems Only) (14) Rear Panel (15) K4 Inverter Contactor (16) K3 Inverter Contactor | |
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| Illustration 4 | 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) | |
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| Illustration 5 | g01277295 |
Controls Cabinet Back Panel (29) Customer Contacts Interface Board #2 (Optional) (30) DC Bus Pre-charge Circuit Resistors (31) T1 - T4 Transformers (32) Power Supply Board (PWS) (33) Customer Contacts Interface Board #1 (34) Power Supply Board (PWS) (35) Thermistor (36) Fuse F69 (37) Fuses F88-F90 F70-F72 (38) Zig-Zag Transformer (39) K7 Pre-charge Contactor (40) K6 Pre-charge Contactor | |
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| Illustration 6 | g01277298 |
Controls Cabinet Right Panel (41) CSNET Dual Network Interface Board (42) Wire Terminal Block (43) UPSNET Dual Network Interface Board (Optional) (44) APC2 Control Interface Board (45) Secondary Current Transformers (46) High Voltage Interface Board | |
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| Illustration 7 | g01277303 |
Customer Contacts Interface Tray Components (47) Modem Power AC-DC Transformer (48) Modem (49) Customer Contacts Interface Block 2 (Optional) (50) Customer Contacts Interface Block 1 (51) RJ-45 and RS-449 Connectors | |