The DS200SDCIG1A is a Dc Power Supply and Instrumentation Board designed by General Electric (GE) Drive Systems for its DC2000 series DC drives. Belonging to the SDCI (Dc Power Supply and Instrumentation Board) series, this board is part of the G1 group and represents revision A. It is a critical component within the DC2000 DC drive system, responsible for power conversion, signal conditioning, and instrumentation measurement, and is suitable for drive applications with input voltages up to 600 V ac.
The primary function of the SDCI Dc Power Supply and Instrumentation Board is to convert input power from the control power transformer into the various logic power supplies required by the drive control system. Additionally, it provides motor field power circuits, armature SCR gating circuits, and measurement and conditioning of AC line and DC motor signals. This board integrates multiple functions, including power conversion, signal measurement, and gate driving, making it a core component for achieving precise control and reliable protection in DC2000 drive systems.
The G1 version of the SDCI board includes an internal field exciter rated at ≤10 A, making it suitable for small and medium DC drive applications. The primary difference between the G1 version and the G2 version (used with external exciters) lies in the configuration of the internal field excitation circuit. The DS200SDCIG1A board is designed to meet the demands of industrial drive applications and features the following characteristics:
Multiple Power Outputs: Provides +5 V dc (4 A), ±15 V dc (0.4 A each), ±24 V dc, and 115 V ac (0.4 A) logic power supplies.
Motor Field Power Circuit: Supplies power to the motor field (excluding the SCR module).
Armature SCR Gating Circuit: Drives the gate pulse transformers for the armature SCRs.
Comprehensive Signal Measurement: Measures armature current, armature voltage, field current, AC line current, AC line voltage magnitude, and phase sequence.
Configurable Hardware Jumpers: Supports configuration of various functions through hardware jumpers.
Comprehensive Protection Circuits: Multiple fuses with status indicators for convenient fault diagnostics.
This product is widely used in DC drive systems and industrial drive control applications, particularly in industrial environments requiring highly reliable power supplies and precise signal measurement.
II. Key Functions
1. Multiple Logic Power Outputs
The DS200SDCIG1A board converts input power from the control power transformer into multiple stable DC and AC outputs:
+5 V dc, 4 A: Provides core operating power for the main control board (SDCC) of the drive control system.
±15 V dc, 0.4 A each: Powers analog circuits and signal conditioning circuits.
±24 V dc: Provides power for relays and external loads.
115 V ac, 0.4 A: Provides AC power for external devices such as cabinet fans.
All power outputs are protected with overcurrent protection, and fuse status is indicated via LEDs or neon lamps.
2. Motor Field Power Circuit
The DS200SDCIG1A board includes a motor field power circuit (excluding the SCR module) that supplies excitation power to the field winding of the DC motor. The G1 version includes an internal field exciter rated at ≤10 A, suitable for small and medium drive applications. The field power circuit is protected by fuses FU5 and FU6, with neon lamps LT5 and LT6 indicating fuse status.
3. Armature SCR Gating Circuit
The DS200SDCIG1A board provides circuits to drive the gate pulse transformers for the armature SCRs. It interfaces with the main control board (SDCC) via the 1PL connector, receiving trigger signals from the SDCC and converting them into the power level required to drive the SCR gates.
4. Signal Measurement and Instrumentation Circuits
The DS200SDCIG1A board integrates multiple signal measurement circuits for monitoring drive system operating conditions:
Armature Current Measurement: Measures armature current via a shunt.
Armature Voltage Measurement: Measures armature voltage magnitude.
Field Current Measurement: Measures motor field current.
AC Line Current Measurement: Measures AC line current on phases L1 and L3 via AC current transformers (ACCTs).
AC Line Voltage Measurement: Measures AC line voltage magnitude and phase sequence.
These measurement signals are transmitted to the SDCC main control board via the 1PL connector for closed-loop control and protection functions.
5. MA Contactor Control Circuit
The DS200SDCIG1A board includes an MA AC contactor control circuit. Hardware jumper JP2 is used to configure the contactor dropout delay. During normal operation, this circuit delays the opening of the AC contactor to ensure that all load current has been extinguished. The JP2 jumper provides approximately 100 ms delay (normal operation) or minimum delay (manufacturing test).
6. MD Contactor Control Circuit
The DS200SDCIG1A board provides an MD contactor drive output. Hardware jumper JP1 is used to configure the control source for the MD contactor:
7. AC Line Current Transformer Interface
The DS200SDCIG1A board uses switch SW1 to select the burden resistance for the AC line current transformers, accommodating drive systems with different rated currents. The 16-position SW1 settings are selected based on the drive’s rated DC current and CT turns ratio, ensuring correct operation of the AC instantaneous overcurrent (IOC) protection function. When the main line ACCT secondary current exceeds 144 mA, the CTs are routed through 10:1 step-down CTs on the SHV/SHVM board.
III. Hardware Architecture
1. Board Structure
The DS200SDCIG1A board uses a standard printed circuit board structure and is installed in the drive control cabinet, located behind the SDCC main control board. The board includes:
Multiple Power Circuits: Provide +5 V, ±15 V, ±24 V dc and 115 V ac outputs.
Signal Measurement Circuits: For measuring armature current, voltage, field current, AC line current, and AC line voltage.
Gate Drive Circuits: Drive the armature SCR gate pulse transformers.
Protection Circuits: Multiple fuses (FU1-FU3, FU5, FU6).
Status Indicators: Neon lamps (LT1, LT5, LT6) and LEDs (CR51, CR55).
Configurable Components: Jumpers JP1, JP2 and switch SW1.
Multiple Connectors: 1PL, 2PL, 5PL, 1CPL, CNPL, CPTPL, FAPL, NPL, PPL, etc.
2. Mounting Location
The DS200SDCIG1A board is installed in the board carrier of the drive control cabinet, located behind the SDCC main control board. To replace the SDCI board, the SDCC board must be lifted forward to access the SDCI board.
3. Connector Description
The DS200SDCIG1A board includes various connectors for power, control signals, and measurement signals:
| Connector | Function Description |
| 1PL | I/O communication with the SDCC main control board |
| 2PL | Power input from the power supply board to the SDCI |
| 5PL | I/O with the PCCA Power Connect Card |
| 1CPL | AC current transformer input |
| CNPL | MA contactor control output |
| CPTPL | Control power transformer output |
| FAPL | Fan power output |
| NPL | N2 SCR cathode and gate connection |
| PPL | P1 SCR cathode and gate connection |
4. Fuses and Indicators
| Fuse | Function | Indicator |
| FU1 | 115 V ac power supply fuse, 1/2 A, 2AG | LT1 (neon lamp) |
| FU2 | +24 V, +15 V, +5 V power supply fuse, 7 A, 2AG | CR51 (red LED) |
| FU3 | -24 V, -15 V power supply fuse, 7 A, 2AG | CR55 (red LED) |
| FU5 | Internal NRX 10 A field and/or MOV assembly fuse, 15 A | LT5 (neon lamp) |
| FU6 | Internal NRX 10 A field and/or MOV assembly fuse, 15 A | LT6 (neon lamp) |
IV. Detailed Interface Description
1. Connector 1PL
The 1PL connector is the primary communication interface between the SDCI board and the SDCC main control board, transmitting:
Power status signals (DPSEN)
Phase current feedback signals (/IA, /IB, /IC)
Voltage feedback signals (V(B-A), V(C-A), VDC)
Line synchronization signal (LINESYN)
Gate drive enable signals (ENA, ENB, ENC)
Fault signals (FAULT1, FAULT2)
System reset signal (/RST1)
2. Connector 2PL
The 2PL connector provides power inputs from the power supply board to the SDCI, including:
/PSEN: power supply enable signal
±15 V dc, ±24 V dc, and +5 V dc power
DCOM: power supply common
3. Connector 5PL
The 5PL connector connects to the PCCA Power Connect Card, transmitting SCR gate pulse signals.
4. Connector 1CPL
The 1CPL connector connects to AC current transformers (ACCTs) on phases L1 and L3, bringing CT secondary current signals into the SDCI board.
5. Connectors CNPL, CPTPL, FAPL
These connectors interface with external devices:
6. Connectors NPL, PPL
These connectors interface with the SCR module gate and cathode:
V. Configuration and Settings
1. Hardware Jumper Configuration
The configurable hardware on the DS200SDCIG1A board includes two jumpers (JP1, JP2) and one DIP switch (SW1):
| Jumper/Switch | Function | Default Position | Description |
| JP1 | MD contactor control source | 1-2 (MD controlled by MCP software) | 2-3: MD hardware slaved to MA operation |
| JP2 | MA AC contactor dropout delay | 1-2 (normal operation, ~100 ms delay) | 2-3: minimum delay (manufacturing test) |
| SW1 | ACCT burden selection | Based on drive configuration | 16 positions corresponding to different CT secondary current ranges |
2. DIP Switch SW1 Settings
SW1 selects the burden resistance for the AC line current transformers. The setting is based on the drive’s rated DC current and CT turns ratio:
| Position | Switch State | CT Secondary Current Range (mA) |
| 0 | All off | 0.0 ≤ Ict < 6.1 |
| 1 | 1 on | 6.1 ≤ Ict < 13.4 |
| 2 | 2 on | 13.4 ≤ Ict < 21.1 |
| 3 | 1,2 on | 21.1 ≤ Ict < 28.4 |
| 4 | 3 on | 28.4 ≤ Ict < 39.3 |
| 5 | 1,3 on | 39.3 ≤ Ict < 46.7 |
| 6 | 2,3 on | 46.7 ≤ Ict < 54.4 |
| 7 | 1,2,3 on | 54.4 ≤ Ict < 61.8 |
| 8 | 4 on | 61.8 ≤ Ict < 88.7 |
| 9 | 1,4 on | 88.7 ≤ Ict < 96.0 |
| 10 | 2,4 on | 96.0 ≤ Ict < 103 |
| 11 | 1,2,4 on | 103 ≤ Ict < 111 |
| 12 | 3,4 on | 111 ≤ Ict < 122 |
| 13 | 1,3,4 on | 122 ≤ Ict < 129 |
| 14 | 2,3,4 on | 129 ≤ Ict < 137 |
| 15 | All on | 137 ≤ Ict < 144 |
3. Fuse Replacement Considerations
FU1: 115 V ac power supply fuse. If blown, check for wiring errors or overload. When blown and a load is connected, neon lamp LT1 illuminates.
FU2: +24 V, +15 V, +5 V power supply fuse. Commonly caused by accidental short of +24 V. If the fuse continues to blow with 1PL, 2PL, and 5PL disconnected, replace the SDCI board.
FU3: -24 V, -15 V power supply fuse. Commonly caused by accidental short of -24 V. If the fuse continues to blow with 1PL, 2PL, and 5PL disconnected, replace the SDCI board.
FU5/FU6: Internal NRX 10 A field and/or MOV assembly fuses. If blown, neon lamps LT5/LT6 illuminate. Possible causes include defective SDCI board, defective MOV assembly, defective field SCR package, or wiring short.
VI. Installation and Maintenance
1. Mounting Location
The DS200SDCIG1A board is installed in the board carrier of the drive control cabinet, located behind the SDCC main control board. To replace the SDCI board, the SDCC board must be lifted forward to access the SDCI board.
2. Replacement Procedure
Power Off: Turn off power to the drive, wait several minutes for power supply capacitors to discharge, and test to verify that no power exists.
Open Cabinet Door: Access the printed wiring board area, locating the front-facing SDCC board.
Lift SDCC Board: Pull the locks on either side of the cabinet, lift the SDCC board, and tilt it forward to expose the SDCI board.
Disconnect Cables: Carefully disconnect all cables. For ribbon cables, grasp the sides of the cable connector and gently pull; for cables with pull tabs, carefully pull the tab.
Release Snaps: Push back the plastic snaps to remove the old SDCI board.
Configure New Board: Set all configurable components (JP1, JP2, SW1) on the new board to the same positions as on the board being replaced.
Install New Board: Install the new SDCI board, ensuring all snaps snap into position.
Reconnect Cables: Reconnect all cables as labeled, ensuring they are properly seated at both ends.
Reset SDCC Board: Return the SDCC board to its position and secure the locks.
3. Maintenance Recommendations
ESD Precautions: Always wear a grounding strap when handling boards. Store boards in anti-static bags.
Periodic Inspection: Check connectors for looseness and fuse status indicators for proper operation.
Spare Parts Management: It is recommended to keep at least one identical SDCI board on-site as a spare to minimize downtime.
Fuse Inspection: Regularly check the status of all fuses; if any are blown, promptly investigate the cause.
VII. Applications
The DS200SDCIG1A Dc Power Supply and Instrumentation Board is widely used in the following industrial applications:
DC2000 DC Drive Systems: Provides power conversion and signal measurement functions for DC motor drives.
Small and Medium DC Drives: The G1 version includes an internal field exciter ≤10 A, suitable for small and medium DC drive applications.
Industrial Process Control: Provides control power and feedback measurement in industrial processes requiring DC motor drives.
System Upgrades and Retrofit Projects: Replaces power supply and instrumentation boards in older drive systems, enhancing system reliability.
