GE IS200RAPAG1B Rack Power Supply Board

The IS200RAPAG1B is a Rack Power Supply Board designed by General Electric (GE) for its Innovation Series Control System. This board is an important hardware revision within the RAPA series, primarily responsible for converting the input 48 V 25 kHz square wave power into various DC control voltages required by other boards in the rack, and providing system "Power ON" and "Master RESET" functions. Compared to the earlier G1A version, the G1B version offers enhanced output current capability, supporting higher power loads.

The IS200RAPAG1B board plugs into the Innovation Series board rack via the P1 backplane connector, providing the following DC output voltages to other boards in the rack:

• ±5 V dc (Digital circuits)

• ±15 V dc (Analog circuits)

• ±18-24 V dc (Unregulated bulk power)

• ±12 V dc (Isolated)

• +24 V dc (Isolated)

The board also integrates a reset function, providing undervoltage reset protection and master reset control via the PSEN line. During normal power-up, the PSEN line is held low for 100 milliseconds after the input to the 5 V regulator exceeds 9 V dc and the 5 V output exceeds 4.6 V dc. During power-down or a voltage dip, PSEN is asserted low when the 5 V regulator input drops below 9 V dc. Pressing the master reset button on the front panel also pulls PSEN low, and it remains low for 100 milliseconds after the button is released.

The IS200RAPAG1B board also includes a serial 1024-bit memory device, pre-programmed with board identification and revision information, accessible via the BRDID data line on the P1 connector. The front panel features two LED indicators (MPOK and IPOK) and four test points for diagnostic information. Additionally, the board includes a 1 A, 250 V fuse (FU1) for protecting the isolated 24 V power supply.

II. Main Functions

The primary functions of the IS200RAPAG1B include, but are not limited to, the following:

1. Power Conversion and Distribution

The IS200RAPAG1B board accepts a 48 V 25 kHz square wave input and converts it into multiple DC output voltages via internal circuitry, distributing them to other boards in the rack through the P1 connector. These voltages include:

• +5 V dc (Digital): Powers digital circuits, max load 7.0 A, regulated ±5%

• ±15 V dc (Analog): Powers analog circuits, max load 1.0 A, regulated ±5%

• ±18-24 V dc (Unregulated bulk): Powers non-critical circuits, max load 400 mA

• ±12 V dc (Isolated): Powers isolated circuits, max load 300 mA, unregulated

• +24 V dc (Isolated): Powers isolated circuits, max load 1.5 A, unregulated

2. Reset Function

The IS200RAPAG1B board provides logic supply undervoltage reset protection and master reset functions via the PSEN line on the P1 connector:

• Power-Up Reset: After the 5 V regulator input exceeds 9 V dc and the 5 V output exceeds 4.6 V dc, the PSEN line is held low for 100 milliseconds.

• Power-Down Reset: When the 5 V regulator input drops below 9 V dc, the PSEN line is asserted low.

• Manual Reset: Pressing the front panel master reset button pulls PSEN low; it remains low for 100 milliseconds after release.

• External Reset: An external board pulling PSEN low for a minimum of 30 microseconds forces a reset; PSEN will remain low for a minimum of 100 milliseconds or until the PSEN line is released.

3. Serial Board Identification

The IS200RAPAG1B board features a serial 1024-bit memory device pre-programmed with board identification and revision information. This information is accessible via the BRDID data line on the P1 connector, facilitating automatic board type and revision identification by the system.

4. Status Indication

The front panel features two green LED indicators:

• MPOK (Green): Monitors the PSEN logic line status. During normal operation, PSEN is high, and the LED is ON. During reset, PSEN is low, and the LED is OFF.

• IPOK (Green): Monitors the isolated 24 V power supply status. It is ON during normal operation. If this LED is OFF, check fuse FU1.

5. Test Points

The front panel provides four test points for convenient on-site measurement of key signals:

• TP1 (P5): Digital +5 V dc

• TP2 (DCOM): Digital Common

• TP3 (P15): Analog +15 V dc

• TP4 (N15): Analog -15 V dc

6. Overcurrent Protection

The board includes fuse FU1 (1 A, 250 V) to protect the isolated 24 V power supply. If the IPOK LED is OFF, this fuse should be checked first.

III. System Applications

1. Application in Innovation Series Control System

The IS200RAPAG1B is the core module providing power to other boards within the Innovation Series control system rack. Its roles within the system include:

• Central Power Supply: Provides multiple DC operating voltages for digital I/O boards, analog I/O boards, processor boards, etc., within the rack.

• System Reset Control: Provides power-up reset, power-down reset, manual reset, and external reset functions, ensuring reliable system reset during power anomalies or when required.

• Board Identification: Provides board identification information via serial memory, facilitating automatic hardware configuration recognition by the system.

• Status Monitoring: Indicates power and reset status via front panel LEDs, allowing operation and maintenance personnel to quickly assess board status.

2. Differences from G1A Version

Compared to the earlier G1A version, the IS200RAPAG1B version offers enhanced output current capability:

• +15 V Output: Increased from 400 mA (G1A) to 1.0 A

• +5 V Output: Increased from 4.75 A (G1A) to 7.0 A

• +24 V Output: Increased from 1.2 A (G1A) to 1.5 A

These enhancements allow the G1B version to support higher power loads, making it suitable for more complex control system configurations.

3. Typical Application Scenarios

• Innovation Series control system rack power supply

• Power supply for processor boards in industrial process control systems

• Auxiliary power for power plant excitation control systems

• Power module for rail transit control systems

• Rack power supply for marine automation systems

  
  

IV. Detailed Interface Description

1. P1 Connector

The IS200RAPAG1B board connects to other boards in the rack via the P1 backplane connector. P1 has three rows (A, B, C), each with 32 pins, totaling 96 pins. Key pin definitions are as follows:

Row A Key Pins:

Row B Key Pins:

Row C Key Pins:

2. Front Panel Interface

The front panel features:

• Reset Button: Manually triggers system reset

• LED DS1 (MPOK): Indicates PSEN status

• LED DS2 (IPOK): Indicates isolated 24 V power status

• Test Points TP1-TP4: For measuring key voltages

  
  

V. Indicators, Fuse, and Test Points

1. LED Indicators

2. Fuse

3. Test Points

VI. Installation and Replacement

1. Mounting Location

The IS200RAPAG1B board inserts into a designated slot in the Innovation Series board rack. The board is keyed for specific slots; inserting it into the wrong slot can damage electronics.

2. Replacement Procedure

Safety Warnings:

• WARNING: To prevent electric shock, turn off power to the drive system and use high-voltage test equipment to verify circuits are de-energized before touching.

• CAUTION: To prevent component damage caused by static electricity, treat all boards with static sensitive handling techniques. Wear a grounding strap and store boards in anti-static bags.

• The RAPA board does NOT support online replacement. Power must be off before replacement.

Removing the Old Board:

1. Verify Power Off: Ensure the drive system is completely de-energized.

2. Open Cabinet Door: Open the drive cabinet door. Use high-voltage test equipment to verify circuits are de-energized.

3. Loosen Screws: Loosen the screws at the top and bottom of the board near the ejector tabs (screws are captive, do not remove).

4. Extract Board: Unseat the board by raising the ejector tabs. Gently pull the board straight out of the rack using both hands.

Installing the New Board:

1. Insert Board: Align the new board with the correct slot and push it in along the guides.

2. Seat Board: Using thumbs, firmly press the top and bottom of the board simultaneously to initially seat it.

3. Tighten Screws: Alternately tighten the top and bottom screws evenly to ensure the board is squarely seated.