The IS200WROBH1A is a Relay Output Option Board designed by General Electric (GE) for its Mark VIe Control System. This board serves as an expansion option for the TDBT terminal board. When used in conjunction with the TDBT, it achieves the same relay circuit functionality as the IS200TRLYH1B terminal board in Triple Modular Redundant (TMR) systems.
The core function of the IS200WROBH1A board is to provide fused power distribution for the first six relays of the TDBT and dedicated power for the last relay (relay 12). The power distribution circuit on the board features double-ended fusing, allowing its use in systems where the DC power supply is floating with respect to ground. Fuse voltage feedback is compatible with 24 V, 48 V, and 125 V DC applications, as well as 120 V and 240 V AC applications.
Key features of the WROBH1A include:
TDBT Functionality Expansion: Works with the TDBT to provide a complete relay output solution.
Double-Ended Fuse Protection: Both positive and negative sides of each output are fused, suitable for floating power supply systems.
Multi-Voltage Compatibility: Supports 24/48/125 V dc and 120/240 V ac applications.
Default Fuse Rating: Factory default fuses are 3.15 A.
Configurable Jumpers: Six jumpers select whether to supply power to the corresponding relay.
MOV Snubber: Metal Oxide Varistors across normally open contacts provide transient overvoltage protection.
Isolated Voltage Feedback: Provides fuse status feedback to all three PDIOs.
ID Chip Identification: The board features three ID chips, one for each PDIO, ensuring hardware compatibility.
The board utilizes surface-mount technology, has dimensions matching the TDBT, and operates within a temperature range of -30 to 65°C, making it suitable for industrial field environments.
II. Main Functions
The primary functions of the IS200WROBH1A include, but are not limited to, the following:
1. Power Distribution for TDBT Relays
The IS200WROBH1A provides fused power distribution for the first six relays (relays 1-6) of the TDBT. Both the positive and negative sides of each output circuit are fused. This design allows operation in systems where the DC power supply is floating with respect to ground, enhancing system flexibility.
2. Dedicated Power Output
Provides one unfused dedicated power output for the last relay (relay 12) of the TDBT, supplied via the JG1 connector.
3. Fuse Status Monitoring
The IS200WROBH1A provides isolated voltage feedback to all three PDIOs regarding the status of the fuses. When a fuse blows, the PDIO can detect this status and generate a corresponding diagnostic alarm.
4. MOV Snubber Protection
Each relay's normally open contact is paralleled with a Metal Oxide Varistor (MOV) to suppress back EMF generated when switching off inductive loads. This protects the contacts from arcing damage and extends relay life.
5. Configurable Power Supply Jumpers
The IS200WROBH1A features six jumpers (corresponding to relays 1-6) to select whether to supply power to the corresponding relay:
Jumper Installed: Supplies power to the relay (default state).
Jumper Removed: Relay operates as a dry contact, with no power distribution provided.
6. Hardware ID Identification
The board features three read-only ID chips, corresponding to the three PDIOs (R, S, T). These chips store the board's serial number, type, and revision information. The PDIO reads this information during initialization. If a mismatch is encountered, a hardware incompatibility fault is generated.
7. Electrical Combination with TDBT
When the IS200WROBH1A is used with the TDBT, the electrical combination forms a relay circuit equivalent to the TRLYH1B, including:
6 outputs with fused power distribution protection.
1 dedicated power output.
Position feedback for all relays.
Fuse status feedback.
III. System Applications
1. Application in Mark VI Control System
The IS200WROBH1A, as an option board for the TDBT terminal board, expands the relay output functionality within the Mark VI control system. Used in conjunction with the TDBT, it is primarily applied in the following scenarios:
Triple Modular Redundant (TMR) Systems: Provides relay circuit functionality equivalent to the TRLYH1B.
Power Distribution: Provides fused power for the first six relays.
Dry Contact Applications: Configures relays as dry contact outputs by removing jumpers.
Floating Power Supply Systems: The double-ended fuse design allows operation in systems where the DC power supply is floating with respect to ground.
2. Combination Use with TDBT
The IS200WROBH1A must be used in conjunction with the TDBT terminal board and cannot function alone. The combined system features:
12 Relay Channels: TDBT provides 12 relays.
6 Fused Protection Outputs: IS200WROBH1A provides fused power for the first 6 relays.
1 Dedicated Output: Provides dedicated power for the 12th relay.
5 Dry Contact Outputs: The remaining relays can be used as dry contacts.
Complete Feedback: Includes relay position feedback and fuse status feedback.
3. Typical Application Scenarios
Generator Breaker Control: Controls generator breakers via fused relay outputs.
Excitation System Control: Controls interposing relays in EX2100 excitation systems.
Alarm Outputs: Configured as dry contacts to output alarm signals to DCS or higher-level systems.
Valve Control: Controls various solenoid valves, pneumatic valves, and other actuators.
Pump/Fan Start/Stop Control: Controls motor starters via relay outputs.
IV. Detailed Interface Description
1. Power Input Connectors
| Connector | Description |
|---|
| JF1 | Power Input Connector 1 (paralleled with JF2) |
| JF2 | Power Input Connector 2 (paralleled with JF1) |
The two connectors are paralleled, providing power input for the first six relays.
2. Dedicated Power Connector
| Connector | Description |
|---|
| JG1 | Provides dedicated power for relay 12 (unfused) |
3. Fuse and Relay Correspondence
| Positive Fuse | Negative Fuse | Jumper | Corresponding Terminals | Corresponding Relay |
|---|
| FU7 | FU1 | JP1 | 1-4 | Relay 1 |
| FU8 | FU2 | JP2 | 5-8 | Relay 2 |
| FU9 | FU3 | JP3 | 9-12 | Relay 3 |
| FU10 | FU4 | JP4 | 13-16 | Relay 4 |
| FU11 | FU5 | JP5 | 17-20 | Relay 5 |
| FU12 | FU6 | JP6 | 21-24 | Relay 6 |
4. Jumper Configuration
| Jumper | Function | Default State |
|---|
| JP1 | Controls power supply for relay 1 | Installed (Power supplied) |
| JP2 | Controls power supply for relay 2 | Installed (Power supplied) |
| JP3 | Controls power supply for relay 3 | Installed (Power supplied) |
| JP4 | Controls power supply for relay 4 | Installed (Power supplied) |
| JP5 | Controls power supply for relay 5 | Installed (Power supplied) |
| JP6 | Controls power supply for relay 6 | Installed (Power supplied) |
5. ID Chips
The IS200WROBH1A features three ID chips, corresponding to the three PDIOs:
Chip 1: Corresponds to PDIO R
Chip 2: Corresponds to PDIO S
Chip 3: Corresponds to PDIO T
Each chip stores the following information:
V. Diagnostics and Maintenance
1. Diagnostic Functions
The PDIO performs the following diagnostics on the TDBT and IS200WROBH1A:
| Diagnostic Item | Description |
|---|
| Contact Wetting Voltage Monitoring | Monitors the contact wetting voltage. If the voltage drops below 40% of the nominal value, a diagnostic alarm (fault) is set and latched. |
| Relay Position Feedback | Provides relay status feedback to all three PDIOs by monitoring an isolated set of contacts on each relay. |
| Fuse Status Feedback | Provides status information for the six fuse pairs to all three PDIOs via isolated voltage feedback. |
| ID Chip Verification | Reads the three ID chips on the IS200WROBH1A and compares them with expected values. A mismatch generates a hardware incompatibility fault. |
2. Common Troubleshooting
| Fault Symptom | Possible Cause | Troubleshooting Suggestions |
|---|
| Relay does not operate | Power supply jumper not installed, blown fuse, power supply failure | Check JP1-JP6 jumpers, check fuses FU1-FU12, check power input |
| Contact wetting voltage alarm | Power supply voltage too low, power supply failure | Check if power supply voltage is within allowable range |
| Fuse status alarm | Corresponding fuse blown, load short circuit | Check the corresponding fuse, check the load circuit |
| Hardware incompatibility fault | ID chip information mismatch | Verify correct board model, contact GE technical support |
3. Maintenance Recommendations
Periodic Inspection: Regularly check fuse status and relay feedback via PDIO diagnostic functions.
Fuse Replacement: If a fuse is found blown, first troubleshoot the load fault, then replace with a fuse of the same rating.
Jumper Check: When modifying relay usage, ensure the corresponding jumpers are correctly configured.
Cleaning: Regularly clean the board to prevent dust accumulation affecting heat dissipation and insulation.
ESD Protection: Wear a grounding strap when handling the board and store it in anti-static bags.
VI. Configuration and Installation
1. Configuration Method
The IS200WROBH1A is configured primarily via jumpers:
| Configuration Item | Configuration Method | Description |
|---|
| Relay Power Supply Selection | JP1-JP6 | Jumper installed: Supplies power to corresponding relay; Jumper removed: Relay used as dry contact |
2. Jumper Setting Procedure
Determine the purpose of each relay.
To supply power to the relay, keep the jumper installed (default state).
To use the relay as a dry contact, remove the corresponding jumper.
Record the jumper settings for future maintenance.
3. Installation Steps
Verify Power Off: Ensure the system is completely de-energized.
Open Cabinet Door: Open the control cabinet door.
Install WROB: Correctly install the IS200WROBH1A into the designated position on the TDBT.
Connect Cables: Connect the JF1/JF2 power input cables and the JG1 dedicated power cable.
Check Jumpers: Verify that JP1-JP6 are set correctly.
Restore Power: Close the cabinet door and restore power to the system.
Verify Functionality: Verify normal board operation via PDIO diagnostic functions.
