The CI830 Fieldbus Communication Interface (FCI) is a high-performance, modular, and intelligent communication interface designed by ABB for the S800 I/O system. It serves as a critical bridge between the upper-level controller (via the PROFIBUS-DP fieldbus) and the underlying S800 I/O modules (via the ModuleBus). The CI830 not only enables high-speed and reliable data exchange but also integrates power management, status monitoring, and configuration management functions, making it a core component for building distributed automation systems.
The CI830 is designed for industrial environments, featuring high reliability, strong anti-interference capability, and flexible configuration options. It supports the standard PROFIBUS-DP protocol with communication speeds ranging from 9.6 kbit/s to 12 Mbit/s, meeting the real-time and data volume requirements of most industrial automation applications. Furthermore, the CI830 provides stable and secure power for itself and connected I/O modules through its internally isolated power conversion circuitry.
This interface module features a compact DIN rail mounting design for easy integration within control cabinets. Its front panel provides intuitive status indicators, address setting switches, and necessary communication ports, facilitating installation, commissioning, and maintenance.
2. Product Structure and Appearance
The CI830 FCI module has a compact structure with a clearly laid-out front panel, primarily consisting of the following parts:
Address Switches: Two decimal rotary switches used to set the station address (range 01-79) within the PROFIBUS-DP network.
Status Indicators (LEDs): Used to indicate module fault, operational state, power status, PROFIBUS communication status, and optical ModuleBus communication status.
Communication Ports:
Power Supply Terminals: Screw terminals for connecting the 24 V DC power supply and redundant power supply monitoring.
ModuleBus Connector: For connecting the TB810/TB811 optical ModuleBus converter or the electrical ModuleBus.
Internally, the module is mainly composed of four circuit boards:
Processor Board: Contains the CPU, memory, PROFIBUS-DP protocol chip, ModuleBus interfaces, and LED driver circuits.
Power Supply Board: Contains an isolated DC/DC converter that provides +5V power for the module and I/O modules, and integrates opto-isolated RS-232 drivers/receivers for the service port.
Termination Board: Acts as the main hub for external connections, providing power terminals, communication port connectors, and is grounded to the DIN rail via a metallic spring connector.
Optical Port: For connecting the optical ModuleBus.
3. Key Features and Functions
PROFIBUS-DP Slave Interface: Fully compliant with the PROFIBUS-DP standard, enabling high-speed data exchange with the master control system.
S800 ModuleBus Master Management: Manages and controls all connected S800 I/O modules, facilitating centralized data acquisition and distribution.
Intelligent Power Management: Features a built-in isolated power supply that provides stable +5V and +24V power to subsequent I/O modules, with short-circuit protection.
Redundant Power Supply Monitoring: Provides two independent power supply monitoring inputs (SA, SB), supporting redundant power configurations to enhance system availability.
Comprehensive Status Diagnostics: Real-time display of module operation, communication, power, and fault status via multi-colored LED indicators on the front panel.
Flexible Configuration Capability: Supports various combinations of S800 I/O modules, with detailed configuration rules ensuring system performance.
Convenient Maintenance and Upgrades: Firmware upgrades and fault diagnosis can be easily performed via the isolated RS-232 service port.
Robust Industrial Design: Complies with IP20 protection rating, operates over a wide temperature range, and uses DIN rail mounting.
4. Interfaces and Connections
4.1 Power Supply Connections (X1)
| Pin | Designation | Description |
| 4 | L+ | +24 V DC Supply Input |
| 3 | L- | 0 V DC Supply Input (Ground) |
| 2 | SA | Redundant Power Supply “A” Monitoring Input |
| 1 | SB | Redundant Power Supply “B” Monitoring Input |
4.2 PROFIBUS-DP Connections (X2)
| Pin | Designation | Description |
| 1 | Shield | Shield/Protective Ground |
| 2 | - | Not used |
| 3 | RxD/TxD-P | Receive/Transmit Data - Plus |
| 4 | - | Not used |
| 5 | DGND | Data Ground |
| 6 | VP | Supply Voltage for the Terminating Resistors |
| 7 | - | Not used |
| 8 | RxD/TxD-N | Receive/Transmit Data - Minus |
| 9 | - | Not used |
4.3 Service Port Connections (X3)
| Pin | Designation | Description |
| 2 | TD | Transmit Data (Channel B) |
| 3 | RD | Receive Data (Channel B) |
| 5 | SG | Signal Ground |
| 7 | RDA | Receive Data (Channel A, for debugging only) |
| 8 | TDA | Transmit Data (Channel A, for debugging only) |
5. Configuration Rules and Limitations
The configuration of the CI830 must adhere to the limitations of the PROFIBUS-DP protocol and the module's own capabilities to ensure stable system operation.
System-Level Limitations:
Maximum Number of Stations per PROFIBUS Bus: 79
Maximum Number of Stations per PROFIBUS Bus Segment: 32
Maximum Number of I/O Modules per Station (CI830): 24
Maximum Number of I/O Modules per Cluster: 12 (Physically installing more than 12 MTUs and/or S800L modules in one cluster is not allowed)
Module Type Quantity Limits (based on CI830):
Due to PROFIBUS-DP data throughput limitations, not all modules can reach the theoretical maximum of 24. The maximum number of connectable modules for major types is as follows:
| Module Type | Maximum Number |
| AI801, AI810, AI830, AI830A, AI835, AI835A, AI890, AI893 | 12 |
| AI820, AI825 | 20 |
| AO801, AO810, AO810V2, AO890 | 13 |
| AO820 | 21 |
| DP820 | 11 |
| DP840 | 6 |
| All DI and DO modules | 24 |
| ABB Standard Drive | 17 or 24 (see detailed configuration table) |
Configuration Verification Method:
To ensure a specific combination of analog and digital modules is feasible, the Configuration Calculation Table (based on Table 11 in the document) must be used for verification. The main steps are as follows:
Fill in Module Quantities: Enter the planned quantity for each module type in the table.
Calculate Three Column Sums: Calculate the "Sum User Parameters", "Sum Input Bytes", and "Sum Output Bytes" separately.
Calculate Three Total Limits:
Check First-Level Limits:
Round Up Values: Round up InSize, OutSize, and (ParamSize + 15) to the nearest multiple of eight (e.g., 233 rounds to 240).
Calculate Memory Usage: Use the formula MemSize = a + 2*RoundParamSize + 3*(RoundInSize + RoundOutSize).
Check Final Limit: MemSize must be ≤ 2048. Otherwise, the configuration is invalid.
6. Status Indication and Diagnostics
The LED indicators on the CI830 front panel provide comprehensive status and diagnostic information for quick troubleshooting.
| LED Designation | Color | Status Description |
| F (Fault) | Red | Indicates an internal module fault. Lights up at power-up, module restart, or when entering an error state. Turns off after a successful startup self-test. |
| R (Run) | Green | Indicates operational state. Lights up during normal operation. |
| P (Power ok) | Green | Lights up when the internal power is OK. |
| RX (Receive) | Yellow | Flashes when data is being received on the PROFIBUS. |
| TX (Transmit) | Yellow | Flashes when data is being transmitted on the PROFIBUS. |
| Tx (TB810/TB811) | Yellow | Flashes when data is being transmitted on the optical ModuleBus. |
| Rx (TB810/TB811) | Yellow | Flashes when data is being received on the optical ModuleBus. |
7. Software Upgrade and Maintenance
Hardware Requirements:
Upgrade Procedure:
Connection: Connect the PC's COM1/COM2 port to the CI830 service port (X3) using the TK527 cable.
Run Upgrade Program: Execute loader32.exe on the PC.
Parameter Settings: Select "User defined" and manually specify the COM port and the path to the upgrade file.
Critical Setting: Must check the "Disable optimization of speed (Fix to 9600 BD)" checkbox and uncheck other boxes.
Download: Click the "Download" button to start the upgrade. The process takes approximately 5 minutes.
Troubleshooting:
Problem: Cable disconnection or power interruption during the upgrade.
Solution: Switch the CI830 power OFF and then ON again to restart the module, then repeat the upgrade procedure.
