System architecture and extension logic
1. Hardware architecture and redundancy design
FCN-RTU adopts a layered architecture of "main unit+expansion unit+remote I/O", balancing flexibility and reliability:
Main unit: including CPU module, power module, basic I/O module and communication module, supporting DIN rail installation (size: 140 × 100 × 220mm, weight about 2.5kg), suitable for small control cabinets or outdoor cabinets;
Expansion Unit: Connected to the main unit via RS-485 or fiber optic cables, providing additional I/O interfaces (such as AI/AO/DI/DO modules). A single main unit can cascade up to 8 expansion units, suitable for centralized monitoring of multiple devices;
Redundant configuration: The CPU, power supply, and wireless communication module can be redundant with a redundancy switching time of less than 100ms. The communication link supports "wireless+wired" dual backup (such as 4G and fiber optic redundancy) to avoid disconnection caused by a single link failure.
2. Typical System Topology Example
plaintext
[Center SCADA/DCS] ←→ [Communication Network (4G/Satellite/Fiber Optic)] ←→ [FCN-RTU Main Unit (Redundant CPU+Power Supply)]
↓ (RS-485/fiber optic)
[Extension Unit 1 (AI/TC Module)] ←→ [Pipeline Pressure/Temperature Sensor]
↓
[Expansion Unit 2 (DI/DO Module)] ← → [Pump Station Motor/Valve actuator]
↓
[Expansion Unit 3 (Pulse Module)] ←→ [Flow Meter (Pulse Output)]
Engineering development and operation characteristics
1. Programming and configuration tools
FCN-RTU is equipped with Yokogawa STARDOM Engineering Tool kit, which complies with IEC 61131-3 standard and reduces the development threshold:
Control Designer: a control program development tool that supports FBD (Function Block Diagram), LD (Ladder Diagram), and ST (Structured Text) programming, and provides industry-specific function block libraries (such as oil and gas pipeline leak detection blocks and flow accumulation blocks);
System Configurator: a hardware configuration and communication parameter setting tool that visualizes the mapping of logical I/O and physical modules. It supports one click configuration of communication protocol parameters (such as DNP3.0) without the need to manually write drivers;
Offline Simulator: an offline simulation tool that can simulate on-site signals (such as pressure fluctuations and valve failures) on a PC, verify the correctness of control logic, and shorten on-site debugging time.
2. Operations and diagnostic capabilities
Low power operation and maintenance: supports "sleep wake" mode (such as sleep when there is no data, timed wake-up upload), and can achieve continuous 72 hour operation without sunlight in the scenario of solar+battery power supply;
Status monitoring and alarm: The main unit is equipped with an LCD display screen (128 × 64 pixels) and LED indicator lights, which display the real-time operating status (power, communication, I/O faults); Support local button operation (fixed value modification, log query), or export fault logs through USB interface;
Remote operation and maintenance: Remote diagnosis can be achieved through a web interface or Yokogawa PRM (Plant Resource Manager) system, supporting I/O channel calibration, firmware online upgrade, configuration file backup/recovery, and reducing on-site operation and maintenance frequency.
Key modules and selection information
1. Core module model and function
Module Type Model Example Core Functions
CPU module F3CU01 single CPU configuration, 1 Ethernet+2 RS-485, supports Modbus/DNP3 protocol
F3CU02 redundant CPU configuration, 2 Ethernet (redundant)+2 RS-485, suitable for high reliability scenarios
Power module F3PU01 12-48V DC input, single output (5V+24V), supports battery charging management
F3PU02 redundant power module, dual independent outputs, supports fault self detection
Analog input module F3AI08 8-channel 4-20mA input, channel isolation, accuracy ± 0.1% FS, supports HART protocol (optional)
F3AR08 8-channel RTD input (platinum resistance 100 Ω), supporting wire breakage detection and cold end compensation
Communication module F3CM4G 4G/LTE wireless module, dual card redundancy, supports global frequency bands (1.8/2.1GHz)
F3CMSAT satellite communication module, compatible with Inmarsat BGAN network, supports communication in remote areas without base stations
Expansion module F3EX01 expansion bus interface module, realizing RS-485/fiber optic connection between the main unit and the expansion unit
2. Key dimensions for selection
I/O requirements: Determine the number of AI/AO/DI/DO points based on the type of on-site equipment (sensors/actuators), and select the number of basic I/O modules and expansion units for the main unit;
Communication environment: Satellite communication module is selected for areas without base stations, 4G/LTE module is selected for areas with mobile signals (dual card redundancy priority), and fiber optic+wireless backup is optional for fixed stations;
Environmental conditions: Choose IP65 protection and G3 coating for outdoor or harsh environments, support wide temperature range (-40 ℃) for low-temperature scenarios, and select ATEX certified models for hazardous areas;
Email:wang@kongjiangauto.com