Yokogawa SEC Series Modules

Technical Dossier

Product Details And Specifications

Yokogawa SEC Series: Comprehensive Module Range and Technical Overview

The Yokogawa SEC (Station Equipment Controller) series represents a core hardware layer within Yokogawa's STARDOM and Vnet/IP distributed control architecture. Deployed extensively across global heavy industry — including petrochemical complexes, nuclear power auxiliary systems, crude oil refineries, and LNG terminals — SEC series modules serve as the physical interface between field instrumentation and the supervisory control network. Their ruggedized backplane design, deterministic bus communication, and compliance with IEC 61511 functional safety standards have made them a long-term fixture in facilities where replacement cycles span 15–25 years. The SEC401-11 Bus Coupler Module specifically functions as the communication bridge between the Vnet/IP control network and field I/O station buses, making it a single point of criticality in multi-loop process control environments.

The Evolution of SEC Series Architecture

The SEC series was introduced as part of Yokogawa's transition from the legacy CENTUM CS 3000 hardware ecosystem toward the STARDOM FCN/FCJ autonomous controller platform and the Vnet/IP real-time Ethernet control network. Early-generation SEC modules were designed around a proprietary ESB (Enhanced Station Bus) backplane, offering deterministic scan times in the 10–100 ms range for analog and discrete I/O. As Yokogawa migrated toward Vnet/IP — a 1 Gbps redundant Ethernet backbone — the SEC series was re-engineered to support dual-ring redundancy, hot-standby controller failover, and online module replacement without process interruption.

Compatibility considerations are significant for maintenance engineers: first-generation SEC modules (pre-2005 firmware) are not directly interchangeable with post-2010 revisions without backplane firmware alignment. The SEC401-11 and its variants require matching firmware on the FCN controller node to which they are coupled. Facilities running mixed-generation hardware must verify ESB address assignments and Vnet/IP node IDs before substitution. Yokogawa officially entered the end-of-active-production phase for several SEC module variants after 2018, though long-term repair and spare parts support remains available through authorized distributors and specialist suppliers such as DriveKNMS.

SEC Series Full Catalog & Functionalities (SKU List)

The following represents a structured index of confirmed SEC series module part numbers, organized by functional category. Each entry reflects a discrete hardware unit with a defined role within the STARDOM/Vnet/IP station architecture.

Bus Coupler & Communication Modules

• SEC401-11: Vnet/IP-to-ESB bus coupler; bridges control network to field I/O station bus.
• SEC401-12: Redundant bus coupler variant; supports dual ESB ring for high-availability stations.
• SEC411-11: ESB repeater module; extends station bus segment length in large I/O configurations.
• SEC421-11: Optical ESB coupler; fiber-optic bus isolation for electrically noisy environments.

Analog Input Modules

• SEC301-11: 8-channel analog input; 4–20 mA, HART pass-through, 16-bit resolution.
• SEC301-12: 16-channel analog input; high-density field termination, 4–20 mA.
• SEC302-11: Thermocouple/RTD input module; supports J, K, T, Pt100 sensor types.
• SEC303-11: High-speed analog input; 1 ms scan for fast-loop pressure and flow applications.

Analog Output Modules

• SEC311-11: 8-channel analog output; 4–20 mA, loop-powered, HART-capable.
• SEC311-12: 16-channel analog output; high-density valve and actuator control.
• SEC312-11: Isolated analog output; galvanic isolation per channel for hazardous area loops.

Digital Input Modules

• SEC201-11: 32-channel DI module; 24 VDC, dry contact and wet contact selectable.
• SEC202-11: 16-channel DI module; high-voltage input, 110/220 VAC compatible.
• SEC203-11: Pulse input module; frequency and totalizer functions for flow metering.

Digital Output Modules

• SEC211-11: 32-channel DO module; 24 VDC transistor output, short-circuit protected.
• SEC212-11: 16-channel relay output; SPDT contacts, 2A per channel, for motor starter control.

Power Supply Modules

• SEC101-11: Station power supply; 24 VDC output, 10A, redundant pair capable.
• SEC102-11: Redundant power supply module; hot-swap replacement without station shutdown.

Sourcing Hard-to-Find & Obsolete SEC Series Parts

DriveKNMS maintains a dedicated inventory program for Yokogawa SEC series modules that have entered end-of-production or limited-availability status. For facilities operating STARDOM FCN/FCJ systems installed between 2003 and 2015, the probability of encountering discontinued SEC module variants during unplanned maintenance events is high. Standard Yokogawa distribution channels may carry lead times of 16–26 weeks for low-volume legacy parts, or may no longer list them as orderable.

DriveKNMS sources SEC series modules through a combination of manufacturer-certified new-old-stock (NOS), factory-refurbished units, and tested-functional pull inventory from decommissioned process plants. All units are cross-referenced against Yokogawa's official part number database before listing. For critical bus coupler modules such as the SEC401-11, DriveKNMS maintains buffer stock to support emergency dispatch requirements. Customers are encouraged to submit their full BOM (Bill of Materials) for multi-module procurement to receive consolidated availability confirmation and lead time estimates.

Quality Control for the SEC Series Range

SEC series modules present specific test challenges due to their integrated backplane bus logic and Vnet/IP protocol stack. DriveKNMS applies a structured verification protocol to all SEC units prior to dispatch:

• Visual and mechanical inspection: Connector pin integrity, PCB surface condition, capacitor health check, and housing latch function.
• Backplane bus communication test: Each module is seated in a live SEC-compatible test rack and ESB communication is verified at the protocol level using Yokogawa-compatible diagnostic tools.
• Analog channel calibration: For SEC301/302/311/312 variants, all I/O channels are calibrated against NIST-traceable reference standards. Deviation tolerance: ±0.05% of full scale.
• Digital I/O functional test: All DI/DO channels are exercised through full on/off cycles with load simulation.
• Firmware version verification: Module firmware is documented and reported to the customer to confirm compatibility with the target FCN controller revision.
• Burn-in cycle: Modules are powered continuously for a minimum of 24 hours under thermal load before final packaging.

Each unit ships with a DriveKNMS test report documenting channel-level results, firmware version, and inspector sign-off.

For SEC401-11 availability, bulk SEC series procurement, or emergency spare parts support:

• Email: [email protected]
• WhatsApp: +86 18359293191
• Web: driveknms.com