YOKOGAWA ATT4S-00 S2 Analog I/O Module – CENTUM VP

YOKOGAWA ATT4S-00 S2 — Analog Signal Interface Module in CENTUM VP / CS 3000 Field Control Architecture

The ATT4S-00 S2 is a dedicated analog input/output module manufactured by YOKOGAWA Electric Corporation, designed to operate within the Field Control Station (FCS) I/O nest of the CENTUM VP and CENTUM CS 3000 Distributed Control System platforms. Its primary function is to serve as the electrical and logical boundary between field-level process instruments and the DCS controller bus, performing signal conditioning, analog-to-digital conversion, galvanic isolation, and bus-formatted data transmission in a single compact module footprint.

Unlike generic I/O cards, the ATT4S-00 S2 is tightly coupled to YOKOGAWA’s proprietary V-net/ER backplane bus architecture. Each module slot in the FCS nest is addressed deterministically, and the S2 revision introduces an onboard EEPROM that stores module identity, channel configuration, and hardware revision data. Upon insertion, the CENTUM VP Engineering Environment reads this EEPROM automatically, eliminating manual parameter entry and reducing commissioning risk in multi-loop installations.

Real-time Stock & RFQ: [email protected] | WhatsApp: +86 18359268345

Technical Parameters

Hardware Logical Analysis

Photoelectric Isolation Architecture
Each analog channel on the ATT4S-00 S2 passes through a two-stage isolation barrier. The first stage uses optocoupler-based galvanic isolation to decouple the field wiring ground reference from the DCS backplane ground, preventing ground loop currents from corrupting the A/D conversion result. The second stage applies a DC-DC isolated power converter to supply the field-side circuitry independently, ensuring that a field-side fault — including a short to earth — does not propagate into the FCS processor or adjacent modules. This dual-barrier design meets IEC 61010-1 reinforced insulation requirements for industrial measurement circuits.

EMC Design and Noise Rejection
The S2 revision incorporates a multi-layer PCB with dedicated ground planes separating the analog front-end, digital processing, and bus interface sections. Ferrite bead filters are placed at the terminal block entry points to attenuate high-frequency conducted interference from field cable runs. The module’s metal housing provides shielding continuity with the FCS nest chassis, contributing to the system’s overall IEC 61000-4-3 radiated immunity performance. In environments with variable-frequency drives or high-current switching equipment nearby, this shielding architecture maintains signal integrity without requiring additional external filtering.

Onboard EEPROM and Auto-Recognition Logic
The S2 hardware revision introduced a non-volatile EEPROM that stores the module’s part number, hardware revision code, channel count, and factory calibration coefficients. When the FCS powers up or a hot-swap event is detected, the backplane controller reads this EEPROM via the I²C sideband bus before enabling the module’s V-net/ER data path. This sequence prevents the FCS from attempting to communicate with an incompatible module type and allows the CENTUM VP Engineering Environment to flag revision mismatches before they affect process control.

Backplane Bus Arbitration
The ATT4S-00 S2 participates in the V-net/ER bus as a slave node. The FCS processor issues cyclic scan commands at a fixed interval (typically 100 ms for standard analog loops, configurable down to 50 ms for fast-scan applications). The module’s local microcontroller buffers the most recent A/D conversion result and responds to the bus master’s poll within the guaranteed slot time, ensuring deterministic data delivery to the FCS control calculation engine. Bus timeout detection is handled in hardware: if the module fails to respond within two consecutive scan cycles, the FCS flags the channel as faulty and substitutes the configured fallback value, maintaining loop integrity.

System Integration Benefits

• Zero-configuration insertion: The EEPROM auto-recognition mechanism allows the CENTUM VP Engineering Environment to detect module type and revision upon insertion, with no manual parameter entry required — reducing commissioning time per module by an estimated 15–20 minutes in multi-nest installations.
• Hot-swap without process interruption: The ATT4S-00 S2 supports online module replacement while the FCS remains in control mode, subject to the system’s hot-swap configuration. Channels on the replaced module enter a configurable hold-last-value or fallback state during the swap window, preserving loop stability.
• Deterministic scan cycle compliance: The module’s local buffering and bus arbitration logic guarantee response within the FCS scan slot, supporting real-time control loops with cycle times as short as 50 ms without introducing jitter that would degrade PID performance.
• Dual-barrier isolation for ground loop immunity: The two-stage galvanic isolation eliminates ground loop interference from long field cable runs — a common source of 4–20 mA signal drift in large process plants — without requiring external isolators or signal conditioners.
• Integrated diagnostic transparency: Channel-level fault codes (open circuit, over-range, under-range, A/D saturation) are reported directly to the CENTUM VP HMI via the FCS diagnostic data path, enabling maintenance personnel to identify the specific channel and fault type without physical inspection of the I/O nest.
• Backward compatibility with S1 hardware: The ATT4S-00 S2 is pin-compatible and bus-compatible with the S1 revision, allowing direct replacement in existing FCS nests without mechanical or wiring modifications. The CENTUM VP Engineering Environment recognizes both revisions and applies the appropriate driver automatically.
• Reduced spare parts complexity: As a mixed analog I/O module, the ATT4S-00 S2 can serve both input and output functions depending on channel configuration, reducing the number of distinct spare part numbers required in a plant’s maintenance inventory.
• Compliance with IEC 61000-4 EMC immunity standards: The module’s multi-layer PCB, ferrite filtering, and chassis shielding collectively meet the conducted and radiated immunity levels specified in IEC 61000-4-4 (EFT/burst), IEC 61000-4-5 (surge), and IEC 61000-4-6 (conducted RF), making it suitable for installation in electrical rooms adjacent to high-power switching equipment.

Quality Assurance & Global Logistics

Every ATT4S-00 S2 unit supplied by siemensplc.com is sourced as genuine YOKOGAWA OEM hardware. Prior to dispatch, each module undergoes a structured pre-shipment inspection protocol: visual examination of the PCB, terminal block, and housing for physical damage; label and part number verification against the YOKOGAWA part database; and a functional power-on check to confirm the module’s EEPROM responds correctly and no fault LEDs are active at initialization.

Units are packaged in anti-static ESD shielding bags, placed in foam-padded inner cartons, and enclosed in double-wall corrugated outer cartons rated for international air freight handling. Shipments originate from our warehouse in Xiamen, China, with standard dispatch within 1–3 business days of order confirmation. International delivery is handled via DHL Express, FedEx International Priority, or UPS Worldwide Expedited, with typical transit times of 3–7 business days to Europe, North America, Southeast Asia, and the Middle East. Full tracking information is provided at the time of shipment.

For customers requiring export documentation, we provide a commercial invoice, packing list, and certificate of origin. HS Code 8537.10 applies to this product category for customs classification purposes. Customers in regions with import duty exemptions for industrial automation components should confirm applicability with their customs broker prior to order placement.

A 12-month warranty is provided from the date of shipment, covering manufacturing defects and functional failures under normal operating conditions as defined in YOKOGAWA’s product documentation. Warranty claims are processed with a target response time of 2 business days.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
Location: Xiamen, China
© 2026 siemensplc.com. All rights reserved.