Foxboro I/A Series Modules: P0971WV DNBT Dual Nodebus Module —

Technical Dossier

Product Details And Specifications

Foxboro I/A Series: Comprehensive Module Range and Technical Overview

The Foxboro I/A Series (Intelligent Automation Series) is one of the most widely deployed Distributed Control System (DCS) platforms in global heavy industry. Installed across petrochemical complexes, nuclear power stations, crude oil refineries, pulp and paper mills, and large-scale chemical processing facilities, the I/A Series has maintained a dominant installed base since its commercial introduction in the mid-1980s. Its modular, redundant architecture — built around the Nodebus and Fieldbus communication backbones — enabled plant operators to achieve high-availability control loops with deterministic scan rates. The P0971WV DNBT Dual Nodebus Module is a critical backplane communication component within this ecosystem, providing dual-path Nodebus connectivity for fault-tolerant data transmission between I/A Series workstations and field control processors (FCPs/FCMs).

The Evolution of I/A Series Architecture

The I/A Series architecture has undergone several major generational transitions since its inception. The original platform (circa 1987) relied on a 10 Mbps Nodebus coaxial network connecting Workstations, Application Workstations (AW), and Control Processors (CP). The introduction of the 100 Mbps Nodebus (Dual Nodebus, DNBT) in the mid-1990s doubled redundancy and bandwidth, directly enabling modules such as the P0971WV DNBT. The subsequent migration to Ethernet-based Mesh Control Network (MCN) in the 2000s introduced FCP270 and FCM100 series processors, while legacy CP10, CP30, CP40, and CP60 processors remained in service at thousands of sites globally. Compatibility between generations is constrained by backplane slot type, Nodebus protocol version, and power supply rail specifications. Sites running pre-2000 hardware must source original-specification modules; cross-generation substitution is not supported without engineering validation.

I/A Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced components within the Foxboro I/A Series platform, organized by functional category:

Nodebus & Communication Modules

• P0971WV DNBT: Dual Nodebus Transceiver Module; provides redundant Nodebus A/B path connectivity for I/A Series control enclosures.
• P0971KS: Single Nodebus Interface Module; used in non-redundant Nodebus segments for CP10/CP30 processors.
• P0971KT: Nodebus Terminator Module; required at each physical end of a Nodebus segment to prevent signal reflection.
• P0971KU: Nodebus Repeater Module; extends Nodebus segment length beyond the standard 300-meter limit.
• P0971GS: Fieldbus Module Interface; bridges I/A Series Fieldbus to field device clusters in legacy installations.

Control Processors

• P0914TQ: CP40B Control Processor; 32-bit processor module for mid-range I/A Series control enclosures, supports up to 2000 I/O points.
• P0914YE: CP60 Control Processor; high-capacity processor for large-scale process control, supports redundant configuration.
• FCP270: Field Control Processor 270; Ethernet-based FCP for MCN-generation I/A Series, supports HART and Foundation Fieldbus.
• FCM100Et: Field Control Module 100 Ethernet; remote I/O controller for distributed field enclosures.
• P0914XS: CP40 Control Processor (earlier revision); functionally equivalent to CP40B with reduced memory capacity.

Analog Input / Output Modules

• P0916TH: 8-Channel Analog Input Module; 4–20 mA HART-compatible, 16-bit resolution, for FBM (Fieldbus Module) enclosures.
• P0916TJ: 8-Channel Analog Output Module; 4–20 mA output, supports HART pass-through communication.
• P0916TB: 16-Channel Analog Input Module; high-density AI for process variable acquisition in FBM32 enclosures.
• FBM201: HART Analog Input FBM; 8-channel, supports Device Description (DD) files for smart transmitter integration.
• FBM202: HART Analog Output FBM; 8-channel AO with HART communication for control valve positioners.

Digital Input / Output Modules

• P0916SZ: 32-Channel Digital Input Module; 24 VDC, isolated, for discrete process status monitoring.
• P0916TA: 32-Channel Digital Output Module; 24 VDC sourcing output, relay-driven for solenoid and motor starter control.
• FBM211: Digital Input FBM; 16-channel, 120 VAC/VDC compatible, for high-voltage discrete inputs.
• FBM212: Digital Output FBM; 16-channel relay output, rated for 2A per channel.

Power Supply Modules

• P0922VW: I/A Series Enclosure Power Supply; 24 VDC, 20A output, redundant-capable for control enclosures.
• P0922YZ: Redundant Power Supply Module; hot-swap capable, for high-availability enclosure configurations.

Sourcing Hard-to-Find & Obsolete I/A Series Parts

The Foxboro I/A Series entered its mature/end-of-life phase for many sub-components following Schneider Electric's acquisition of Invensys (2014) and the subsequent migration push toward EcoStruxure Foxboro DCS. Original-specification modules including the P0971WV DNBT, CP40B, CP60, and legacy FBM series are no longer manufactured. DriveKNMS maintains a dedicated inventory of tested, pull-from-service I/A Series modules sourced from decommissioned plant assets globally. Our procurement network covers North America, Western Europe, the Middle East, and Southeast Asia, enabling rapid fulfillment for emergency maintenance and planned lifecycle extension projects. All modules are catalogued by revision level and firmware version where applicable, ensuring compatibility with existing installed configurations.

Quality Control for the I/A Series Range

I/A Series modules present specific test challenges due to their proprietary Nodebus backplane protocol and multi-layer PCB construction. DriveKNMS applies a structured verification process for all I/A Series inventory: (1) Visual inspection for capacitor degradation, corrosion, and connector pin integrity; (2) Powered bench test using an I/A Series test enclosure with active Nodebus segment to verify module enumeration and communication handshake; (3) For Dual Nodebus modules (DNBT), both Nodebus A and Nodebus B paths are independently tested for signal integrity and switchover response; (4) Functional I/O verification for analog and digital modules using calibrated signal sources and measurement equipment; (5) Firmware revision logging and comparison against Foxboro compatibility matrices. Modules that fail any stage are quarantined and not offered for sale.

© 2026 DriveKNMS. All trademarks belong to their respective owners. Specifications are for reference only and subject to change without notice. Verify all parameters against official documentation before installation.