Foxboro P0926JM (Internal Board for FBM231/FCM) B-Position Interface

Product Overview

The P0926JM is the core internal hardware assembly (PCBA) for the FBM231 Discrete I/O Module and various FCM (Fieldbus Communication Modules) within the Foxboro I/A Series system.

Unlike a complete encased module, the P0926JM represents the internal electronic backbone. It is specifically engineered to interface with the B-Position slot on Foxboro Modular Baseplates (such as the RH924YF and P0926KE). This component is essential for repair and maintenance, allowing technicians to restore module-to-backplane communication without replacing the entire module housing or baseplate infrastructure.

Technical Configuration

• Core Function: Provides the high-speed 32-channel discrete signal routing and bus interface logic.

• B-Position Logic: Specifically designed to occupy the B-Position within the modular baseplate architecture, managing the primary/redundant data path.

• Optical Isolation: Integrated 1500 V AC galvanic isolation to protect the DCS control network from field-side electrical surges.

• Environmental Protection: Features ISA-S71.04 Class G3 conformal coating (as visible on the board surface), ensuring maximum resistance to corrosive industrial gases ($H_2S$, $SO_2$, etc.).

Technical Specifications

Technical FAQs

Q1: Is the P0926JM a complete Field Bus Module?

A1: No. It is the internal electronic assembly (PCBA) found inside FBM231. This listing is for the bare board as shown in the photos, used primarily for hardware-level repairs.

Q2: What does "B-Position" mean in the title?

A2: On a Foxboro Modular Baseplate, the modules must connect to specific internal bus positions. The P0926JM is the hardware interface that physically and logically connects to the B-Position pins.

Q3: Can I use this to repair a failed FBM231?

A3: Yes. This is the most cost-effective way to fix a module with internal electronic failure while reusing your existing plastic housing and handles.

Engineering & Installation Guide

• Replacement Protocol: Swapping the P0926JM should be done in an ESD-safe environment. The board fits precision-keyed slots within the FBM/FCM housing.

• Redundancy Note: Ensure the partner module in redundant pairs is healthy before performing an internal board swap to maintain process continuity.

• Visual Inspection: The high-quality G3 coating on this P0926JM ensures it can be deployed in harsh "near-process" cabinets.