Product Description

The FBM41 (P0902XA) is a legacy 100 Series analog interface designed for the Foxboro I/A Series distributed control system. This module integrates four analog input channels and four analog output channels in a single unit, providing efficient control loop management. It is engineered to process 0 to 20 mA signals, making it compatible with a wide range of industrial sensors, transmitters, and final control elements such as valve positioners.

As part of the rugged 100 Series, the FBM41 is built to withstand industrial environments while maintaining high signal precision. Its architecture ensures galvanic isolation between field-side signals and internal system logic, protecting the DCS from electrical interference. The module is essential for facilities maintaining or extending the lifecycle of existing Foxboro control infrastructure.

Technical Specifications

Application Scenarios

The FBM41 (P0902XA) is widely used in localized process control tasks such as:

• Level Control Loops: Receiving tank level sensor data while outputting control signals to discharge pump VFDs.

• Thermal Management: Monitoring temperature transmitters and driving steam valve actuators in heat exchangers.

• Legacy System Support: Direct replacement for aging I/A Series hardware to ensure continued plant operation.

• Small-Scale Utility Control: Managing HVAC or water treatment subsystems where combined inputs and outputs are needed in a single slot.

Frequently Asked Questions

Q: How does this module communicate with the system?
A: The FBM41 connects to the Foxboro Fieldbus via a dedicated 100 Series baseplate. It communicates with the Fieldbus Processor (FBP), which manages data exchange between the I/O modules and control stations.

Q: Can specific channels be configured for 4-20 mA instead of 0-20 mA?
A: Yes. While the hardware supports 0-20 mA, Foxboro software allows configuration of 4-20 mA. In this case, 4 mA is treated as 0% and 20 mA as 100% for process variables and control outputs.