FBM201 RH914SQ Foxboro I/A Series Analog Input Module

Foxboro FBM201 RH914SQ I/A Series 8-Channel Analog Input Module

The Foxboro FBM201 RH914SQ, also cataloged as the FBM201 Analog Input Interface Module, operates as a dedicated hardware component for 0-20 mA DC current loop signal processing and digital conversion within Foxboro I/A Series 200 Series DCS platforms.

Suffix Breakdown & Model Matrix

Hardware Specifications

4-20 mA HART Loop Protocol & Channel-to-Channel Isolation

The FBM201 RH914SQ incorporates dedicated sigma-delta analog-to-digital converters for each of its eight input channels, achieving an analog accuracy rating of +/-0.03% of span. Galvanic isolation up to 600 VAC across channels and ground suppresses common-mode noise (>100 dB at 50/60 Hz) and prevents ground loop signal distortion. The module communicates with Fieldbus Communication Modules (FCM) or Fieldbus Processors (FCP) over a redundant 2 Mbps module fieldbus, supporting pass-through electrical compatibility for standard HART field device signals.

Frequently Asked Questions

Q: Does the FBM201 RH914SQ require routine field recalibration?

A: No. Factory laser trimming and integrated self-calibration circuits maintain analog accuracy over time, eliminating routine calibration requirements for the module and its associated termination assembly.

Q: How does the module react to accidental field wiring short circuits?

A: Normal current input stays limited to less than 30 mA per channel under standard operating conditions. If an absolute short circuit occurs, internal current-limiting protection restricts maximum loop current to approximately 100 mA to prevent hardware damage.

Field Installation Guidelines

Engineers must snap the FBM201 RH914SQ onto its compatible modular baseplate and tighten the retaining screws to ensure proper grounding through the baseplate chassis ground strip. Connect the 37-pin D-sub interface to the designated Foxboro Termination Assembly (TA) via factory-approved shielded cables not exceeding 30 m in total length. Ensure that all field cable shields terminate at a single earth ground bar inside the cabinet entry point to prevent high-frequency noise from corrupting 0-20 mA sensor measurements.