Foxboro FBM26A/27A Product Description

The Foxboro FBM26A/27A is a high‑density, channel‑isolated discrete output expansion module within the Foxboro I/A Series™ and EcoStruxure Foxboro DCS (Schneider Electric) Compact 200 Series. Engineered as an enhanced external‑powered digital output card, it delivers robust on/off control for field devices across process industries. Optimized for full channel‑to‑channel galvanic isolation, multi‑voltage external excitation, expanded diagnostic capabilities, and G3 harsh‑environment resilience, the FBM26A/27A ensures dependable switching for solenoids, motor starters, contactors, lamps, and alarm beacons. Supporting hot‑swap, redundant communication, and comprehensive fault monitoring, it is ideal for high‑availability control in chemical, oil and gas, power, and water treatment applications. As an upgraded member of the 200 Series, it builds on the FBM26 platform with enhanced ruggedness and diagnostic depth for critical process expansions.

The FBM26A/27A provides 16 fully galvanically isolated discrete output channels, with each channel electrically separated from adjacent channels and ground, boasting a withstand rating of 600 V AC for one minute. This design eliminates ground loops, minimizes electrical noise, and prevents cross‑channel interference—critical for systems relying on external power sources. All channels support external‑only sourcing, meaning the module does not supply field power and operates with customer‑provided 15–60 VDC, 120 VAC/125 VDC, or 240 VAC supplies.

Each output channel is rated for 2 A continuous current (2.25 A maximum) at 60 VDC, with an inrush capacity of 8 A for 20 ms at 30°C, suitable for inductive loads like relays and solenoids. The on‑state voltage drop is ≤ 0.2 V at full load, and off‑state leakage current is ≤ 0.1 mA, ensuring clean switching and minimal power loss. Outputs are solid‑state, normally open switches with configurable fail‑safe modes: users can preset outputs to hold the last state or de‑energize on communication loss or fault.

The module executes discrete I/O or ladder logic programs with configurable parameters including input filtering time, fail‑safe rollback, and continuous or transient output modes. Designed for high availability, it supports hot‑swap installation and replacement, enabling online maintenance without process shutdown. Communication with Foxboro FCP/ZCP controllers uses a redundant 2 Mbps HDLC fieldbus, providing error‑checked data transfer with automatic path failover. Onboard LED indicators display power, communication status, and individual channel state (active/fault), allowing quick on‑site troubleshooting. Enhanced diagnostics monitor channel health, communication integrity, power supply status, and load anomalies, reporting detailed faults to the DCS in real time.

Constructed with a rugged, conformal‑coated PCB and heavy‑duty industrial housing, the FBM26A/27A is certified for ISA S71.04 Class G3 harsh environments (dust, moisture, vibration, and corrosive atmospheres). It operates reliably in extended temperature ranges and supports 24 VDC redundant power input with automatic failover for maximum uptime.

Manufacturer: Foxboro (Schneider Electric)Compatible Systems: Foxboro I/A Series DCS (v7.0+), EcoStruxure Foxboro (Foxboro Evo™) DCSModel/Part Number: FBM26A/27AModule Type: 16‑channel externally sourced discrete output expansion module (16DO)Output Channels: 16 fully galvanically isolated channels; channel‑to‑channel and channel‑to‑ground isolationExternal Voltage Ranges: 15–60 VDC, 120 VAC / 125 VDC, 240 VACContinuous Current Rating: 2 A per channel (2.25 A maximum) at 60 VDC; 0.5 A per channel at 240 VACInrush Current: 8 A for 20 ms at 30°COn‑State Voltage Drop: ≤0.2 V at 2.25 AOff‑State Leakage Current: ≤0.1 mAIsolation Withstand: 600 V AC for 1 minute (channel‑to‑channel/ground)Communication: Redundant 2 Mbps HDLC fieldbus (to FCP/ZCP controllers)Power Supply: 24 VDC (+5%/–10% tolerance), redundant input supported; no internal field powerPower Consumption: Max 10 W; typical 8 WOperating Temperature: –20 °C to +70 °CStorage Temperature: –40 °C to +85 °CRelative Humidity: 5%–95% non‑condensingVibration: 0.05 g rms, 5–500 HzShock: 5 g, 20 ms half‑sineAltitude: –300 m to +3,000 mEnclosure: Heavy‑duty industrial housing, conformal‑coated PCB; IP20 ratingDimensions (W × H × D): Approximately 45 mm × 114 mm × 104 mmWeight: Approximately 0.35 kgCertifications: CE, UL, CSA, ATEX Zone 2, IECEx, ISA S71.04 Class G3; EMC Class A (IEC 61000‑6‑2)Reliability: MTBF > 100,000 hours; hot‑swap capable; redundant communication and power support; full channel isolation for noise immunity; enhanced diagnostic coverage.

The FBM26A/27A is ideal for high‑density discrete control requiring external excitation, full channel isolation, and enhanced diagnostics in space‑limited panels, suited for medium‑to‑large‑scale systems and critical plant expansions. In chemical and petrochemical plants, it drives solenoid valves, valve actuators, and burner ignition relays powered by 120/240 VAC external sources, supporting batch and continuous process control with minimal electrical interference.

In oil and gas facilities—including refineries, offshore platforms, and gas processing plants—it controls safety shutdown valves, wellhead actuators, and flare ignition systems operating at 240 VAC, ensuring reliable operation in hazardous areas with high noise immunity.

In power generation, the module manages breaker trip coils, turbine latching relays, and boiler purge valves using 125 VDC external power, supporting safe startup, shutdown, and emergency trip functions with fast fault detection.

In water and wastewater treatment, it controls dosing pumps, aeration blowers, and motorized valves with 15–60 VDC external excitation, enabling precise process control and regulatory compliance.

In pharmaceutical, food and beverage, and general manufacturing, its compact size, full channel isolation, multi‑voltage compatibility, and enhanced diagnostics make it perfect for panel‑side I/O consolidation, machine interlocking, and alarm beacon control in both hygienic and harsh environments.

The FBM26A/27A mounts on standard DIN rails or horizontally on a Compact 200 Series backplane inside Foxboro I/A Series or EcoStruxure Foxboro cabinets, connecting to a dedicated baseplate for backplane power and redundant HDLC fieldbus communication. Field wiring terminates at a mating termination assembly (TA) equipped with screw terminals, per‑channel fuses, and knife disconnect/test sockets for maintenance. TAs support local/remote wiring and accommodate 15–60 VDC, 120 VAC/125 VDC, or 240 VAC external power, with options for relay outputs, solid‑state switching, and power distribution fusing.

Configuration is performed via Foxboro DCS software: set output fail‑safe states (hold or off), map channels to DCS tags, enable redundant communication/power, and configure fault reporting parameters. The module is plug‑and‑play compatible with existing Foxboro systems and supports hot‑swap replacement to minimize downtime.

For high availability, two FBM26A/27A modules can be configured as a redundant pair with automatic fault detection and switchover, ensuring seamless control continuation if one module fails. It supports integration with up to 128 200 Series FBMs in a single system, making it suitable for large‑scale plant expansions.

Routine maintenance includes visual inspection for physical damage, loose connections, or dust buildup, and verification of front‑panel LEDs for normal power, communication, and channel status. Periodic testing of output switching performance, load capacity, and redundant failover is recommended, especially in high‑vibration or corrosive environments.

The conformal coating protects against moisture and dust, reducing cleaning frequency. Faulty modules can be repaired by authorized Schneider Electric service providers, with standard and expedited repair options available.

The FBM26A/27A comes with a 12‑month standard warranty against manufacturing defects, with extended warranty options available for long‑term operational reliability.