Foxboro FBM239 Product Description

The Foxboro FBM239 (part number P0927AG) is a high-density 16-channel discrete input / 16-channel discrete output (16DI/16DO) module for the Foxboro I/A Series and EcoStruxure Foxboro DCS, manufactured by Schneider Electric. It serves as a compact, rugged interface between the DCS and field-side on/off devices—such as limit switches, proximity sensors, motor starters, solenoid valves, and alarm beacons—delivering reliable signal acquisition and switching control in critical process environments. Designed for high availability and ease of integration, the FBM239 combines high channel count with robust electrical isolation, onboard diagnostics, and support for redundant operation, making it ideal for high–I/O-density cabinets and harsh industrial applications.

The FBM239 provides 16 fully isolated digital input channels and 16 fully isolated digital output channels, offering a high–density, cost-effective solution for discrete control. Inputs accept a wide range of DC voltage levels, with logic zero defined as −0 to 10 VDC and logic one as 33 to 150 VDC, enabling compatibility with both low-voltage and high-voltage field sensors. Each input channel includes noise filtering and debounce logic to ensure stable detection in electrically noisy environments.

The 16 digital outputs are voltage-monitored switch-type outputs rated for an external source of up to 150 VDC. Each channel supports a maximum current of 2 A with an on-state resistance of 1 kΩ, and can handle surge currents up to 20 A for 20 ms, suitable for driving inductive loads such as relays and contactors. Outputs feature short-circuit protection with indefinite short-circuit endurance under duty-cycle limiting, enhancing operational safety.

Built-in 2500 V RMS galvanic isolation separates all input channels, output channels, and the backplane, eliminating ground loops and protecting the module and DCS from electrical transients and noise. The module supports hot-swap capability, allowing online replacement without shutting down the process, which minimizes downtime during maintenance.

Communication with the Foxboro DCS controller (FCP/ZCP) is via a redundant 2 Mbps HDLC fieldbus, ensuring continuous, error-resistant data exchange. Onboard LED indicators provide clear visual status for power, communication link, and individual channel activity/faults, enabling fast on-site diagnostics. Advanced built-in diagnostics continuously monitor channel status, communication health, and power supply, and report faults to the DCS in real time for proactive maintenance.

The FBM239 features a compact, rugged design with a conformal-coated PCB and a durable housing, rated for ISA S71.04 Class G3 harsh environments (dust, moisture, vibration). It supports redundant 24 VDC power input for enhanced reliability, with automatic failover in case of power supply failure.

Manufacturer: Foxboro (Schneider Electric)Compatible Systems: Foxboro I/A Series DCS (v7.0+), EcoStruxure Foxboro (Foxboro Evo™) DCSModel/Part Number: FBM239 (P0927AG)Module Type: 16-channel discrete input / 16-channel discrete output (16DI/16DO)Digital Inputs: 16 channels, isolated; logic zero: −0 to 10 VDC, logic one: 33 to 150 VDCDigital Outputs: 16 channels, isolated voltage-monitored switches; max 150 VDC external source, 2 A per channel, 1 kΩ max on-state resistanceIsolation: 2500 V RMS channel-to-channel, channel-to-backplane (1-minute withstand)Communication: Redundant 2 Mbps HDLC fieldbus (to FCP/ZCP)Power Supply: 24 VDC (+5%/–10% tolerance), redundant input supportedPower Consumption: Max 7 W; typical 4 WOperating Temperature: –20 °C to +70 °C (standard); –40 °C to +70 °C (extended)Storage Temperature: –40 °C to +85 °CRelative Humidity: 5%–95% non-condensingAltitude: –300 m to +3,000 mEnclosure: Rugged housing, conformal-coated PCB; IP20 ratingDimensions (W × H × D): Approximately 49 mm × 99 mm × 72 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

The FBM239 is widely used in process industries requiring high-density discrete I/O and reliable on/off control. In chemical and petrochemical plants, it monitors limit switches and position indicators on valves, reactors, and conveyors, while driving solenoid valves, motor starters, and alarm systems for safe and efficient batch and continuous processes.

In oil and gas facilities—including refineries, offshore platforms, and gas processing plants—it interfaces with wellhead sensors, pressure switches, and safety shutdown devices, providing critical on/off signal monitoring and control in hazardous areas with high noise immunity.

In power generation, the FBM239 handles interlock switches, breaker status inputs, and auxiliary relay outputs for boilers, turbines, and balance-of-plant systems, supporting safe and reliable plant operation with fast fault detection.

In water and wastewater treatment, it monitors level switches, flow switches, and pump status signals, and controls dosing pumps, valves, and aeration equipment, ensuring precise, compliant process control.

In pharmaceutical, food and beverage, and general manufacturing, its compact size, high channel count, and robust isolation make it ideal for panel-side I/O consolidation, machine interlocking, and alarm management in both hygienic and harsh industrial environments.

The FBM239 mounts on standard DIN rails in Foxboro I/A Series or EcoStruxure Foxboro cabinets, attaching to a dedicated baseplate for backplane power and redundant HDLC fieldbus communication. Field wiring connects to a termination assembly (TA) with screw terminals and optional surge protection; the TA supports both local and remote field wiring and can be equipped with output bypass switches for maintenance without process interruption.

Configuration is performed via Foxboro DCS software: set input logic levels, configure output fail-safe states (hold last value or off), map I/O channels to DCS tags, and enable redundant communication and power operation. The module is plug-and-play compatible with existing Foxboro systems and supports hot-swap replacement for minimal downtime.

For high availability, two FBM239 modules can be configured as a redundant pair with automatic fault detection and switchover, ensuring seamless control continuation in case of module failure.

Routine maintenance includes visual inspection for physical damage, loose connections, or dust accumulation, and verification of front-panel LED indicators for normal power, communication, and channel status. Periodic testing of input accuracy, output switching performance, 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 FBM239 comes with a 12-month standard warranty against manufacturing defects, with extended warranty options available for long-term operational reliability.