Foxboro FBM211 P0914TN Discrete Input Module

Channel Quantity: Typically 16 discrete input channels, supporting simultaneous monitoring of multiple switching signals.

Input Types:
Compatible with multiple voltage levels (e.g., 24V DC, 120V AC, etc., subject to model configuration).
Supports dry contacts (passive contacts) or wet contacts (active signals) input.

Signal Conditioning:
Input signals first pass through a filter circuit to remove interference, then are converted by a level conversion circuit from field signals (e.g., 24V DC switching quantities) to standard levels (e.g., 5V DC) processable by the module.

Isolation Technology:
Each input channel uses optoelectronic isolation or current isolation technology (isolation voltage typically >2500Vrms) to prevent field interference from affecting system stability and avoid module failures impacting field devices.

Conditioned switching signals (high/low levels) are converted to digital signals (0 or 1) via an analog-to-digital conversion circuit (ADC) and temporarily stored in the module's internal registers.

The built-in microprocessor (MCU) samples, caches, and preliminarily processes digital signals (e.g., debouncing, signal validity verification).

Communication Protocol: Connects with controllers (e.g., CP series) via FOUNDATION Fieldbus H1 or other dedicated buses (e.g., Foxboro internal bus) at a transmission rate of typically 31.25kbps.

Data Transmission:
The module periodically packages input channel statuses (register data) and sends them to the controller to update field device statuses.
Receives configuration commands (e.g., input filtering time, fault thresholds) from the controller to adjust working parameters.

Supports single-module or redundant configuration (e.g., dual-module hot standby), automatically switching to the standby module when the main module fails to ensure uninterrupted data collection.

Communication links can be configured in redundant modes (e.g., dual-bus connection) to enhance system fault tolerance.

The module integrates a watchdog circuit and power monitoring module to real-time monitor:
Abnormal input signals (e.g., open circuit, short circuit, voltage overrun);
Internal circuit failures (e.g., damaged isolation components, power voltage fluctuations);
Communication link interruptions or data check errors (CRC check).

Upon detecting faults, the module alarms via indicator lights (e.g., LEDs), writes fault information to the event log, and reports to the control system via the communication bus.

Some models support a "fail-safe" mode (e.g., defaulting to a safe output state during input faults) to prevent equipment misoperation due to signal anomalies.

Industrial production lines: Monitoring limit switches and safety door status, triggering shutdown protection.

Power systems: Collecting on/off states of circuit breakers and disconnectors.

Process control: Detecting level switch and pressure switch signals for process logic control.

Input voltage range: e.g., 24V DC ±10%, 120V AC ±15%, etc.

Response time: Typical 1-10ms (depending on filtering time settings).

Environmental adaptability: Operating temperature -40°C to +85°C, supporting G3-level anti-corrosion environments.