FOXBORO FBM201 Fieldbus Module

Overview

Core Technical Specifications

1. Analog Channel Parameters

• Channel count: 8 fully galvanically isolated independent AI channels
• Standard signal range: 0–20mA DC (4–20mA industry standard transmitters)
• A/D conversion: Per-channel Sigma-Delta high-precision conversion, 16-bit resolution
• Static accuracy: ±0.03% full scale; temperature coefficient ≤50ppm/℃
• Isolation strength: 600V AC 1min withstand between channel-channel / channel-ground
• Input impedance: 61.5Ω; built-in per-channel current limiting protection (<40mA)
• Filter function: Software configurable integration time, 50/60Hz power frequency interference suppression >100dB CMRR
• HART compatibility: Support HART 7 digital communication, read transmitter tag, range, diagnostic data via DCS or handheld communicator
• Loop power supply: Terminal base provides 24VDC excitation for two-wire transmitters

2. Electrical & Communication

• System power supply: 18–32VDC, typical power consumption 4.5W
• Internal bus: Dual redundant 2Mbps proprietary I/A fieldbus, hot-swappable module
• Status indicators: Per-channel signal activity LED; Module OK green indicator, Fault red alarm LED
• Redundant I/O support: Two FBM201 modules can form redundant acquisition pair for critical process control loops

3. Mechanical & Environmental

• Mounting: Plug-in rack module, snap onto RH914SQ terminal base
• Housing: Extruded aluminum alloy, conformal coated PCB for G3 harsh industrial environment
• Dimensions: 120 × 130 × 32 mm, net weight ~0.2kg
• Operating temperature: 0℃ ~ +60℃; storage -40℃ ~ +85℃
• Humidity: 5%–95% RH non-condensing
• Protection grade: Module IP40, terminal base IP20 (cabinet internal use only)
• Certifications: CE, UL, FM Class I Div 2 hazardous area, RoHS compliant

Main Functions

1. Universal process analog signal collection

    

   Receive 4–20mA signals from pressure/differential pressure transmitters, liquid level transmitters, flow transmitters, temperature transmitters, convert analog current to digital values and upload to DCS controller for closed-loop regulation, monitoring and alarming.
2. HART intelligent device remote management

    

   Superimposed HART bus can read transmitter calibration range, sensor temperature, zero drift, blockage fault alarms without additional HART interface modules.
3. Strong anti-interference stable measurement

    

   Independent channel isolation avoids single loop short-circuit, surge interference affecting all channels; high common-mode rejection eliminates interference from inverters, servo and high-power equipment.
4. Configurable signal filtering & rate-of-change alarm

    

   Adjust digital filter time to suppress signal jitter; set upper/lower rate-of-change limits to trigger abnormal process fluctuation pre-alarm on HMI.
5. Complete self-diagnosis & fault upload

    

   Detect channel open circuit, transmitter short circuit, module bus communication failure; upload fault codes and abnormal channel numbers to DCS for remote maintenance prompt.
6. Redundant high-reliability signal acquisition

    

   Dual-module hot standby configuration for critical safety loops, single module failure will not interrupt process variable monitoring.

Advantages

• 8-channel high-density design, saves DCS rack slot space compared with 4-channel AI modules
• Per-channel independent isolation, fault isolation design reduces unplanned downtime
• Native HART support, integrated intelligent transmitter management without extra hardware
• Ultra-high conversion accuracy, suitable for precision flow, liquid level and pressure control loops
• Spring-clamp terminal base eliminates screwdriver wiring, improves cabinet assembly efficiency
• Hot-swap online replacement, no system shutdown required for module maintenance
• G3 anti-corrosion PCB, stable long-term operation in chemical plant, power plant oil mist, high humidity environment
• Perfect matching with Foxboro I/A Series & Foxboro Evo DCS, unified engineering tool configuration