Foxboro FBM203 Foundation Fieldbus Analog Input Module

Functional Features:

• Provides 8 analog input channels with 4–20 mA input capability
• Supports HART 5/7 communication on each channel for smart transmitter access
• Includes per-channel signal filtering (configurable: 0.5 s to 10 s)
• Supports per-channel range scaling (e.g., 0–100 psi, 0–500°C)
• Provides diagnostic data including wire fault detection, sensor fault, and out-of-range alarms
• Features galvanic isolation between each input channel and the Fieldbus
• Supports FOUNDATION Fieldbus function blocks for in-segment signal processing

Technical Specifications:

• Number of Channels: 8 analog inputs
• Input Signal: 4–20 mA DC (2-wire loop powered)
• Input Resistance: 250 Ω maximum (voltage drop at 20 mA = 5 VDC)
• Resolution: 16-bit A/D converter (65,536 counts)
• Accuracy: ±0.1% of calibrated span (typical)
• HART Protocol: HART 5 and HART 7 compliant on all channels
• Scan Rate: 1 second per channel (typical), configurable down to 100 ms
• Isolation: 500 VDC between channels, 500 VDC to Fieldbus
• Common Mode Rejection: ≥ 100 dB at 50/60 Hz
• Power Supply: 24 VDC from FBM chassis backplane (via FBM201 or equivalent)
• Operating Temperature: 0°C to +60°C (+32°F to +140°F)
• Module Format: Standard FBM series half-width card
• Dimensions: Standard FBM card (approx. 165 mm × 100 mm × 25 mm)

Material Composition:

• PCB: FR-4 fiberglass epoxy with conformal coating
• Connectors: Shielded Fieldbus connector (Type A) + screw-terminal blocks for field wiring
• Housing: Metal shield with EMI gasket
• Terminal Blocks: Phoenix Contact or equivalent, rated for 1.5 mm² to 2.5 mm² wire

Applicable Industries:
Oil and Gas, Chemical Processing, Power Generation, Refining, Pharmaceutical, Food and Beverage, Pulp and Paper

Installation Requirements:

• Installed in FBM series chassis with FBM201 power supply (or equivalent)
• Field wiring (4–20 mA loops) connected to screw-terminal blocks on the module
• Fieldbus trunk cable connected via shielded twisted pair (Type A)
• Configuration via I/A Series Control Builder or Evo DCS engineering software
• HART communication requires a HART modem or multi-drop HART master

Advantages:

• 8 channels per module reduces chassis space and cost
• HART on every channel enables full smart transmitter diagnostics without additional hardware
• High-resolution 16-bit conversion provides excellent measurement accuracy
• Per-channel isolation prevents ground loops and crosstalk between inputs