Model Foxboro FBM237
Module Type Analog Input (AI)
Number of Channels 8 independently configurable input channels.
Input Types (Configurable) • 4-20 mA DC (current loop)
• 0-10 V DC (voltage)
• 1-5 V DC (voltage)
• Thermocouple (T/C) types (e.g., J, K, T, E, R, S, B, N)
• RTD (e.g., 100 Ohm Pt, 10 Ohm Cu)
• Millivolt (mV) signals
Resolution 16-bit (high resolution for precise measurement).
Accuracy ±0.05% of reading for voltage/current inputs. Varies for T/C and RTD based on type and range.
System Compatibility Foxboro I/A Series DCS. Must be installed in a compatible FBM fieldbase (e.g., FBM200 series).
Update Rate Configurable, typically a scan of all channels within tens of milliseconds.
Input Impedance > 1 MΩ for voltage inputs. 250 Ω (or other shunted resistor) for current inputs.
Power Supply Powered by the fieldbase (typically ±12V and +5V from the power supply module).
Isolation Channel-to-Channel: Yes, channels are isolated from each other.
Channel-to-Bus: 500 V AC optical isolation protects the system bus from field-side faults.
Field Wiring Field wiring is terminated to a removable screw terminal block on the associated fieldbase. A common return terminal is provided for groups of inputs.
Diagnostics Includes comprehensive internal diagnostics for faults (e.g., module failure, open input circuit, over-range, under-range).
LED Indicators Module status LEDs (e.g., OK, ACTIVE, FAIL) and often per-channel status indicators for faults.
Environmental Designed for industrial environments. Operating temperature typically 0 to 60°C (32 to 140°F).
The Foxboro FBM237 is a High-Density (8-channel) Analog Input (AI) module for the Foxboro I/A Series distributed control system (DCS). It is a crucial component within the FBM (Fieldbus Module) family, providing the primary interface for reading analog signals from field instruments into the digital control system.