WhatsApp: +86 16626708626
Email: 
Phone: +86 16626708626Description
3. Key Technical Specifications
| Parameter | Value |
|---|---|
| Input Channels | 8 isolated thermocouple/mV channels + 1 isolated RTD reference junction channel |
| Input Range | –10.5 to +69.5 mV dc |
| Supported Thermocouples | B, E, J, K, N, R, S, T (and other mV signals) |
| Reference Junction | 4-wire 100 Ω platinum RTD (IEC 751 Class B) at termination assembly |
| Accuracy (mV) | ±0.03% of span (±24 to ±27 µV) at 25 °C |
| Thermocouple Conformity | ±0.25 °C |
| RTD Reference Accuracy | ±0.50 °C (with Foxboro TA) |
| Isolation | Channel-to-channel and channel-to-ground galvanic isolation |
| Differential Input Impedance | 10 MΩ |
| Power Consumption | 3 W maximum |
| Heat Dissipation | 3 W maximum |
| Communication | Redundant 2 Mbps Module Fieldbus |
| Operating Temperature | –20 °C to +70 °C (module) |
| Burnout Detection | Up-scale (open thermocouple detection) |
| Integration Period | Software configurable |
4. Product Introduction
The Foxboro FBM202 is an 8-channel channel-isolated thermocouple and millivolt input module for the I/A Series and EcoStruxure Foxboro DCS. It accepts standard thermocouple types (B, E, J, K, N, R, S, T) as well as low-level mV signals and includes one dedicated isolated RTD channel for cold-junction reference temperature compensation at the termination assembly.
Each channel uses an independent Sigma-Delta A/D converter, provides galvanic isolation, and includes up-scale burnout detection. The module communicates with the Field Control Processor or Fieldbus Communication Module over the redundant Module Fieldbus. It is the modern functional replacement for the legacy 100 Series FBM02 and supports the same field wiring via appropriate termination assemblies or adapters.
- FBM202
5. Troubleshooting Quick Reference
| Symptom | Possible Cause | Relevance to this Part | Quick Check Method | Recommendation |
|---|---|---|---|---|
| Channel reads open / up-scale | Open thermocouple or broken wire | ✅ High | Measure mV at termination terminals; check continuity | Verify sensor and field wiring first |
| Incorrect temperature reading | Wrong TC type configured or CJC error | ✅ High | Confirm configured thermocouple type and RTD reference | Match software setting to installed TC type |
| All channels offline | Fieldbus or power issue | ✅ High | Check Module Fieldbus status and 24 V backplane power | Confirm FCM/FCP health and redundant Fieldbus |
| High noise or unstable readings | Poor shielding or ground loop | ✅ Medium | Check cable shielding and grounding practices | Use twisted-pair shielded cable and proper grounding |
| Reference junction error | Faulty RTD on termination assembly | ✅ High | Measure RTD resistance at TA | Replace or verify termination assembly RTD |
| Module not recognized | Incorrect baseplate or seating | ❌ Low | Reseat module; verify keying and baseplate type | Confirm proper mounting and configuration |
If symptoms persist, capture module status LEDs, diagnostic logs, configured thermocouple types, and photos of the module and termination assembly, then contact technical support.
6. Frequently Asked Questions (FAQ)
Q: What thermocouple types does the FBM202 support? A: Types B, E, J, K, N, R, S, and T, plus general millivolt signals in the –10.5 to +69.5 mV range.
Q: Does it include cold-junction compensation? A: Yes. A dedicated isolated RTD channel measures the reference junction temperature at the termination assembly for accurate compensation.
Q: Is burnout detection provided? A: Yes. Open thermocouple (burnout) detection drives the reading up-scale.
Q: What is the modern replacement relationship to the older FBM02? A: The FBM202 is the 200 Series channel-isolated replacement for the legacy 100 Series FBM02. Existing field wiring can often be reused with the appropriate termination assemblies or adapters.
Q: Why is the price lower than a factory-new unit from Schneider Electric? A: This is New Original / New Surplus stock—genuine Foxboro parts that have never been installed in a running system. Units ship with a 1-year warranty after functional verification.
Q: Are the channels isolated? A: Yes. All thermocouple/mV channels and the RTD reference channel are galvanically isolated from each other and from system ground.
Q: What is the typical lead time and warranty? A: Units are normally in stock for same- or next-day shipment. All modules carry a 1-year warranty against defects in materials and workmanship.
