Description
Foxboro FBM216B RH927AJ Product Page
Product Overview
The Foxboro FBM216b RH927AJ is a redundant-ready HART communication input module for Foxboro I/A Series and Foxboro DCS installations. It provides eight individually isolated analog input channels, each accepting a standard 4–20 mA signal or a compatible HART signal superimposed on that current loop. The module converts the analog input into digital values for the control system while supporting communication with compatible smart field instruments. Typical applications include pressure, flow, level, and temperature transmitters that provide current-loop outputs and digital instrument data.
Each input channel has a dedicated HART frequency-shift-keying modem, supporting bidirectional digital communication with a field device. The module supports HART versions 5, 6, and 7 and uses point-to-point, asynchronous, half-duplex communication at 1200 baud. The system can request and receive up to two digital messages per second from each field device, subject to controller loading and configuration. Analog input conversion uses sigma-delta technology, with a new input value available every 100 milliseconds. The specified analog accuracy is ±0.075% of full scale, including nonlinearity, with 15-bit resolution. Each channel has galvanic isolation from other channels, ground, and module logic.
For maintenance teams, the Foxboro FBM216b RH927AJ is particularly useful where instrument availability matters and a single module failure should not interrupt field measurement. Two modules can be configured as a redundant pair, with one operating as Master and the other as Tracker. Both receive the field input signals through a common termination assembly and redundant adapter. If one module fails, the other can continue receiving the input signals, subject to correct configuration and system health. Replacement planning should include the RH924DT redundant adapter, compatible termination assembly, termination cable, loop-power arrangement, and controller software requirements. Verify the complete hardware configuration before commissioning; the module part number alone does not establish that the existing wiring and redundancy arrangement are suitable.
Product Introduction — Instrumentation and Reliability Focus
A transmitter signal may remain electrically valid even when digital instrument diagnostics are no longer available. The Foxboro FBM216b RH927AJ supports eight isolated 4–20 mA input loops with HART communication, allowing the control system to read process values and request supported data from compatible smart instruments.
For replacement work, verify the termination assembly, redundant adapter, loop-power source, and HART device compatibility. Test both the analog measurement and digital communication after installation, particularly when the module is part of a redundant input pair.
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Model | FBM216b |
| Part number | RH927AJ |
| Previous part number | P0927AJ |
| Manufacturer | Foxboro / Schneider Electric |
| Product type | Redundant HART communication analog input module |
| Input channels | 8 individually isolated channels |
| Analog input range | 4–20 mA DC |
| HART compatibility | Versions 5, 6, and 7 |
| HART communication | Point-to-point, asynchronous, half-duplex |
| HART baud rate | 1200 baud |
| Digital message rate | Up to 2 messages per second per field device |
| Analog input accuracy | ±0.075% of full scale, including nonlinearity |
| Input resolution | 15 bits |
| Input update rate | 100 ms |
| Sense resistor | 280 Ω ±0.02% |
| Nominal input resistance | 280 Ω, including redundant adapter |
| Internal loop supply | Isolated 24 VDC ±10% per channel |
| Minimum compliance voltage | 18.5 VDC at 20.5 mA at the termination assembly |
| Module supply | 24 VDC, +5%/−10% |
| Maximum power consumption | 8.7 W |
| Maximum heat dissipation | 5.6 W |
| Fieldbus | Redundant 2 Mbps module fieldbus |
| Redundant adapter | RH924DT |
| Termination assembly | RH924JH for the compact FBM216b arrangement; confirm the assembly appropriate to the installed module format |
| Termination cable length | Up to 30 m, depending on cable type |
| Operating temperature | −20°C to +70°C |
| Storage temperature | −40°C to +70°C |
| Relative humidity | 5–95%, non-condensing |
| Mounting | Modular baseplate; DIN rail or 19-inch rack with suitable mounting hardware |
| Module dimensions | 102 mm high; 114 mm including mounting lugs × 45 mm wide × 140 mm deep |
| Module weight | Approximately 284 g |
Important: Confirm whether the installed system uses the standard 200 Series FBM216b or a Compact FBM216b arrangement. The required termination assembly differs by hardware format.
FBM216B-RH927AJ
Related Products
- FBM214b RH927AH: Eight-channel HART input module for applications that do not require the FBM216b redundant-ready arrangement.
- FBM218 RH922VW: Eight-channel redundant-ready HART analog output module; it drives field devices rather than reading input signals.
- FBM215 RH922VU: Eight-channel HART analog output module for compatible Foxboro DCS installations.
- FBM244 RH927AK: Four-input/four-output analog I/O module with HART support; channel configuration differs from the FBM216b.
- RH924DT: Redundant adapter specified for the standard FBM216b module.
- RH924JH: Termination assembly listed for the Compact FBM216b arrangement.
- RH916DC: 3 m polyurethane termination cable option for compatible standard termination assemblies.
- RH928AD: 3 m low-smoke, zero-halogen cable option for compatible arrangements.
- RH903SV: Four-channel cable balun module used where multiple HART loops share an external power supply, according to the approved wiring design.
- FCP280: Foxboro control processor used in supported DCS architectures; it handles controller functions rather than field signal termination.
Related components are not automatically interchangeable. Match the exact module format, termination assembly, adapter, cable, and field-power arrangement before ordering.
Frequently Asked Questions
Q1. What is the Foxboro FBM216b RH927AJ used for?
It acquires eight analog current signals from compatible field transmitters and supports HART communication with smart instruments. It is used in Foxboro DCS installations where both process-variable measurement and digital instrument access are required.
Q2. Is the FBM216b an analog output module?
No. It is an analog input module. For HART-capable output loops, the FBM218 or FBM215 may be relevant, depending on the required redundancy and system configuration.
Q3. Does the FBM216b support HART 7?
Yes. The official product specification lists HART versions 5, 6, and 7. Actual access to device-specific parameters depends on the instrument’s HART implementation and the DCS software tools in use.
Q4. How does redundancy work with the FBM216b?
Two modules operate as a Master/Tracker pair and receive the same field input signals through a common termination assembly and redundant adapter. If one module fails, the healthy module can continue processing the input signals, assuming the redundancy configuration and associated hardware are operating correctly.
Q5. Can I hot-swap the FBM216b?
The manufacturer documents that either module in a redundant pair can be removed or replaced without disturbing the field input signals handled by the healthy module. Even so, follow the site’s approved maintenance procedure, confirm which module is Master or Tracker, and verify the system status before removal.
Q6. Which redundant adapter and termination assembly are required?
For the standard FBM216b, the documented redundant adapter is RH924DT. The termination assembly and cable must match the installed hardware format. Compact FBM216b systems use a different termination arrangement, so verify the baseplate and module type before purchasing accessories.
Q7. Can a shared external loop supply affect HART communication?
Yes. When a common external supply powers two or more HART loops, Schneider Electric specifies a cable balun arrangement to help prevent communication crosstalk. Loops powered by the module’s internal isolated supplies do not require cable baluns for this reason.
Q8. What should procurement verify for a refurbished ?
Check the module label, connector condition, hardware revision where applicable, and evidence of functional testing. Request confirmation that all eight analog channels and HART communication have been checked. For redundant installations, verify the RH924DT adapter, termination assembly, cable, warranty, and return terms as separate line items where necessary.
