Description

Honeywell CC-TFB811 Fieldbus Field Termination Assembly

Configured for field device interfacing in Honeywell Experion PKS platforms, the Honeywell CC-TFB811, also cataloged as the CC-TFB811 Fieldbus Field Termination Assembly (FTA), provides direct physical/electrical execution. It establishes the electrical connectivity between Foundation Fieldbus H1 networks and the C300 controller input/output modules (IOMs), routing individual field signals while stabilizing communication loops against external electrical interference.

Hardware Specifications

Parameter	Specification
Model	CC-TFB811
Brand	Honeywell
Part Number	51308311-175
System Compatibility	Honeywell Experion PKS, C300 Controller Series
Module Type	Fieldbus Field Termination Assembly (FTA)
Protocol Support	FOUNDATION Fieldbus H1
Number of Channels	4 or 8 Fieldbus segments (configuration dependent)
Mounting Options	Standard DIN Rail / TAPs Carrier
Operating Voltage	24 VDC
Operating Temp	-40 deg C to +70 deg C (-40 deg F to 158 deg F)
Storage Temp	-40 deg C to +85 deg C (-40 deg F to 185 deg F)
Relative Humidity	5% to 95% RH (non-condensing)
Conformal Coating	Available options for corrosive environments
Origin	Contact manufacturer for specific factory location
Weight	Contact manufacturer for exact physical specification
Dimensions	Contact manufacturer for exact physical specification
Power Consumption	Configuration dependent based on active segment load

FOUNDATION Fieldbus connectivity & Channel Isolation

The CC-TFB811 integrates dedicated physical layer components to manage FOUNDATION Fieldbus H1 network topologies directly linked to the C300 control environment. The assembly architecture implements channel-to-channel isolation parameters to prevent ground loop currents from propagating across adjacent Fieldbus segments. This galvanic isolation topology protects internal C300 digital bus electronics against field-side transient voltage surges, impedance drops, and short circuits. Furthermore, the embedded passive conditioning circuitry maintains optimal segment impedance in compliance with IEC 61158-2 physical layer profiles, ensuring signal waveform integrity and mitigating data packet loss caused by high-frequency line noise.

Frequently Asked Questions

Q: Does the CC-TFB811 support hot-swapping of field wiring during live operation?

A: The physical termination assembly uses pluggable terminal blocks that allow for rapid disconnection; however, fieldbus segments must be verified as safe, and specific control loop safety protocols must be followed to prevent network interruptions or segment dropouts on the active C300 IOM.

Q: What are the grounding requirements for the Foundation Fieldbus cable shields on this FTA?

A: Fieldbus cable shields must be grounded at a single point, typically at the FTA end or via designated TAPs carrier grounding bars, to prevent the formation of ground loops that inject noise into the communication signal.

Q: How does the CC-TFB811 handle segment power distribution?

A: The board routes 24 VDC system power to the connected fieldbus segments. The maximum current per segment is limited by the upstream Fieldbus Power Supply (FPS) and the internal trace ratings of the hardware assembly.

Field Installation Guidelines

• Mounting Orientation: Secure the unit horizontally or vertically on standard DIN rails or a proprietary TAPs carrier within an enclosed, climate-controlled cabinet. Ensure a minimum clearance of 50 mm around the assembly for adequate thermal dissipation.
• Wiring Procedures: Use wire sizes within the specified terminal block gauge limits. Strip insulation to the manufacturer-recommended length to prevent exposed conductors from creating short-circuit hazards. Torque terminal screws to specified engineering limits to ensure vibration-proof contact.
• Shield Grounding: Terminate the Fieldbus H1 cable shields to the designated instrumentation ground bus bar. Do not ground both ends of the cable shield to avoid ground potential differences.
• Power Routing: Verify that the 24 VDC input power supply is de-energized before connecting wires to the power terminals to prevent inductive arcing and component degradation.

Specifications

• Brand: Honeywell

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems