2. Model Definition

51204172: Base part number for 8-channel analog output FTA

-125: Conformal coated PCB hardware revision

Matched IOP Card: MC-TAOY22 (8-point analog output module)

Not interchangeable with DI, DO, HLAI, LLAI FTA series

3. Technical Specifications

Channel Quantity: 8 independent analog output channels

Output Signal: Standard 4–20mA current signal

PCB Protection: Conformal coating, flammability UL94 V0

Terminal Type: Compression screw terminals, wire size up to 14 AWG (1.6 mm²)

Form Factor: Standard Size B, length 307 mm

Mounting: Snap-on installation for 35 mm DIN rail

Operating Ambient Temperature: 0 ℃ ~ +60 ℃ (indoor control cabinet only)

Circuit Design: Passive structure with RC EMI filtering and per-channel overload protection

Redundancy: Supports dual redundant MC-TAOY22 IOP configurations

Approximate Weight: ~0.32 kg

4. Interface & Communication Configuration

Inner IOP Connection: Dedicated flat ribbon cable connector directly plugs into MC-TAOY22 IOP card. No independent communication chip; control signals transmit via UCN control bus through matched AO IOP module.

Outer Field Terminals: Polarity-marked positive/negative terminal blocks for each output loop, arranged for orderly field wiring.

Power Supply: Cabinet 24VDC system power provides reference potential for output signal loops.

5. Core Functions

Cable strain relief protects delicate pin headers of MC-TAOY22 card from damage caused by tension of field control cables.

Built-in RC EMI filters suppress industrial electromagnetic interference to stabilize 4–20mA output signals to valve positioners, variable regulators and other field actuators.

Per-channel overload protection limits abnormal current to avoid burnout of AO card under field short-circuit conditions.

Conformal coating resists moisture, dust and mild corrosion to extend service life in humid cabinet environments.

Standardized terminal layout simplifies commissioning, loop calibration, wiring inspection and fault troubleshooting.

Compatible with HART-enabled valve positioners for digital tuning and diagnostic functions alongside analog 4–20mA control.

6. Application Scenarios

Process industries with Honeywell Experion PKS UCN/C300 DCS: petrochemical, chemical, thermal power, oil & gas, pulp & paper, metallurgy, water treatment.

Control loops for regulating valves, electric actuators, variable-speed regulators receiving 4–20mA command signals.

Standard matched terminal assembly for 8-point analog output slots in DCS I/O cabinets.

7. Operation & Maintenance Instructions

Matching Restriction: Only compatible with MC-TAOY22 AO IOP card; cannot substitute digital I/O or analog input FTA boards.

Wiring Standards: Strictly follow positive/negative polarity labels; use shielded control cable with single-point shield grounding at cabinet side to reduce signal noise.

Spare Part Interchangeability: 51204172-125, 51204172-100 and 51204172-175 share identical electrical performance for on-site emergency replacement; same suffix model is preferred for long-term stable operation.

Fault Troubleshooting Flow: Abnormal/no output signal → Retighten terminal screws → Measure loop output current → Inspect ribbon cable connection status → Diagnose paired MC-TAOY22 IOP card.