2. Model Definition

51204168: Base part number for HLAI & STI shared analog input FTA

-100: Standard original PCB hardware revision

Matched IOP Cards:

MU-PAIH01 (51303991-200) HLAI high-level analog input module

STI smart transmitter interface IOP cards

Not compatible with DI, DO, AO, LLAI series FTA boards.

3. Technical Specifications

Supported Signal Types: 4–20 mA 2-wire transmitters, HART-enabled smart transmitters, standard high-level analog current signals

Channel Capacity: Matches channel count of paired HLAI/STI IOP

Loop Supply: 24 VDC loop power fed from cabinet system power for field transmitters

PCB Flame Rating: UL94 V0 fire-retardant substrate

Mounting: Snap-on installation for standard 35 mm DIN rail

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

Circuit Design: Passive structure with built-in RC EMI filter and per-channel current-limiting protection

Terminal Type: Red screw-clamp terminals for secure instrument cable wiring

Approximate Weight: ~0.32 kg

4. Interface & Communication Configuration

Inner Connection to IOP: Dedicated flat ribbon cable connector directly plugged into HLAI/STI IOP card. No independent communication circuit; signal transmission relies entirely on UCN control bus via the matched IOP module.

Outer Field Terminals: Clearly marked positive/negative terminals for each transmitter loop, partitioned layout for neat wiring.

Power Source: 24 VDC system power from control cabinet supplies transmitter excitation loops.

5. Core Functions

Strain relief for thick instrument cables to prevent bent/damaged pins on expensive HLAI/STI IOP cards.

EMI suppression filter reduces interference from motors, inverters and high-power contactors to stabilize analog measurement values.

Per-channel current limiting prevents burnout of IOP hardware if field transmitter wiring is short-circuited.

Unified terminal layout simplifies loop calibration, troubleshooting, disconnection and commissioning work.

Supports both single non-redundant and redundant dual IOP cabinet configurations.

Compatible with HART protocol smart transmitters for digital parameter access alongside 4–20mA analog reading.

6. Application Scenarios

Process industries including petrochemical, chemical plant, thermal power, oil & gas, pulp & paper, metallurgy using Honeywell Experion PKS UCN HPM control systems.

Measurement loops for pressure, flow, liquid level, temperature via 4–20mA/HART two-wire transmitters.

Standard supporting terminal assembly for HLAI/STI analog input slots in DCS I/O cabinets.

7. Operation & Maintenance Instructions

Matching Restriction: Only pair with MU-PAIH01 HLAI or STI IOP cards; must not substitute DI, DO, AO, low-level analog FTA units.

Wiring Rules: Strictly follow polarity labels for transmitter positive/negative leads; use shielded instrument cable with single-point shield grounding at cabinet side.

Spare Part Swap: 51204168-100 and 51204168-150 share identical electrical performance for emergency replacement; use same suffix model for long-term stable operation.

Fault Troubleshooting Sequence: No measurement reading → Tighten terminal screws → Test loop current of transmitter → Inspect ribbon cable insertion status → Diagnose paired HLAI/STI IOP card.