2. Model Definition

51304584: Base model for 16-channel non-isolated HART analog input FTA

-200: Medium heavy reinforced industrial PCB grade

Medium-thick reinforced full-board conformal coating, excellent anti-humidity, dust and mild corrosive vapor performance vs -100/-150

High-capacity bidirectional TVS transient, ESD and wiring fault surge suppression per channel

Three-stage cascaded RC EMI filter network optimized to protect low-amplitude HART AC modulation without signal attenuation

High-precision low-ESR HART coupling capacitor arrays for stable bidirectional digital polling

Tight-tolerance isolated-style loop current limiting resistors for uniform short-circuit overload protection

Extra-thick reinforced physical channel isolation barriers to eliminate inter-channel analog/HART signal crosstalk

Matched IOP Hardware: Honeywell 16-channel non-isolated HART 4–20mA analog input UCN IOP card

Incompatible Hardware: Isolated HART AI (51304518), non-HART AI/AO FTAs, isolated DI/DO, TC/RTD LLAI, pulse counter, serial communication FTAs

3. Technical Specifications

Channel Count: 16 independent non-isolated HART 4–20mA analog input channels

Supported Field Devices

Two-wire HART 4–20mA smart transmitters (pressure, flow, level, temperature, pH, conductivity, dissolved oxygen)

Backward compatible with conventional non-HART 4–20mA two-wire transmitters

FTA Structure: Fully passive termination block; no onboard isolated power; per-channel HART coupling, filtering, surge and overload protection integrated

PCB Protection: Medium-thick reinforced conformal coating; flammability UL94 V0

Terminal Type: Compression screw terminals, solid/stranded copper wire up to 14 AWG

Form Factor: Standard Size B footprint, snap-on DIN rail mount for 35 mm standard rails

Operating Ambient: 0℃ ~ +60℃ indoor cabinet only; wider tolerance for high humidity, dust and mild corrosion compared to -100/-150 grades

Circuit Architecture

Three-stage low-pass EMI filtering to suppress heavy switching noise from large VFD banks, MCCs and medium-voltage switchgear

High-energy bidirectional transient overvoltage surge suppression on Ch+ and loop return lines

Low-distortion HART coupling networks to maintain full HART signal swing across long instrument cables

Calibrated current-limit resistors to prevent transmitter and IOP input burnout during field short faults

Extra-thick isolation partitions to block cross-channel analog bleed and HART interference

Redundancy Compatibility: Fully supports primary/standby redundant non-isolated HART AI IOP architecture; hot-swap IOP card replacement permitted

Approximate Unit Weight: 0.360 kg

4. Interface & Communication Configuration

Inner IOP Connection: Locking heavy-duty flat ribbon cable connector directly mates to non-isolated HART AI IOP pin headers. Reinforced cable strain relief prevents pin header deformation or fracture under long-term tension of multi-core instrument wiring harnesses. Combined DC 4–20mA + superimposed HART AC signals pass through three-stage filters and heavy surge protection networks directly to the IOP. The IOP performs A/D conversion, HART modulation/demodulation, sensor fault diagnostics, and transmits process values, device alarms and calibration status over UCN bus to Experion PKS controller.

Field Outer Terminals: Clearly labeled Ch+ / Loop– terminals for two-wire transmitter wiring; loop excitation power is fully supplied by the paired non-isolated HART AI IOP through FTA passive circuits.

Loop Power Source: Regulated 4–20mA loop excitation current sourced exclusively from the HART analog input IOP card.

5. Core Functions

Cable Strain Relief: Heavy-duty reinforced strain relief protects fragile HART AI IOP pin headers from mechanical stress, bending and fatigue fracture caused by continuous pulling force on multi-core field instrument cables.

Three-Stage Ultra-Stable HART EMI Rejection: Three-layer cascaded filter architecture drastically outperforms single-stage (-100) and dual-stage (-150) variants; eliminates PV drift, frequent HART poll retries, timeouts and "no device detected" faults in high-noise motor/VFD and power switchgear zones, while preserving full HART communication bandwidth.

Reinforced Surge & Short-Circuit Fault Protection: High-capacity TVS clamping diodes absorb intense induced voltage spikes, wiring short-circuit transients and switching arc surges, delivering robust protection for sensitive high-impedance HART IOP input circuits.

Medium Heavy-Duty Anti-Corrosion Environmental Barrier: Medium-thick reinforced conformal coating fully encapsulates PCB substrate, solder pads, copper traces and all passive components. Ensures stable 24/7 continuous process measurement and HART diagnostic polling under long-term high humidity, heavy dust accumulation and trace mild acidic/alkaline corrosive fumes.

Uniform Loop & HART Channel Consistency: Precision matched coupling capacitors and current-limit resistors guarantee identical loop excitation voltage, analog linearity and HART signal gain across all 16 input channels, eliminating channel-to-channel calibration mismatch.

Independent Single-Channel Isolated Maintenance: Separate terminal blocks support HART transmitter replacement, full loop resistance/insulation testing, handheld HART communicator connection and fault troubleshooting for one measurement loop without disrupting the other 15 critical process inputs.

Redundancy Hot-Swap Capability: Standby redundant non-isolated HART AI IOP cards can be replaced online without losing critical process PV values, HART device fault alarms, batch thermal/flow profile data or calibration records.

6. Application Scenarios

Applicable Industries

Petrochemical complexes, medium-heavy chemical processing plants, thermal & combined-cycle power stations, oil & gas refineries, pulp & paper mills, high-humidity wastewater treatment facilities, medium-to-high humidity pharmaceutical batch production lines.

Non-Isolated HART Analog Measurement Loops

HART differential pressure / gauge pressure transmitters, mass / vortex / turbine flow transmitters, radar / ultrasonic level transmitters, smart RTD/TC temperature transmitters, pH/ORP/DO/conductivity analytical HART transmitters; designed for plant sites with unified single-ground DCS cabinet layouts (ground loop risk low).

Cabinet Deployment

Dedicated compact slot for 16-point non-isolated HART analog input inside high-density space-saving critical DCS I/O control cabinets.

7. Wiring, Operation & Maintenance Guidelines

Wiring Standards

Two-wire transmitter wiring: Transmitter positive → FTA Ch+, transmitter negative → FTA Loop–; reversed polarity creates significant measurement offset and degraded HART signal amplitude/stability.

Handheld HART communicator connection: Clip test leads across Ch+ / Loop– terminals at FTA or transmitter; no external load resistor required for standard two-wire HART loops.

Deploy shielded twisted-pair low-capacitance instrument cable for all field runs; implement single-point shield grounding only at the DCS cabinet FTA side to suppress ground loop noise and HART communication instability.

Route HART analog signal cables physically separated from high-current AC power, MCC and VFD output wiring to minimize EMI coupling interference; maintain maximum practical separation from large motor power feeders.

Spare Part Interchangeability

51304584-200 shares identical non-isolated HART analog input circuit topology with -100/-150 variants, fully electrically interchangeable for emergency field substitution. The -200 medium heavy reinforced grade is specified for cabinet environments with obvious high humidity, heavy dust or trace corrosive gas where -100/-150 lack long-term stability and surge withstand margin.

Standard Fault Troubleshooting Flow

PV drift / intermittent HART timeouts / no transmitter recognition / saturated high/low reading → Retighten compression terminal screws → Measure loop current at transmitter terminals → Test loop for opens, shorts and insulation resistance → Verify transmitter operating power draw → Confirm ribbon cable fully locked into non-isolated HART AI IOP header → Diagnose operational health of paired HART IOP card.