2. Model Definition

51304736: Base model for 16-channel non-isolated non-HART analog input FTA

-325: Ultra heavy-duty reinforced PCB protection grade

Thick multi-layer military-grade full-board conformal coating, exceptional resistance to extreme humidity, conductive heavy dust, moderate-severe corrosive chemical vapors and intermittent light salt mist

Multi-stage composite high-energy bidirectional surge absorption stack (TVS + fast transient absorber), far higher transient withstand energy than -200 and lower grades, no channel isolation

Three-stage fully symmetrical cascaded RC differential EMI filter, precision calibrated for ultra-high-noise heavy industrial zones with massive VFD clusters, full MCC banks and medium-voltage switchgear

Global unified common ground bus for all 16 channels; no independent galvanic isolation barriers between individual input loops

Oversized reinforced loop short-circuit current limiting resistor arrays to fully protect heavy-duty transmitters and delicate IOP high-impedance input circuits

Ultra-precision ultra-tight tolerance matched input impedance resistors for perfectly uniform full-range 4–20mA measurement accuracy across all 16 channels

Extra-wide ultra-thick flame-retardant reinforced plastic channel partition baffles to fully eliminate inter-channel analog leakage and cross-loop signal crosstalk

3. Technical Specifications

Channel Count: 16 fully shared-ground input loops, no per-channel galvanic isolation

Compatible Field Devices

Two-wire heavy-duty non-HART 4–20mA transmitters: pressure, differential pressure, flow, level, temperature, pH, dissolved oxygen, conductivity heavy industrial transmitters

FTA Structure: Passive non-isolated termination board with no internal power supply; integrated three-stage symmetrical differential filtering, multi-tier ultra-high-energy surge protection and extreme heavy short-circuit overload limiting, no HART coupling circuit

PCB Protection: Thick multi-layer military reinforced conformal coating; flammability UL94 V0

Terminal Type: Compression screw terminals for solid/stranded copper wire up to 14 AWG; each channel has Ch+ / Loop– field terminals tied to unified global ground bus

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

Operating Ambient: 0℃ ~ +60℃ indoor control cabinet; humidity, dust and moderate-severe corrosion tolerance greatly exceeds -200 and lower grades; tolerates intermittent light salt mist; continuous heavy coastal salt fog requires upgrade to -375 grade

Circuit Architecture Parameters

Three-stage symmetrical low-pass differential filtering suppresses extreme industrial EMI without distorting 4–20mA analog measurement amplitude

Multi-tier composite bidirectional surge stack clamps extreme positive/negative transient high voltage on every shared-ground input loop

Shared common ground design: ground potential discrepancies between field and DCS will still trigger slight measurement drift; isolated FTA required for complex multi-ground plant systems

Ultra-tight precision input impedance guarantees stable full-span 4–20mA conversion precision with minimal deviation

Oversized high-power current-limit resistors prevent transmitter burnout and IOP input permanent damage under sustained field short faults

Ultra-thick flame-retardant baffles fully block inter-channel analog bleed and cross-loop measurement interference

Redundancy Support: Fully compatible with primary/standby redundant non-isolated non-HART AI IOP; hot-swap FTA replacement allowed without process shutdown

Approximate Unit Weight: 0.363 kg

4. Interface & Communication Configuration

Inner IOP Connection: Locking heavy-duty flat ribbon cable directly mates to non-isolated non-HART AI IOP pin headers. Reinforced multi-point heavy-duty cable strain relief prevents pin header deformation or fracture under long-term sustained tension of lengthy multi-core field wiring harnesses.

Field Outer Terminals: Independent Ch+ / Loop– terminals for each two-wire transmitter loop; all input loops reference one unified ground bus aligned with DCS control ground potential.

Signal Mechanism: Pure 4–20mA DC analog measurement signals; no HART circuit integrated.

No auxiliary communication ports; only analog measurement signal transmission supported.

5. Core Functions

Common-ground cost-effective heavy-load signal acquisition: Optimized for single-ground large industrial plants collecting signals from heavy-duty non-HART field transmitters.

Three-stage symmetrical ultra-heavy EMI rejection: Suppresses extreme intense electromagnetic interference from large VFD systems, MCC banks and medium-voltage switchgear to eliminate severe measurement fluctuation and unstable readings.

Multi-tier ultra-high-energy surge & short-circuit overload protection: Withstands lightning-induced line transients, high-magnitude equipment startup surges and sustained field short-circuit high voltage to protect expensive sensitive IOP high-impedance input circuits and critical heavy-duty field transmitters.

Extreme heavy-duty uniform loop overload protection: Oversized current-limiting resistor arrays evenly safeguard all channels from short-circuit burnout for uninterrupted long-term critical process monitoring.

Consistent channel measurement precision: Ultra-precision matched passive components deliver identical conversion accuracy across all 16 channels to reduce bulk calibration workload.

Redundant hot-swappable operation: Seamlessly synchronizes with primary/standby IOP switching logic; single-channel disconnection and troubleshooting do not impact operation of remaining 15 critical measurement loops.

6. Application Scenarios

Applicable Industries

Large integrated petrochemical complexes, heavy chemical synthesis plants, combined heat & power generation stations, massive oil & gas refineries, pulp & paper mills, high-humidity industrial wastewater treatment, heavy-batch pharmaceutical manufacturing lines, inland coastal sites with intermittent light salt mist, large single-ground process plants

Typical Measurement Loops

Critical safety system pressure/differential pressure heavy-duty non-HART transmitters

High-volume process flow heavy industrial conventional transmitters

Oversized vertical storage tank level measurement transmitters

Furnace/reactor high-temperature transmitters

Process severe-corrosion medium pH/DO/conductivity analytical transmitters

Ideal for single-ground large plant layouts, ultra-dense VFD heavy-noise process areas, cabinets with persistent extreme high humidity and heavy conductive dust accumulation, atmospheres containing moderate-to-severe acidic/alkaline volatile vapors, inland sites with occasional light salt mist. Not suitable for offshore platforms or coastal locations with continuous heavy salt fog exposure (upgrade to -375 for full salt fog resistance).

7. Wiring Standards

Two-wire transmitter wiring: Transmitter positive → FTA Ch+, transmitter negative → FTA Loop– (shared ground bus); reversed polarity generates measurable measurement offset and degrades surge protection performance.

Cable specification: Heavy-duty shielded twisted-pair instrument cable for all field wiring runs; cable shield grounded solely at DCS cabinet FTA side with field transmitter end ungrounded to fully suppress residual ground loop noise.

Power cable segregation: Physically separate analog measurement cables from high-voltage AC power, MCC and VFD output wiring to minimize capacitive and inductive EMI coupling interference.

8. Incompatible Hardware

All isolated AI/AO FTAs (51304644, 51304640, 51304728, 51304730), non-isolated HART AI (51304685), non-isolated AO FTAs (51304690, 51304718), discrete DI/DO termination boards, TC/RTD dedicated FTAs, pulse counter termination blocks and serial communication terminal assemblies cannot be paired with this non-isolated non-HART AI IOP card.