2. Model Definition

51304650: Base model for 16-channel galvanically isolated non-HART analog input FTA

-250: Heavy-duty reinforced PCB protection grade

Multi-layer thick reinforced full-board conformal coating with superior resistance to high humidity, heavy dust and moderate corrosive chemical vapors

Upgraded high-energy composite bidirectional TVS surge stack, higher transient withstand energy than -200 and lower suffixes

Three-stage symmetrical cascaded RC differential EMI filter, tuned for extreme high-noise zones with massive VFD clusters and large motor control centers

Per-channel reinforced galvanic isolation barriers with extended creepage & clearance distances to completely eliminate field-DCS ground loop circulating currents

Extra-precision tight-tolerance isolated series current limiting resistors for perfectly uniform short-circuit overload protection across all 16 channels

Extra-wide thickened physical channel isolation partitions to eliminate inter-channel analog leakage and measurement crosstalk

3. Technical Specifications

Channel Count: 16 fully independent channels, each with complete galvanic isolation

Compatible Field Devices

Two-wire non-HART 4–20mA transmitters: pressure, differential pressure, mass/vortex/turbine flow, radar/float level, RTD/TC temperature, pH, ORP, dissolved oxygen, conductivity analytical transmitters

FTA Structure: Passive isolated termination board with no internal power supply; integrated per-channel three-stage symmetrical filtering, high-energy surge protection and precision short-circuit current limiting

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

Terminal Type: Compression screw terminals, fit solid/stranded copper wire up to 14 AWG; each channel has independent isolated Ch+ / Loop– terminal pair

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

Operating Ambient: 0℃ ~ +60℃ indoor control cabinet; humidity, dust and moderate corrosion tolerance surpasses -200 and lower grades; not certified for continuous salt fog (select -325/-375 for coastal/offshore salt fog environments)

Circuit Architecture Parameters

Three-stage symmetrical low-pass differential filtering, precisely calibrated to suppress severe industrial EMI without signal distortion

Composite high-energy bidirectional TVS stack suppresses positive/negative transient high voltage on every isolated input loop

Reinforced galvanic isolation barrier eliminates measurement drift triggered by ground potential differences between separate grounding grids

Low-ESR stable passive components maintain clean 4–20mA DC measurement signal without attenuation

Precision current-limit resistors fully protect transmitters and IOP high-impedance inputs from short-circuit burnout

Extra-thick isolation partitions fully block inter-channel analog bleed and cross-measurement interference

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

Approximate Unit Weight: 0.361 kg

4. Interface & Communication Configuration

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

Field Outer Terminals: Independent isolated Ch+ / Loop– terminals for each two-wire transmitter loop; field excitation circuit is fully galvanically separated from DCS control ground potential.

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

No auxiliary communication ports; only analog process signal transmission is supported.

5. Core Functions

Full per-channel galvanic isolation: Eliminates circulating ground loop currents at multi-ground plant sites, fixing unstable PV readings and persistent measurement drift.

Three-stage symmetrical heavy EMI noise rejection: Suppresses intense electromagnetic interference from large VFD systems, MCCs and medium-voltage switchgear to eliminate measurement jitter and fluctuation.

High-energy surge & short-circuit fault protection: Withstands lightning-induced line transients, equipment startup surges and field short-circuit high voltage to protect sensitive costly IOP high-impedance input semiconductors.

Heavy-duty loop overload safeguarding: Uniform precision current limiting prevents transmitter damage under accidental field wiring short conditions.

Consistent input linear performance: Ultra-precision matched passive components deliver identical measurement response across all 16 channels to reduce bulk calibration workload.

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

6. Application Scenarios

Applicable Industries

Petrochemical complexes, heavy chemical synthesis plants, combined heat & power generation stations, large oil & gas refineries, pulp & paper mills, high-humidity industrial wastewater treatment, medium-to-high humidity pharmaceutical batch manufacturing lines

Typical Measurement Loops

Emergency safety shutoff system pressure/DP transmitters

High-volume heavy-duty process flow transmitters

Large vertical storage tank level transmitters

Furnace/reactor high-temperature RTD/TC transmitters

Moderately corrosive media pH/DO/conductivity analytical transmitters

Ideal for multi-ground plant layouts, VFD-dense process areas, cabinets with persistent high humidity and heavy dust accumulation, and atmospheres containing moderate acidic/alkaline volatile vapors. Not suitable for offshore platforms or coastal sites with continuous salt fog exposure; upgrade to -325/-375 ultra-heavy-duty grades for those extreme environments.

7. Wiring Standards

Two-wire transmitter wiring: Transmitter positive → isolated FTA Ch+, transmitter negative → isolated Loop–; reversed polarity generates minor measurable PV offset.

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

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

8. Incompatible Hardware

Isolated HART AI (51304644), isolated non-HART AO (51304640), isolated HART AO (51304648), all non-isolated AI/AO FTA modules, discrete DI/DO termination boards, TC/RTD dedicated FTAs, pulse counter termination blocks and serial communication terminal assemblies cannot be paired with this isolated non-HART AI IOP card.