2. Model Definition

51304672: Base model for 16-channel non-isolated non-HART analog input FTA

-150: Medium reinforced PCB protection grade

Medium upgraded full-board conformal coating, better resistance to humidity, dust and weak corrosive vapors than -100

Moderate high-energy bidirectional TVS transient, ESD and line fault surge protection (no channel isolation)

Dual-stage cascaded RC low-pass EMI filter for medium-noise zones with small-to-medium VFD and MCC loads

Global common ground bus for all 16 channels, no independent galvanic isolation barriers

Precision matched loop current limiting resistors to deliver uniform short-circuit overload protection

Thickened plastic channel baffles to cut down inter-channel analog signal crosstalk and leakage

3. Technical Specifications

Channel Count: 16 common-ground channels, no per-channel galvanic isolation

Compatible Field Devices

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

FTA Structure: Passive non-isolated termination board without built-in power supply; integrated dual-stage filtering, medium-energy surge protection and short-circuit current limiting

PCB Protection: Medium upgraded conformal coating; flammability UL94 V0

Terminal Type: Compression screw terminals for solid/stranded copper wire up to 14 AWG; each channel owns Ch+ / Loop–, all channels share one unified ground bus

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

Operating Ambient: 0℃ ~ +60℃ indoor cabinet; wider tolerance for humidity, dust and weak corrosion compared to -100; not applicable for salt fog or strong corrosive fume environments

Circuit Architecture Parameters

Dual-stage low-pass filtering to suppress medium-level EMI generated by VFD and motor control center equipment

Medium-energy bidirectional TVS clamps positive/negative transient high voltage on every input loop

Shared common ground design; ground potential difference between field and DCS will trigger measurement drift

Tight-tolerance current-limit resistors prevent transmitter burnout and IOP high-impedance input damage under field short faults

Thickened baffles reduce inter-channel analog bleed and cross-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: 0.357 kg

4. Interface & Communication Configuration

Inner IOP Connection: Locking flat ribbon cable directly connects to non-isolated non-HART AI IOP pin headers. Reinforced cable strain relief avoids pin deformation under sustained wiring harness tension.

Field Outer Terminals: 16 groups of Ch+ / Loop– terminals sharing a global common ground bus; field excitation circuit runs on same ground potential as DCS control side.

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

No auxiliary communication ports, only analog signal transmission supported.

5. Core Functions

Cost-effective common-ground signal transmission: Optimized for single-ground plant control room layouts to lower wiring cost.

Dual-stage medium EMI noise suppression: Reduces moderate electromagnetic interference from VFD and MCC units to stabilize measurement readings and lower fluctuation.

Medium-strength surge & short-circuit protection: Absorbs larger wiring transients and switching arcs to protect sensitive high-impedance IOP inputs and field transmitters.

Consistent loop overload safeguard: Uniform current limiting prevents transmitter damage once field wiring gets shorted accidentally.

Balanced input linearity: Matched passive components provide consistent measurement response across all 16 channels to simplify calibration work.

Redundant hot-swappable operation: Automatically adapts to primary/standby IOP switching; disconnecting and troubleshooting one channel will not disturb the other 15 measurement loops.

6. Application Scenarios

Applicable Industries

General petrochemical auxiliary areas, medium chemical plants, standard power plant auxiliary monitoring, municipal wastewater treatment, mild-humidity pharmaceutical production lines

Typical Measurement Loops

General process pressure and differential pressure transmitters

Conventional flow rate transmitters

Atmospheric storage tank level transmitters

Standard RTD/TC temperature transmitters

Water pH and conductivity analytical transmitters

Fit for single-ground plant layouts, medium-noise VFD zones, cabinets with mild elevated humidity and moderate dust accumulation, atmospheres with low-concentration weak acid/alkaline volatile vapors. Cannot be used in multi-ground sites, coastal salt fog zones and heavy corrosive chemical workshops.

7. Wiring Standards

Two-wire transmitter wiring: Transmitter positive → FTA Ch+, transmitter negative → FTA Loop– (connected to shared ground bus); reversed polarity leads to obvious measurement offset.

Cable selection: Shielded twisted-pair instrument cable for all field runs; shield grounded only at DCS cabinet FTA side, field end ungrounded to suppress ground loop noise.

Power cable separation: Keep analog instrument cables physically separated from high-voltage AC, MCC and VFD wiring to decrease EMI coupling.

8. Incompatible Hardware

All isolated AI/AO FTAs (51304644, 51304640, 51304648, 51304650), non-isolated AO FTAs, DI/DO termination boards, dedicated TC/RTD FTAs, pulse counter and serial communication terminal assemblies cannot match this non-isolated non-HART AI IOP card.