MC-TAIH02 Honeywell High-Level Analog Input / STI FTA Module

Description

Product Model: MC-TAIH02 (51304453-150)
Product Brand: Honeywell
Product Series: Experion / FTA (High Level Analog Input / STI)

Key Features:

• Supports High-Level Analog Input plus STI (Smart Transmitter Interface) for field device communications.
• Input range capability: –40 mA to +20 mA as per vendor spec.
• Operates on 24 V DC supply and supports a wide ambient temperature range (–40 to +70 °C).
• Mountable in Experion / UCN input racks, used as a field termination assembly to interface field analog / STI devices to the control logic.

Product Role & System Fit

In Honeywell’s DCS / I/O architecture (Experion, UCN, FTA series), field wiring often terminates in Field Termination Assemblies (FTA) that condition, isolate, and route signals into the logic domain. The MC-TAIH02 is one such FTA card, used where the field devices provide high-level analog signals or STI (Smart Transmitter Interface) communication. Its role is to act as the bridge between field sensors/transmitters and the control hardware, ensuring accurate analog input pickup plus support for serial communication capability.

Because STI (Smart Transmitter Interface) allows digital communications over the same pair of leads as analog signals (for diagnostics, calibration, etc.), the MC-TAIH02 is especially useful in processes where you want both analog measurement and remote device interaction in one module.

You would typically install MC-TAIH02 in an FTA slot—mounted in the field (or field-adjacent) enclosures, connecting to field wires (4–20 mA loops or STI signals), and providing isolated outputs or forwarding to higher I/O modules or controllers. In many installations, it coexists with other FTA cards (digital inputs, analog outputs, low-level inputs) to create a full field interface rack.

Because of its capability, it’s favored in greenfield or upgrade paths where future instrumentation might leverage STI diagnostics without changing wiring.

Technical Features & Benefits

Input Range, Mode & STI Support

• The vendor spec lists analog input range of –40 mA to +20 mA. That suggests the module can accept some overrange or bidirectional current signals (perhaps for sensor loops or measurement flexibility).
• The module supports STI (Smart Transmitter Interface) communication at up to 19.2 kbps. This enables two-way digital communication with transmitters for configuration, health diagnostics, etc.
• Input circuitry likely includes filtering, isolation, and signal conditioning to deliver stable analog values to the logic domain, while maintaining STI signaling on top of the analog path.

These features enable flexible integration with modern smart instrumentation, reducing need for separate wiring or interface cards.

Electrical & Environmental

• Operating voltage: 24 V DC supply (standard in Honeywell I/O ecosystems) is required.
• Ambient temperature: –40 to +70 °C, which covers many industrial / outdoor environments.
• Other reported specs by a reseller: input voltage range 0–10 VDC, current consumption ~10 mA, ±0.2 % reading accuracy, insulation resistance ~10 MΩ, dielectric strength 2 kV, weight ~0.5 kg, dimensions ~120×70×40 mm.

While these additional numbers from the reseller are plausible, I would treat them as indicative until validated against the hardware label or official datasheet.

Mounting, Termination & Isolation

• As an FTA card, the MC-TAIH02 is designed to fit into termination racks or field enclosures. It likely connects via standard backplane or FTA connectors, integrated in the larger UCN / I/O architecture.
• Because of the inherent analog + digital signaling, isolation between field side and logic side is important. The FTA designs in Honeywell systems typically include galvanic isolation and protective circuitry to prevent field faults from propagating into the controller domain.
• The module likely supports redundancy paths (depending on FTA design), although I did not find a confirmed redundancy spec for MC-TAIH02 in the sources I saw.

In sum, its design blends analog input capacity, smart transmitter interface, and field interfacing robustness.

Technical Specifications Table

Here’s a compiled table of known and inferred specs for MC-TAIH02. Use this as a starting guide; verify against your actual unit or datasheet.

Note: Some of the specs (reseller ones) are not confirmed by OEM datasheets; use them cautiously.

Installation & Maintenance Insights

Here are some practical recommendations based on field experience with similar Honeywell FTA modules.

Mounting & Rack Insertion

• During installation, ensure the MC-TAIH02 is firmly seated in its FTA slot, with no gap or poor contact—looseness may lead to signal errors, especially given the mixed analog + digital signaling.
• If part of a redundancy / hot-swap architecture, confirm that the redundant path or backup FTA is synchronized and configured properly.
• Maintain proper ventilation and thermal management—electronics under direct sunlight or close packing may overheat and drift.

Wiring Best Practices

• Use shielded, twisted-pair wiring for analog loops and STI communications to reduce EMI and avoid signal distortion.
• Maintain good grounding and shielding practices: connect the shield at one end only (typically the FTA end) to prevent ground loops.
• Keep analog wiring away from power or high-current lines.
• Check for polarity and wire correctness before energizing—miswiring can damage input stages or lead to erroneous readings.

Commissioning & Calibration

• During commissioning, apply known analog currents (e.g. 4 mA, 12 mA, 20 mA) and verify readings in the host DCS / logic system.
• If STI is used, verify communication paths with the field transmitters (diagnostic readouts, calibration, device attributes).
• Monitor stability over time and temperature, and check for drift or noise anomalies.

Replacement & Spares Strategy

• Keep a spare MC-TAIH02 (same part number / revision) in inventory, as FTA modules are often subject to field damage, wiring faults, or replacement cycles.
• Before installing a spare, test its input channels offline with known signals to confirm correct behavior.
• Maintain consistent labeling and mapping of channels, so swapping does not introduce wiring confusion.