Technical Specifications

• Part Number: 51304638‑125 (51304638125)

• Alternative ID: MC‑GAOX12, Analog Output FTA, 8‑Ch 4‑20 mA Isolator

• Module Type: Field Terminal Assembly (FTA), Analog Output Isolation

• System Compatibility: Honeywell UCN, TDC3000, TPS (LCN & UCN networks)

• Output Channels: 8 isolated channels (4‑20 mA DC, sink/source configurable)

• Isolation Rating: 1500 VAC (channel‑to‑backplane), 2500 VAC surge immunity

• Resolution: 12‑bit (0.025% of full scale)

• Accuracy: ±0.05% FS @ 25°C; ±0.1% FS over temperature range

• Update Rate: 10 ms per channel

• Load Resistance: 0–600 Ω (per channel)

• Power: 24 VDC ±10%, 150 mA (external or backplane‑fed)

• Power Consumption: ~3.6 W

• Operating Temperature: 0°C to +60°C (industrial standard)

• Storage Temperature: ‑40°C to +85°C

• Humidity: 5%–95% RH, non‑condensing

• Dimensions (H×W×D): 152 × 127 × 25 mm (6‑inch FTA)

• Weight: ~0.30 kg

• Coating: Conformal coated (harsh environment grade)

• Certifications: CE, RoHS, UL 508 compliant

• Revisions: Common Rev S (hardware/firmware)

• Status: Active (new surplus/repair available; backward compatible with 51304638‑100/175/600)

Interface & Communication Configuration

• Host Interface: UCN/TDC3000 backplane (proprietary, 1 Mbps)

• Field Interface: 8 × screw terminals (4‑20 mA, isolated per channel)

• Protocol Support: UCN analog output protocol; compatible with all Honeywell UCN analog controllers

• Diagnostics: 2 on‑board LEDs (Power, Fault); remote alarm via UCN; channel‑specific fault logging (open/short circuit)

• Hot Swap: Yes (replace without system shutdown; auto‑reconnect in <5 seconds)

• Compatibility: Drop‑in replacement for 51304638‑100/175/600; works with MC‑TAIH15, MC‑TDID72, and other UCN FTAs

Core Functions

1. Analog Output Isolation: 8‑channel galvanic isolation breaks ground loops, blocking common‑mode voltage and noise between DCS and field devices.

2. Signal Conditioning: Converts UCN controller digital signals to precision 4‑20 mA analog outputs for valves, actuators, and VFDs.

3. Fault Protection: Isolates channel faults (open/short) from the backplane; surge protection prevents damage from lightning or switching transients.

4. High‑Accuracy Control: 12‑bit resolution and ±0.05% FS accuracy ensure precise process control in critical loops.

5. Harsh Environment Reliability: Conformal coating and wide temperature range suit chemical, petrochemical, and power generation facilities.

Application Scenarios

• Process Control Loops: Regulating flow, pressure, temperature, and level via 4‑20 mA control valves and actuators.

• Motor Control: Driving variable‑frequency drives (VFDs) for pump/fan speed control in noisy industrial environments.

• Legacy System Integration: Isolating modern UCN controllers from older, ungrounded field devices in TDC3000/TPS upgrades.

• High‑Noise Areas: Chemical plants, refineries, and power substations with heavy electrical interference.

Compatibility Note

• System Compatibility: Honeywell UCN, TDC3000, TPS (requires UCN analog controller card)

• Replacement Cross‑Reference:

  • 51304638‑100: Standard isolation, 0–55°C

  • 51304638‑125: Enhanced isolation, 0–60°C, Rev S firmware

  • 51304638‑175: High‑temperature variant, ‑20°C to +70°C

  • 51304638‑600: 8‑channel, high‑surge (3000 VAC) version

• Key Difference (100 vs 125): The 125 revision adds extended temperature (0–60°C), improved surge immunity (2500 VAC), and Rev S firmware with enhanced fault diagnostics.