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Honeywell 51204166-175
Overview
The 51204166-175 is a 16-channel digital output relay Field Termination Assembly (FTA) built for Honeywell Experion PKS and TotalPlant Solution (TPS) architectures. The “-175” suffix denotes a conformal coating that protects the PCB against moisture, dust, and corrosive process atmospheres. The module forms the hardware bridge between digital output processors and high-power field actuators such as solenoids, motor starters, and heavy-duty indicator lamps, providing galvanic isolation between sensitive control electronics and field-side voltage transients.
Detailed content
Specifications
- Manufacturer: Honeywell
- Model: MC-TDOY23
- Part Number: 51204166-175 (conformally coated, ISA S71.04 G3 compliant)
- Module Type: Digital Output Relay FTA
- Channels: 16 isolated relay output channels
- Contact Type: Electromechanical dry contacts
- Switching Voltage: Up to 240 VAC / 125 VDC
- Control (System) Voltage: 24 VDC
- Operating Temperature: 0 °C to +60 °C (32 °F to 140 °F)
- Storage Temperature: -40 °C to +85 °C
- Humidity: 5% to 95% RH, non-condensing
- Isolation: Complete optical and mechanical (galvanic) isolation between I/O processor and field circuits
- Mounting: DIN-rail or panel mount within TDC 3000 marshalling cabinets
- Dimensions: 31.0 cm × 15.0 cm × 8.0 cm
- Weight: 1.00 kg
- Certifications: CE, UL, RoHS compliant
Features
- 16 independent relay dry-contact outputs for discrete field control
- Conformal coating defends against H₂S, chlorine, and high-humidity corrosion
- Per-channel LED status indicators for diagnostics
- Drop-in functional equivalent to the non-coated 51204166-075
- Seamless integration with Honeywell Digital Output IOP cards (no database changes required)
- Redundant configuration support for critical interlocks
Applications
Petrochemical and oil-refinery process control, power-plant turbine and boiler auxiliaries, water/wastewater treatment discrete valve sequencing, and hazardous-area marshalling cabinets.
Installation & Notes
Mount in a standard TDC 3000 marshalling panel using DIN rail or panel screws. Connect the multi-pin cable interface to the Digital Output IOP card; wire field devices to screw-compression terminals accepting 20–12 AWG (0.5–2.5 mm²). Bond the chassis ground stud to the cabinet earth bar. Do not energize field circuits until the conformal coating and all terminations are visually inspected. The -175 coated version must be used in environments with corrosive gas or high humidity to prevent pin micro-corrosion.
