Honeywell FTA‑T‑21

Technical Specifications: Signal support: Fail‑safe digital input and digital output mixed channels Terminal type: Screw‑locking field‑wiring terminal block Maximum applicable wire cross‑section: AWG14 Rated working voltage: 24 V DC safety‑loop voltage Per‑channel maximum continuous current: 2 A Rear‑side interface: Dedicated multi‑pin connector for safety‑system interconnection‑cable Operating temperature: ‑20 °C ~ +65 °C Protection class: IP20 Certifications: CE, UL, CSA, TUV safety‑relevant certification Mounting method: Cabinet rack‑mount installation

Functional Features: Mixed‑channel safety‑digital‑input and digital‑output field‑wiring termination Screw‑locking terminals ensure stable connection for field‑site cables Dedicated interconnection‑cable interface docks with safety‑main mixed‑I/O module Internal circuit supports field‑loop fault diagnosis signal return for main‑module Channel‑independent wiring‑loop design reduces cross‑channel interference Meet SIL‑level safety‑instrument‑system field‑wiring termination requirement

Application Scenarios: Safety‑instrument‑system mixed‑digital‑I/O field‑wiring termination Emergency‑shutdown system field‑limit‑switch digital‑input and solenoid‑valve digital‑output comprehensive termination Petrochemical plant SIS system safety‑field‑device signal distribution cabinet Chemical‑industry safety‑interlock system field‑signal‑wiring interface Oil‑gas‑plant safety‑control cabinet mixed‑signal termination

Material Composition: Housing: Flame‑retardant engineering‑plastic housing Terminal block: Reinforced‑nylon base with tin‑plated copper screw terminals Internal circuit‑board: FR‑4 flame‑retardant printed‑circuit‑board Rear‑side connector: Gold‑plated multi‑pin industrial connector

Structural Characteristics: Rack‑mount modular structure for cabinet‑internal installation Front‑panel partition‑arranged screw‑terminals for field‑input‑output cable access Rear‑side multi‑pin connector for safety‑system interconnection‑cable connection Physically separated area for input‑channel terminals and output‑channel terminals No moving mechanical components inside assembly

Working Principle: Field‑site safety‑digital‑input signal from limit‑switch or safety‑sensor connects to FTA‑T‑21 input‑terminals. Safety‑digital‑output signal from safety‑main‑module transmits through interconnection‑cable to FTA‑T‑21 internal circuit and routes to output‑terminals for driving field‑solenoid‑valve or actuator. Internal circuit maintains signal‑loop integrity, enables safety‑main‑module to detect field‑loop open‑circuit and short‑circuit fault. Input‑loop and output‑loop keep electrical isolation to avoid signal mutual interference.

Installation Requirements: Mount inside IP20 industrial‑control cabinet. Connect rear‑side multi‑pin connector with matched interconnection‑cable to safety‑system mixed‑I/O main‑module. Field‑site device cables connect to corresponding front‑panel screw‑terminals, tighten terminal‑screws to specified torque. Safety‑signal wiring shall separate from non‑safety power‑cable routing. Complete cabinet protective‑ground connection. Ambient operating temperature must keep within ‑20 °C ~ +65 °C range.

Usage Notes: Do not exceed single‑channel maximum 2 A continuous‑current rating. Confirm interconnection‑cable model matches FTA‑T‑21 and mixed‑I/O main‑module. Forbid hot‑unplug interconnection‑cable under safety‑system running‑state. Regularly check terminal‑screw tightening‑condition. Prevent conductive‑dust and moisture from accumulating inside cabinet. Do not deploy in severe corrosive‑gas environment without cabinet‑protective‑measures.