Honeywell KCD2 Series Modules KCD2-SCD-EX1 & KCD2-STC-EX1

Technical Dossier

Product Details And Specifications

Honeywell KCD2 Series Technical Notes

The Honeywell KCD2 series is a family of DIN-rail-mounted signal conditioners and isolators engineered for hazardous-area process automation. Deployed extensively in chemical plants, oil refineries, nuclear facilities, and offshore platforms, KCD2 modules serve as the interface layer between field instruments in Zone 0/1/2 hazardous areas and safe-area control systems including DCS, PLC, and SCADA platforms. The series is manufactured to ATEX, IECEx, and FM certification standards, making it a globally accepted solution for intrinsic safety (Ex i) and non-incendive applications. Its compact 12.5 mm or 17.5 mm housing width enables high-density marshalling cabinet installations, a critical requirement in brownfield plant expansions where rack space is constrained.

KCD2 Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified KCD2 series module range, classified by function:

Smart Transmitter Power Supply / Signal Conditioners (Ex i, HART-Transparent)

• KCD2-SCD-EX1: 1-channel, 4–20 mA HART signal conditioner, Ex ia IIC, 24 VDC bus-powered, DIN rail mount, 12.5 mm width.
• KCD2-STC-EX1: 1-channel smart transmitter power supply with HART pass-through, Ex ia IIC, loop-powered field side, 24 VDC supply side.
• KCD2-SCD-EX1.SP: Variant of KCD2-SCD-EX1 with enhanced short-circuit protection for aggressive field wiring environments.
• KCD2-STC-EX1.SP: Variant of KCD2-STC-EX1 with integrated short-circuit protection and reverse polarity guard.
• KCD2-SCD-EX2: 2-channel version of the SCD-EX1, dual isolated 4–20 mA outputs, suitable for redundant DCS input cards.
• KCD2-STC-EX2: 2-channel smart transmitter conditioner, dual loop supply, HART transparent on both channels.

Switch Amplifiers / Discrete Input Modules (Ex i)

• KCD2-SR-EX1: 1-channel switch amplifier for NAMUR proximity sensors and mechanical contacts in Ex ia zones.
• KCD2-SR-EX2: 2-channel switch amplifier, dual NAMUR input, relay output, 24 VDC bus-powered.
• KCD2-SR-EX2.LB: 2-channel switch amplifier with line break and short-circuit detection on sensor lines.
• KCD2-SOT-EX1: 1-channel solenoid driver for Ex ia solenoid valves, 24 VDC, with output monitoring.

Temperature / Thermocouple / RTD Input Modules

• KCD2-UT-EX1: Universal temperature input module, supports TC (Type J/K/T/E/R/S/B) and RTD (Pt100/Pt1000), 4–20 mA output.
• KCD2-UT-EX1.2O: Dual analog output variant of KCD2-UT-EX1, for split-range or redundant temperature monitoring loops.

Frequency / Pulse Input Modules

• KCD2-FI-EX1: Frequency input module for Ex ia turbine flow meters and pulse-output sensors, 0–10 kHz input range.
• KCD2-FI-EX1.2O: Frequency input with dual 4–20 mA analog outputs for flow rate and totalizer signals.

Power Supply / Bus Modules

• KCD2-PW-EX1: 24 VDC segment power supply module for KCD2 bus rail, 500 mA output, redundancy-capable.
• KCD2-PW-EX2: High-current bus power supply, 1 A output, for high-density KCD2 marshalling racks.