Product Overview

The Pepperl+Fuchs KFD2-SR2-Ex2.W functions as a high-reliability 2-channel isolated barrier, facilitating the safe transfer of digital signals from hazardous areas to the control room. This module interfaces seamlessly with NAMUR proximity sensors or dry contact switches located in Zone 0, 1, or 2, effectively converting field inputs into clean relay contact outputs for PLC or DCS integration. By providing robust galvanic isolation, the KFD2-SR2-Ex2.W prevents dangerous energy levels from entering explosive atmospheres, ensuring the highest level of intrinsic safety for petrochemical plants, refineries, and pharmaceutical manufacturing. Each channel operates independently, allowing engineers to monitor two distinct field points—such as valve positions or tank levels—using a single, space-saving 20mm module.

Core Technical Advantages

This switch amplifier incorporates advanced Line Fault Detection (LFD) capabilities, which continuously monitor the field circuit for lead breakage or short-circuit conditions. When a fault occurs, the module triggers a dedicated red LED and de-energizes the output relay, providing instantaneous diagnostic feedback to the maintenance team. The hardware features a reversible output mode, enabling users to select between "Normally Open" and "Normally Closed" logic via easily accessible DIP switches located on the front panel. Additionally, the KFD2-SR2-Ex2.W supports Power Rail integration, which eliminates complex point-to-point power wiring by drawing 24V DC directly from the DIN rail bus. This hardware architecture significantly reduces cabinet clutter while increasing the overall MTBF (Mean Time Between Failure) of the safety loop.

Technical Specifications

Installation Guide

Engineers must mount the KFD2-SR2-Ex2.W on a standard 35 mm DIN rail, ensuring a minimum clearance of 5mm between adjacent modules to facilitate natural convection cooling. When utilizing mechanical contacts in the field, always install a 10 kΩ shunt resistor and a 1 kΩ series resistor to allow the Line Fault Detection (LFD) circuitry to distinguish between a closed contact and a short circuit. All hazardous area wiring must follow intrinsic safety standards, maintaining a minimum distance of 50mm from safe-area power or signal cables. Verify that the DIP switch settings for Phase Reversal and LFD match the specific logic requirements of the control system before commissioning. To ensure maximum reliability, terminate all cable shields at the safe-area ground bar rather than at the barrier terminals.

Engineering Advantages

The KFD2-SR2-Ex2.W excels in high-vibration and chemically aggressive environments through its ruggedized K-System housing and gold-plated contact terminals. Its dual-channel design offers a significant density advantage, allowing for the consolidation of digital inputs without expanding cabinet footprints. The module remains fully compatible with SIL 2 functional safety requirements, making it a trusted choice for emergency shutdown (ESD) systems and critical interlocking logic. By isolating the field side from the safe side with high-dielectric strength, the KFD2-SR2-Ex2.W effectively eliminates ground loops and protects sensitive control hardware from atmospheric electrical surges.

Delivery & Logistics

Delivery Time: 3-5 days once payment is finalized.

Shipping Carriers: Shipped via DHL, FEDEX, or UPS with original factory-sealed packaging and full tracking transparency.

Technical FAQs

Q1: How do I disable the Line Fault Detection (LFD) if I am using a simple toggle switch?

A1: You can deactivate the LFD feature by adjusting the DIP switches on the front of the module. However, for safety reasons, we recommend using resistors at the switch contact to maintain the monitoring capability.

Q2: What do the different LED colors indicate on the front panel?

A2: The Green LED indicates the module is powered. Yellow LEDs show the switching status of the output relays, and Red LEDs signal a fault condition (line break or short circuit) in the field wiring.

Q3: Can I use the KFD2-SR2-Ex2.W with 110V AC supply power?

A3: No, this specific model is a DC-powered unit (19-30V DC). If your cabinet only provides AC power, you will need to install a K-System power supply or choose the KFA6 series equivalent.

Q4: What is the significance of the ".W" suffix in this model number?

A4: The ".W" indicates that the relay outputs are change-over (Form C) contacts, providing both a normally open and a normally closed terminal for each channel, offering greater flexibility for control logic.