Pepperl+Fuchs KFD0-RO-2 | Isolated Repeater Power Supply for NAMUR Sensors, 24V DC
Pepperl+Fuchs KFD0-RO-2 isolated repeater/power supply for NAMUR proximity switches. 24V DC, 1-channel, relay output, Zone 0/1 / Div. 1, DIN rail mount, SIL 2.
Product Overview
The Pepperl+Fuchs KFD0-RO-2 (Order No. KFD0-RO-2) is an intrinsically safe isolating repeater / power supply from the KF series, designed to power and condition signals from NAMUR-type proximity switches or mechanical contacts installed in hazardous areas (Zone 0/1, Division 1). It provides an isolated relay output (1 CO contact) on the safe side and supplies the field device with a nominal 8.2 V DC / 1 kΩ NAMUR interface voltage. Commonly used to bring position feedback from Ex-i sensors (e.g., NJ2-V3-N) into non-Ex PLC inputs.
Technical Specifications (Electrical & Function)
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Parameter
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Specification
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Order Number
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KFD0-RO-2
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Function
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Isolated Repeater / Power Supply for NAMUR Sensors & Dry Contacts
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Supply Voltage (Terminals 1-2)
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20 … 30 V DC (Nominal 24 V DC)
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NAMUR Input (Terminals 3-4)
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8.2 V DC ± 5% @ 1 kΩ (IEC 60947-5-6 NAMUR)
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Switch Threshold (NAMUR)
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≤ 1.2 mA (Low / Sensor Active), ≥ 2.1 mA (High / Sensor Inactive)
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Output Type
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1 Changeover (CO / Form C) Relay Contact
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Contact Rating
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250 V AC / 2 A (Resistive), 30 V DC / 2 A
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Response Time
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≤ 20 ms (typ.)
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Galvanic Isolation
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3 kV AC (Input/Output/Supply)
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Technical Specifications (Mechanical & Certification)
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Parameter
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Specification
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Mounting
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35 mm DIN Rail (EN 60715) — snaps onto top-hat rail
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Housing Width
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12.5 mm (KF compact series)
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Connection
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Screw Terminals (Cage Clamp style)
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Operating Temperature
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-20 … +60 °C
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Protection Rating
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IP20 (Enclosed in cabinet)
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Hazardous Area Approval
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ATEX / IECEx: [Ex ia] IIC / [Ex ia] IIB+H2
FM / cCSAus: Class I Div. 1 Groups A-D
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SIL Capability
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SIL 2 (IEC 61508 / IEC 61511)
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Standards
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IEC 60079-0, IEC 60079-11, EN 50270 (EMC)
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Key Features
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NAMUR Interface Built-In: Powers NAMUR sensors (e.g., Pepperl+Fuchs NJx-V3-N) directly with the correct 8.2V/1kΩ bias — no external resistors needed.
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Galvanic Isolation: 3 kV isolation between field side, output side, and supply protects the control system from ground loops and transients.
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Relay Output for Easy Interfacing: CO (Form C) relay contact works with standard PLC digital inputs, eliminating need for additional interposing relays.
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Compact DIN Rail Footprint: 12.5 mm width conserves panel space in marshalling cabinets with many Ex-i loops.
Applications
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Hazardous Area Position Feedback: Converting NAMUR valve-position switch or proximity sensor signals from Zone 1/Div.1 into safe-area PLC DI cards.
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Intrinsic Safety Barrier: Providing Ex ia (Entity) protection for field contacts/sensors in flammable gas atmospheres.
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Signal Conditioning: Cleaning up dry-contact or NAMUR signals and providing isolated repeat for long cable runs.
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Safety Instrumented Systems (SIS): SIL 2 capable — suitable for SIF loops requiring proof-tested isolation.
Note: For 2-channel or transistor (solid-state) output versions, see KFD2-RO-2 (2-channel) or KFD0-SD-Ex1.… (solid-state). The KFD0-RO-2 is the 1-channel relay output model. Always verify the entity parameters of your NAMUR sensor match the barrier's Uo/Io/Po ratings before installation.
About ACH
Founded in 2012, ACH is a top-tier distributor of industrial automation products, supplying genuine devices from leading brands like ABB, P+F, E&H, AB, MTL to emerging markets worldwide. Our mission is to provide 100% Genuine products at the most competitive prices, helping customers reduce costs and strengthen their market position.
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Frequently Ask & Questions
Are preferential prices available?
Long-term brand partners can get competitive product prices. At the same time, ACH controls the profit per order to 5%, providing the most competitive prices.
Are the Products Genuine OEM Units?
Yes, all products from ACH are certified genuine OEM units. We acquire our inventory through official OEM channels and trusted third-party suppliers, ensuring every item is authentic and reliable.
How will you arrange shipment?
We'll handle the shipping for you. Through our partnerships, we can secure competitive rates with major carriers like FedEx, DHL, TNT, and UPS, ensuring a smooth and cost-effective delivery.
What is the warranty of goods?
One-year Warranty.
How long is the logistics cycle of the product?
Products are divided into spot and futures, and the delivery period of different brands of products is also different. For details, please contact the ACH business manager.
