The Pepperl+Fuchs KFD2-SR2-Ex2.W is a high-performance 2-channel isolated barrier functioning as a switch amplifier for proximity sensors and mechanical contacts. This model operates with a 24 V DC supply via Power Rail or direct terminals, making it ideal for space-saving cabinet installations.
This switch amplifier accepts input from dry contacts or NAMUR proximity switches (acc. to EN 60947-5-6) located in hazardous zones across two independent channels. It then provides two separate relay contact outputs for safe-area control systems. Furthermore, the KFD2-SR2-Ex2.W includes line fault detection (LFD) on each channel to monitor for broken wires or short circuits, enhancing diagnostic capabilities. Its reversible mode of operation allows independent configuration for normally open or normally closed behavior per channel.
The KFD2-SR2-Ex2.W is engineered with precise electrical characteristics to ensure dependable dual-channel switching performance in demanding environments.
Number of Channels: 2 independent channels.
Input Type: Dry contact or NAMUR proximity switches (acc. EN 60947-5-6).
Terminals: Channel I: 1+, 2+, 3-; Channel II: 4+, 5+, 6-.
Open Circuit Voltage: approx. 8 V DC.
Short-Circuit Current: approx. 8 mA.
Switching Point: 1.2 ... 2.1 mA with a hysteresis of approx. 0.2 mA.
Pulse/Pause Ratio: Minimum 20 ms / 20 ms for reliable signal detection.
Line Fault Detection: Breakage detected when I ≤ 0.1 mA; short-circuit detected when I > 6 mA.
Output Type: Relay contact output per channel.
Terminals: Output I: 7, 8, 9; Output II: 10, 11, 12.
Contact Loading: 250 V AC / 2 A (cos φ > 0.75); 126.5 V AC / 4 A (cos φ > 0.75); 40 V DC / 2 A resistive.
Minimum Switch Current: 2 mA / 24 V DC.
Energised/De-energised Delay: approx. 20 ms each.
Mechanical Life: 10⁷ switching cycles, ensuring long-term reliability.
Collective Error Message: Available via Power Rail connection.
Switching Frequency: ≤ 10 Hz.
Rated Voltage: 19 ... 30 V DC (nominal 24 V DC).
Ripple: ≤ 10 % within supply tolerance.
Rated Current: ≤ 50 mA.
Power Consumption: ≤ 1 W, with power dissipation of ≤ 1 W.
Safety integrity is a core feature of this dual-channel switch amplifier. Consequently, the Pepperl+Fuchs KFD2-SR2-Ex2.W is certified up to SIL 2 (SC 3) according to IEC/EN 61508.
Moreover, it carries extensive hazardous area approvals:
ATEX: [Ex ia Ga] IIC, [Ex ia Da] IIIC, [Ex ia Ma] I for inputs; Ex ec nC IIC T4 Gc for outputs.
FM & UL: Approved for installation in Division 2 environments.
IECEx: [Ex ia Ga] IIC and Ex ec nC IIC T4 Gc.
The reinforced insulation between input, output, and power supply provides rated insulation voltage of 300 Veff according to IEC/EN 61010-1, with safe electrical isolation of 375 V peak according to IEC/EN 60079-11.
Configuration of the KFD2-SR2-Ex2.W is simple and flexible via DIP switches. Specifically, you can independently set the mode of operation (normally open or normally closed) for each channel. Additionally, the line fault detection (LFD) feature can be switched off per channel if not required.
The front-panel LEDs provide clear visual status indication for each channel. During a fault condition (wire break or short circuit), the relay reverts to its de-energized state and the LEDs indicate the fault according to NAMUR NE 44. If the device is operated via Power Rail, a collective error message is also available for remote diagnostics.
This device is built to withstand harsh industrial conditions.
Ambient Temperature: -40 ... 70 °C (-40 ... 158 °F), offering extended temperature range.
Degree of Protection: IP20.
Dimensions: 20 x 119 x 115 mm (0.8 x 4.7 x 4.5 inch) - Housing type B2.
Mass: approx. 150 g, lightweight for DIN rail mounting.
Mounting: Standard 35 mm DIN mounting rail acc. to EN 60715.
Installing the KFD2-SR2-Ex2.W is a straightforward process. Begin by mounting the unit on a 35 mm DIN rail inside a control cabinet. Next, connect the 24 V DC power supply via the Power Rail or terminals 14+ and 15-.
For the input side, wire the NAMUR sensors or dry contacts to the respective channel terminals. Channel I connects to terminals 1+, 2+, and 3-; Channel II connects to terminals 4+, 5+, and 6-. Similarly, connect the relay outputs to terminals 7, 8, 9 (Output I) and 10, 11, 12 (Output II) according to your control logic requirements.
Use the DIP switches to configure the reversible mode of operation and line fault detection for each channel independently. The integrated labeling space at the front allows for clear identification in multi-device cabinets.
Each unit is carefully packaged to ensure safe delivery.
Packaging List:
1 x KFD2-SR2-Ex2.W Switch Amplifier
1 x Labeling Set for front panel marking
1 x Installation Instructions (Digital Download)
Shipping Methods: Fedex, UPS, DHL
Q1: What is the main difference between the KFD2-SR2-Ex2.W and the single-channel version?
A: The KFD2-SR2-Ex2.W provides two independent channels in one housing, saving cabinet space and reducing installation cost compared to using two single-channel units.
Q2: What types of input devices can I connect to each channel?
A: Each channel of the KFD2-SR2-Ex2.W supports both dry mechanical contacts and NAMUR proximity sensors (acc. to EN 60947-5-6) located in hazardous areas.
Q3: How does the line fault detection (LFD) work on this device?
A: The LFD continuously monitors each input circuit independently. It detects a wire break when the current drops to ≤ 0.1 mA and identifies short circuits when current exceeds 6 mA, providing valuable diagnostic feedback per channel.
Q4: Can I use this unit for SIL-rated safety applications?
A: Yes, this switch amplifier is certified for functional safety up to SIL 2 (SC 3) according to IEC/EN 61508, making it suitable for safety-related control loops.
Q5: What happens during a fault condition?
A: During a fault condition, the affected channel's relay reverts to its de-energized state. The front LEDs indicate the specific fault according to NAMUR NE 44, and a collective error message is available via the Power Rail connection for remote monitoring.
| Brand Name | Pepperl+Fuchs |
| Model No. | KFD2-SR2-EX2.W |
| Product Type | Switch Amplifier |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
