SICK WFS3-40B41CA70 3 mm Push-Pull Fork Sensor – Label Detection Solution

Overview:

• Fork gap: 3 mm, fork depth: 42 mm – optimized for label, thin film, and small object detection on high-speed production lines.
• Output: Push-pull PNP/NPN, supply voltage 10…30 V DC – easy integration with both legacy and modern PLC systems.
• IO-Link V1.1 support – enables remote monitoring, parameter configuration, and real-time diagnostics without production interruption.
• Response time: ≤ 46 µs, switching frequency 15 kHz – ideal for high-speed packaging lines.
• Protection rating: IP65, operating temperature –20 °C to +60 °C – robust for industrial environments.
• Dynamic Teach-in function automatically optimizes thresholds for different label materials.

The SICK WFS3-40B41CA70 (fork sensor) is an optical fork sensor from SICK’s WFS series, specifically engineered for reliable detection of labels, tags, and thin objects on conveyors. With a narrow 3 mm slot, Push-pull PNP/NPN output, and IO-Link V1.1 integration, it is the ideal solution for labeling machines, printing, and automated packaging lines in Vietnam.

Overview of the SICK WFS3-40B41CA70 Fork Sensor

The WFS3-40B41CA70 belongs to SICK’s WFS fork sensor family, developed for high-precision label detection and material differentiation in the packaging, labeling, and electronics manufacturing industries.

Unlike conventional photoelectric sensors, the WFS3-40B41CA70 uses an infrared LED emitter and receiver housed in a single fork body, eliminating alignment errors and enabling detection of objects as small as 2 mm (gap between labels). It supports three teach-in modes: 1-point, 2-point, and dynamic teach-in, allowing quick setup without external measurement tools.

Additionally, IO-Link V1.1 enables remote monitoring of sensor status, adjustment of output delay times, selection of light/dark switching, and button lock functions directly from a PLC or SCADA system — perfectly suited for Industry 4.0 implementations.

5 Key Highlights:

• Fork slot: 3 mm width, 42 mm depth – detects labels from 2 mm gaps.
• Output: Push-pull PNP/NPN, max 100 mA, 10…30 V DC.
• IO-Link: V1.1, cycle time 2.3 ms, Vendor ID 26.
• Response time: ≤ 46 µs, switching frequency 15 kHz.
• Protection: IP65, glass-fiber reinforced PA housing, weight ~36 g.

Technical Specifications – WFS3-40B41CA70

Note: Do not bend cable at temperatures below 0 °C.

Source: Official SICK datasheet (updated 2026-03-12).

Download Datasheet

Ordering Information

See full WFS series and accessories at: www.sick.com/WFS

Industrial Applications

Thanks to its 3 mm slot and 2 mm minimum object detection capability, the WFS3-40B41CA70 is widely used in high-precision applications:

Label Detection on Rolls

Specialized for detecting labels on label webs. The focused infrared LED reliably distinguishes between label material (paper/PP) and liner based on light transmission differences. Dynamic teach-in allows threshold optimization while the line is running.

High-Speed Labeling Machines

Positioned at the label dispenser output to count dispensed labels and verify correct positioning before application. 15 kHz switching frequency ensures no missed labels even at maximum line speeds.

Thin Material Detection in Electronics & Semiconductor

Confirms presence of films, carrier tapes, PCBs, and thin documents in automated handling and packaging processes.

Paper Position Control in Printing & Cutting Machines

Monitors paper position and end-of-roll conditions. Ultra-fast response time (≤ 46 µs) enables immediate machine stop or auto-feed activation.

IIoT / Industry 4.0 Integration via IO-Link

IO-Link V1.1 allows central controllers to read real-time light intensity values, adjust parameters, and receive predictive maintenance alerts (Quality of Run Alarm), significantly reducing unplanned downtime.

Installation & Teach-in Guide

The WFS3-40B41CA70 supports three teach-in modes:

• 1-Point Teach-in: Insert object into slot and press teach button.
• 2-Point Teach-in: Teach background and object levels separately — recommended for low-contrast materials.
• Dynamic Teach-in (recommended for labels): Press and hold teach button > 3 seconds, run at least 3 labels through the slot. LED flashes at 3 Hz during learning. Release within 20 seconds.

Fine Adjustment: Within 10 seconds after successful teach-in, press the button briefly to shift the threshold closer to the target object, increasing operating reserve.

Button Lock: Press and hold teach button > 30 seconds to lock/unlock. Can also be locked remotely via IO-Link.

Compatible Accessories

Frequently Asked Questions (FAQ)

Q1: What is the price of the WFS3-40B41CA70?

A: Price depends on quantity and project conditions. Please contact AUMI for the best quotation.

Q2: What is the minimum label thickness the sensor can detect?

A: It reliably detects label gaps as small as 2 mm. For thinner labels, dynamic teach-in is recommended to optimize differentiation between label and liner.

Q3: Does it require an external amplifier?

A: No. The amplifier is built-in. It provides direct Push-pull PNP/NPN output (100 mA) for direct connection to PLCs or IO-Link systems.

Q4: What are the benefits of IO-Link compared to standard operation?

A: In standard mode, it functions as a conventional ON/OFF sensor. With IO-Link, the system can access real-time light intensity values, quality diagnostics, parameter adjustments, and predictive maintenance data remotely.

Q5: Where can I buy genuine SICK WFS3-40B41CA70 in Vietnam?

A: AUMI is an official distributor of SICK in Vietnam. We provide 100% genuine products with full traceability, CO/CQ certificates, official warranty, and 24/7 technical support.

Contact for Purchase & Technical Support

AUMI – Official SICK Distributor in Vietnam

📞 Hotline: 0917 991 589 (Hanoi) | 0932 226 100 (Ho Chi Minh City)

📧 Email: [email protected]

🌐 Website: https://aumi.com.vn/

Addresses:

• Hanoi: B44, Viet Hung Urban Area, Long Bien
• Ho Chi Minh City: 2nd Floor, HS Building, 260/11 Nguyen Thai Binh, Tan Binh District
• Da Nang: 9th Floor, PV Bank Building, 2 30-4 Street, Hoa Cuong Ward

🔗 [Official Datasheet]

🔗 [All SICK Products at AUMI]

🔗 [Other SICK Fork Sensors]