SICK KT8L Series Contrast Sensor Instruction Manual

1. Introduction

The SICK KT8L series contrast sensors are advanced photoelectric sensors designed for reliable detection of contrasts, such as print marks, labels, or color differences on various materials. These sensors utilize a red laser light source and offer precise detection capabilities essential for industrial automation applications. This manual provides detailed instructions for the proper setup, operation, maintenance, and troubleshooting of your SICK KT8L contrast sensor.

2. Setup

2.1 Mounting

The SICK KT8L sensor features a robust rectangular zinc diecast housing. Refer to the dimensional drawing below for precise mounting hole locations and overall dimensions. The sensor can be securely mounted using M5 screws.

• Dimensions (W x H x D): 30.4 mm x 53 mm x 80 mm
• Housing Design: Rectangular
• Light Emission: Long side of housing

2.2 Electrical Connection

The sensor is equipped with a male M12, 5-pin connector for electrical connection. Ensure the power supply is within the specified range of 10 V DC to 30 V DC. Connect the wires according to the pin assignment provided below and illustrated on the sensor's label.

Circuit Protection: The sensor features UV connections with reverse polarity protection, short-circuit protected output Q, and interference pulse suppression.

3. Operating Instructions

3.1 Teach-in Procedure

The SICK KT8L sensor can be adjusted using its integrated teach-in button or via the external teach-in input (ET). Two main teach-in modes are available:

• Static 2-point Teach-in: This mode is used for teaching two distinct contrast levels. First, present the background or first contrast to the sensor and activate the teach-in function (e.g., by pressing the button or applying a signal to ET). Then, present the mark or second contrast and activate teach-in again. The sensor will learn the difference between these two points.
• Dynamic Teach-in (Min/Max): This mode is suitable for teaching contrasts on moving objects. While the object (containing both contrasts) passes the sensor, activate the teach-in function. The sensor will automatically detect and store the minimum and maximum contrast values encountered during the teach-in period.

Retention Time (ET): 25 ms, with non-volatile memory for learned settings.

Time Delay: 20 ms, adjustable.

3.2 Sensing and Detection

• Sensing Distance: The optimal sensing distance is 150 mm from the front edge of the lens.
• Operating Distance: The effective operating range is 30 mm to 800 mm, with respect to black-white contrast of 6% / 90%.
• Light Source: Red laser with a wavelength of 655 nm. The average service life of the laser is 50,000 hours at 25 °C.
• Light Spot Size: The light spot has a diameter of Ø 0.3 mm at the focal point (150 mm sensing distance).
• Automatic Drift Correction: The sensor is equipped with an automatic drift correction function to ensure stable and consistent detection performance over time, compensating for minor environmental changes.

4. Maintenance

To ensure the longevity and optimal performance of your SICK KT8L contrast sensor, follow these maintenance guidelines:

• Cleaning: Keep the sensor lens and housing clean. Use a soft, lint-free cloth, possibly dampened with a mild cleaning solution, to remove dust, dirt, or debris. Avoid abrasive materials or harsh chemicals that could damage the lens or housing.
• Connection Check: Periodically inspect all electrical connections for tightness and integrity. Ensure there are no signs of corrosion or wear on the M12 connector or cables.
• Environmental Conditions: Verify that the sensor operates within the specified ambient temperature and humidity ranges to prevent damage and ensure reliable function.
• Physical Inspection: Check the sensor for any physical damage, such as cracks in the housing or lens, which could affect its performance or enclosure rating.

5. Troubleshooting

If you encounter issues with your SICK KT8L contrast sensor, refer to the following troubleshooting steps:

5.1 No Power / Indicator Light Off

• Check Supply Voltage: Ensure the sensor is receiving a stable 10 V DC to 30 V DC power supply.
• Verify Wiring: Confirm that the L+ (Brown wire) and M (Blue wire) connections are correctly wired and secure.

5.2 No Output / Incorrect Sensing

• Re-perform Teach-in: The most common solution is to repeat the teach-in procedure (Static 2-point or Dynamic) to ensure the sensor has correctly learned the desired contrast levels.
• Check Sensing Distance: Ensure the target object is within the optimal sensing distance of 150 mm and the operating range of 30 mm to 800 mm.
• Contrast Levels: Verify that the contrast difference between the mark and background is sufficient (e.g., at least 6% / 90% black-white contrast).
• Lens Condition: Inspect the sensor lens for any obstructions, dirt, or damage that might interfere with light emission or reception.
• Output Wiring: Check the connections for the switching output (Q - Black wire) and analog output (QA - White wire) to ensure they are correctly wired to your control system.

5.3 Intermittent Operation

• Environmental Stability: Ensure the sensor is not subjected to excessive vibrations or shock loads beyond IEC 60068 standards.
• Power Supply Ripple: Check that the power supply ripple is ≤ 5 Vpp to maintain stable operation.
• Target Stability: Ensure the target object's position and presentation are consistent during operation.

6. Specifications

7. User Tips

• Optimal Mounting: For best results, mount the sensor securely to minimize vibrations and ensure the target object passes consistently within the recommended operating distance.
• Teach-in Accuracy: When performing the teach-in procedure, ensure a clear and stable presentation of both contrast levels to maximize detection accuracy.
• Small Mark Detection: Due to the small light spot size (Ø 0.3 mm), this sensor is well-suited for detecting small marks or fine details. Position it carefully to align the light spot with the feature of interest.
• Environmental Consistency: Maintain consistent lighting and environmental conditions around the sensor to prevent false readings, although the automatic drift correction helps mitigate minor changes.

8. Warranty and Support

For any technical assistance, warranty claims, or further inquiries regarding your SICK KT8L contrast sensor, please contact the seller or manufacturer directly. Keep your purchase records handy for faster service.

You may reach support via the following channels:

• WhatsApp: +86 181 5273 9781
• Email: dy31631415926@126.com