Heschen M18 Capacitive Proximity Sensor Switch LJC18A3-B-Z/BY Instruction Manual

1. Introduction

This manual provides detailed instructions for the installation, operation, and maintenance of the Heschen M18 Capacitive Proximity Sensor Switch, model LJC18A3-B-Z/BY. This sensor is designed for reliable detection of various materials, including metals, non-metals, liquids, and powders, without physical contact.

2. Safety Information

Please read and understand all safety instructions before installing or operating the sensor. Failure to follow these instructions may result in personal injury or damage to the equipment.

• Ensure power is disconnected before performing any wiring or installation.
• Do not exceed the specified supply voltage (10-30VDC).
• Avoid installing the sensor in environments with excessive vibration, high temperatures, or corrosive gases.
• Protect wiring from mechanical damage.
• This device is not intended for safety-critical applications where malfunction could lead to severe injury or death.

3. Product Overview and Features

The Heschen M18 Capacitive Proximity Sensor is a non-shielded type sensor with a cylindrical M18 threaded body. It features a PNP Normally Open (NO) output and is designed for detecting various materials.

Key Features:

• Model: LJC18A3-B-Z/BY
• Mounting Hole Diameter: 18mm
• Detecting Distance: 10mm ±10% (Adjustable 0-8mm)
• Output Type: PNP Normally Open (NO), 3-wire
• Current Output: Max 200mA
• Working Voltage: 10-30 VDC
• Cable Length: Approximately 127cm (50 inches)
• Detection Object: Can detect any dielectric material.
• Protection: Reversal connection protection, surge absorption, load short-circuit protection.

Figure 1: Heschen M18 Capacitive Proximity Sensor Switch (LJC18A3-B-Z/BY) with its cable.

4. Components and Identification

The sensor consists of a main body, sensing head, adjustment potentiometer, and an operating indication light.

Figure 2: Rear view of the sensor showing the operating distance adjustment potentiometer and the operating indication light.

• Operating Distance Adjusting Potentiometer: Used to fine-tune the detection range of the sensor.
• Operating Indication Light (LED): Illuminates when an object is detected within the set range.
• Power Wire: The cable extending from the sensor for electrical connection.

5. Setup and Installation

5.1 Mounting

The sensor features an M18 threaded body for panel mounting. Secure the sensor using the provided clamp nuts and buckle washer.

Figure 3: Detailed dimensions of the sensor, including the M18 thread, clamp nut, and buckle washer for mounting.

• Drill an 18mm diameter hole for mounting.
• Insert the sensor and secure it with the two clamp nuts and buckle washer.
• Ensure the sensor head is positioned correctly relative to the target detection area.
• This is a non-shielded (non-flush) type sensor, meaning it can be mounted with the sensing face extending beyond the mounting surface.

5.2 Wiring

The LJC18A3-B-Z/BY is a 3-wire PNP Normally Open (NO) sensor. Connect it to a DC power supply (10-30VDC) and your control circuit as follows:

Figure 4: Wiring diagram showing the connection of the brown, black, and blue wires for the PNP Normally Open sensor.

• Brown (BN): Connect to the positive (+) terminal of the DC power supply (10-30VDC).
• Blue (BU): Connect to the negative (-) terminal of the DC power supply.
• Black (BK): This is the signal output wire. Connect it to the input of your control device (e.g., PLC, relay). For a PNP NO sensor, the black wire will output a positive voltage (close to VCC) when an object is detected.

Ensure all connections are secure and insulated to prevent short circuits.

5.3 Detection Distance Adjustment

The detection distance can be adjusted using the potentiometer located at the rear of the sensor (refer to Figure 2). Rotate the potentiometer clockwise to increase the detection distance and counter-clockwise to decrease it. Test the detection range with your target object after adjustment.

6. Operating Instructions

Once properly installed and wired, the sensor operates automatically. When a target object enters the detection field, the sensor's output will change state, and the operating indication light will illuminate.

• Normally Open (NO) Operation: In the absence of a detected object, the output (black wire) is OFF (low impedance or open). When an object is detected, the output turns ON (provides a positive voltage).
• Detection of Materials: This capacitive sensor can detect a wide range of materials, including liquids, powders, and various solids, based on their dielectric properties. The detection distance may vary depending on the material and its size.

Figure 5: Graphs illustrating the relative detection sensitivity for different materials (e.g., Iron, Stainless Steel, Brass, Aluminum, Copper) and how the size of the detecting object affects the stable detection distance.

As shown in Figure 5, materials with higher dielectric constants (like iron) are generally detected more easily and at greater distances than materials with lower dielectric constants (like copper). The detection distance also stabilizes once the object size exceeds a certain threshold.

7. Maintenance

The Heschen M18 Capacitive Proximity Sensor is designed for long-term, maintenance-free operation under normal conditions.

• Keep the sensing face clean and free from excessive dust, dirt, or moisture, which can affect detection performance.
• Periodically check wiring connections for tightness and integrity.
• Avoid exposing the sensor to harsh chemicals or abrasive cleaning agents.

8. Troubleshooting

9. Technical Specifications

10. Warranty and Support

For warranty information and technical support, please contact your Heschen product supplier or refer to the official Heschen website. Keep your purchase receipt for warranty claims.

For further assistance, you may visit the Heschen store online: Heschen Store.