AC Two-Wire Inductive Proximity Sensors

Product Introduction

The DAIDISIKE AC two-wire inductive proximity sensor series is a non-contact metal detection device for industrial automation, including M12, M18, and M30 models. It supports AC two-wire power supply and detects metals like iron, steel, and aluminum. The brand is known for high reliability, durability, and cost-effectiveness, widely used in mechanical manufacturing, assembly lines, robotic arms, and conveyor systems. Sensors feature nickel-plated brass housing with IP67 protection for stable operation in harsh environments like humidity, dust, or vibration. Outputs include NO/NC for easy PLC integration. Two-wire design simplifies wiring and reduces costs while maintaining precision. Key advantages: 2-15mm sensing range, LED indicators, short-circuit and reverse polarity protection. Compliant with CE and RoHS standards, offering 2-meter cable or M12 connector options, with flush/non-flush mounting for optimized performance. This series is waterproof, ensuring reliable operation in moist environments.

Specifications Table

The following is a detailed specifications table for the DAIDISIKE AC two-wire inductive proximity sensor series, organized by size:

Note: Specifications may vary slightly by specific model; please refer to the product manual for exact values. Sensing distance is for standard iron targets (size twice the sensing distance). This series features waterproof design.

Technical Parameters

The technical parameters of the DAIDISIKE AC two-wire inductive proximity sensors are as follows, ensuring high performance and reliability in industrial environments:

• Supply Voltage Range: 20-250V AC, 50/60Hz, supporting wide voltage input for most industrial AC power systems.
• Leakage Current: ≤1.7mA, ensuring low power consumption and efficiency.
• Voltage Drop: ≤7V, ensuring stable output under load.
• Hysteresis: 3-20% of sensing distance, preventing false triggers and improving detection accuracy.
• Temperature Drift: ≤±10% (within -25°C to +70°C range), adapting to temperature variations.
• Shock and Vibration Resistance: Compliant with IEC 60947-5-2, vibration 10-55Hz, shock 30g.
• Electromagnetic Compatibility: Anti-EMI, compliant with EN 61000 standards.
• Sensing Head Material: PBT plastic, resistant to corrosion and mechanical damage.
• LED Indication: Yellow LED for output status display, convenient for on-site debugging.
• Short-Circuit Protection: Built-in, preventing overload damage.
• Reverse Polarity Protection: Yes (adapted for AC), ensuring installation errors do not damage the sensor.
• Response Time: ≤20ms, suitable for medium-speed applications.
• Target Material: Ferromagnetic and non-ferromagnetic metals, with correction factors for different materials (e.g., stainless steel 0.7, aluminum 0.4).
• Protection Features: Waterproof (IP67), suitable for humid and dusty environments.
• Lifespan: Over 10^7 operations, with no mechanical wear.

These parameters are based on industry standards and verified through rigorous testing, ensuring long-term stable operation of DAIDISIKE sensors in automated production lines.

Working Principle

The working principle of the DAIDISIKE AC two-wire inductive proximity sensor is based on electromagnetic induction. Specifically, the sensor contains a high-frequency oscillation circuit internally, which generates an alternating magnetic field. When a metal object (target) enters the sensor's sensing area, eddy currents are induced in the target, altering the impedance and amplitude of the oscillation circuit. The sensor detects this change and, through an internal amplifier and comparator circuit, converts the signal into a switch output.

Detailed process:

1. Oscillator Generates Magnetic Field: The front-end coil of the sensor produces a high-frequency magnetic field (typically several hundred kHz).

2. Target Approaches: The metal object enters the magnetic field, absorbs energy, and generates eddy currents, causing field attenuation.

3. Detects Change: The oscillator's amplitude or frequency change is captured by the detection circuit.

4. Signal Processing: Through threshold comparison, outputs a switch signal (NO or NC).

5. Two-Wire Design: Power and signal are transmitted via the same pair of wires, simplifying the circuit; the load is connected in series in the power loop, and when the sensor activates, current changes drive the load. Since it is AC-powered, the sensor accommodates alternating current supply, with output directly switching the AC load.

This non-contact detection avoids mechanical wear, enhancing lifespan (typically over 10^7 operations). In professional terms, this is an "Inductive Proximity Sensor," compliant with IEC 60947-5-2 standards, commonly used for "Position Sensing" and "Presence Detection." Compared to DC versions, AC two-wire sensors are better suited for high-voltage environments and offer stronger resistance to electrical noise, though with lower switching frequencies. The core of detection is energy transfer via eddy current losses, applicable to ferromagnetic and non-ferromagnetic metals.

Specs reviewed by Engineer Cai, Senior Application Engineer. CE & RoHS compliant — see certificates.