Electronic vibration sensor AKF392

MEMScapacitivefor machine monitoring

Product description
The AKF392 family is a three-axis MEMS digital vibration sensor series developed with Swiss-patented technology. The sensors provide digital outputs (RS232 / RS485 / TTL), configurable address codes and the ability to chain multiple units for long-distance multi-point measurement and centralized data analysis. Each sensor integrates a single-crystal silicon capacitive MEMS chip, a low-power ASIC for signal conditioning, a microcontroller for compensation storage and an internal temperature sensor. The device offers low power consumption, factory calibration, solid mechanical design and full protections including solid-state reset power and over-current protection. Scale factor long-term stability and bias typical values are below 0.1% across the full range, ensuring reliable outputs for industrial monitoring applications.

Key features

• Three-axis measurement: X, Y, Z
• Digital outputs: RS232 / RS485 / TTL
• Supply voltage: 9–36 VDC, current <60 mA @12 V
• Selectable measurement ranges: ±2, ±4, ±8, ±10, ±20, ±40 g
• Bandwidth (3 dB): 500 Hz
• Shock & impact resistance up to specified limits (short shocks up to 2000 g noted)
• Operating temperature: -40°C to +85°C
• Industry-standard M12 connector; compact 34.3 × 34.3 × 38.5 mm housing

Scope of application

• Crash recording, fatigue monitoring and prediction
• Wind-turbine monitoring and condition assessment
• Traffic infrastructure monitoring, railway subgrade analysis and high-speed rail fault detection
• Large rotating machinery and engine monitoring
• Low-frequency vibration and automated monitoring systems
• Medical devices monitoring
• Bridge structural health monitoring
• Vehicle (automotive) vibration monitoring
• Roller and rotating equipment monitoring

Parameters
Model family: AKF392 (example variant: AKF392T)
Ranges: ±2 g | ±4 g | ±8 g | ±10 g | ±20 g | ±40 g
Bias calibration: <1 mg (all ranges)
Axes: X, Y, Z (triaxial)
Power on/off repeatability: <2 mg (max)
Temperature coefficient of bias: 0.01 %/°C (typical)
Resolution / threshold (@1 Hz): <1 mg (max)
Nonlinearity: <0.5% / <0.8% / <1% FS (depending on range)
Bandwidth (3 dB): 500 Hz
Cross-axis sensitivity: 1% / 2% (depends on range)
Lateral vibration sensitivity ratio: 1% / 2% / 5% (depends on range)
Noise density: 21 μg/√Hz or 86.6 μg/√Hz (depending on range)
Resonance frequency: 2.4 kHz or 5.5 kHz (depending on range)
Output rates: 68-protocol: 5–1000 Hz selectable; MODBUS: 10/25/50 Hz
Output interfaces & protocols: RS232 / RS485 / TTL — Rion 68 protocol and Modbus RTU
Reliability: MIL-HDBK-217 Grade 2
Shock resistance: 100 g @ 11 ms (half sinusoid, 3 axes)
Recovery time: <1 ms (example: 1000 g, 1/2 sin 1 ms on one axis)
Vibration tolerance: 20 g RMS, 20–2000 Hz (per axis, 30 min random)
Supply: 9–36 VDC; current <60 mA @12 VDC
Connector: M12 industry standard
Weight: sensor 82 g; magnetic base 48 g; L-adapter 20 g
Dimensions: sensor 34.3 × 34.3 × 38.5 mm; magnetic base 34.23 × 34.23 × 6 mm; L-adapter 36 × 44 × 15 mm

Technical specifications

• Sensor type: single-crystal silicon capacitive MEMS accelerometer (digital)
• Measurement axes: triaxial X, Y, Z
• Selectable full-scale ranges to ±40 g
• Bandwidth: 500 Hz (3 dB)
• Resonance frequency: ~2.4 kHz (low ranges) / ~5.5 kHz (high ranges)
• Noise density and resolution suitable for low-frequency monitoring
• Digital communication: Rion 68 protocol and Modbus RTU over RS232/RS485/TTL
• Robust mechanical housing, factory-calibrated for industrial monitoring