Product Description

The CSU-1001-PXI AC/DC Capacitive Sensor Unit (CSU) is a fully integrated analog synchronous modulation/demodulation system that provides the ability to measure mean and fluctuating quantities of interest, e.g., wall shear stress or pressure, using a capacitive sensor. The CSU provides low-noise power to the sensor head and conditions the analog voltage signal received from the sensor head for output to a data acquisition system. Capacitive sensing at DC is achieved by shifting the sensor baseband frequencies to a modulated signal and demodulating the returned signal from the sensor, enabling simultaneous real-time measurement of both mean and dynamic components.

Features and Benefits

  • Ability to measure mean and fluctuating quantities using a variety of capacitive devices
  • Integrated rechargeable lithium-ion battery system minimizes power line noise
  • Multi-pin shielded sensor connector provides supply voltages and carrier signals
  • System status and battery voltage LED indicators

Additional Required Equipment

  • The following additional components and specifications are recommended for AC and DC testing/calibration with the capacitive sensor control unit:
  • CSU-compatible capacitive sensor head and cable
  • RG58 coaxial cable with BNC connectors
  • Data acquisition system (DAQ) – ac/dc measurement
    • Sensing Range: ±1, ±5, ±10V – sensor dependent (see datasheet)
    • Resolution: 18+ bits
    • Sampling frequency:
      • Sensor dependent w/ analog filter between sensor output and analog-todigital converter (ADC)
      • 100+ kS/s w/o analog filter
  • Digital multimeter – DC measurement only
    • 6.5 digits with power line cycle (PLC) integration
    • o DAQ or PC connection (e.g., GPIB)