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Low-frequency acceleration standard measuring device (LF acceleration standard, 0,1 Hz to 20 Hz)

Working Group 1.71

This acceleration standard is the national standard for the realization of the unit of acceleration (and the associated scale) at sinusoidal vibration of a solid body in the frequency range from 0,1 Hz to 20 Hz. 

At sinusoidal accelerations free from distortion, the measurands velocity and displacement are generated at the same time so that, in connection with the laser interferometer, the units of the three translational motion quantities (acceleration, velocity and displacement) are realized. 

The maximum displacement amplitude is 0,5 m, the maximum acceleration amplitude 2 m/s2. The amplitudes of the motion quantities are measured with a relative measurement uncertainty of 0,1 %. 

The complex sensitivity of precise accelerometers (reference and transfer standards) can be measured with a measurement uncertainty of 0,2 % (for magnitude) and 0,5° (for phase shift; primary vibration calibration by laser interferometry in accordance with ISO 16063-11). 

At frequencies of 0,5 Hz or higher, the comparison method (secondary vibration calibration in accordance with ISO 5347-3 and 16063-21) can be applied, the measurement uncertainty then being 0,5 %.

Low-frequency acceleration standard measuring device
(exciter with interferometer)

The LF acceleration standard consists of

  • Low-frequency acceleration exciter
  • Laser interferometer with interferometer signal measuring system
  • System for measuring electrical output quantities of calibration objects (voltage or charge)
  • Supply system
  • Vibration isolation system