This standard specifies the detailed requirements, instruments and calibration methods for low-frequency vibration calibration using laser interferometry. This standard applies to linear motion sensors, and its applicable scope is as follows: frequency range 0.1~100Hz dynamic range (depending on the vibration frequency): displacement: 10μm~40mm; acceleration: 0.1~100m/s2. Uncertainty: reference point uncertainty: ≤0.5%; total uncertainty: ≤1%. GB/T 13823.11-1995 Calibration method for vibration and shock sensors Laser interferometry low-frequency vibration one-time calibration GB/T13823.11-1995 Standard download decompression password: www.bzxz.net
This standard specifies the detailed requirements, instruments and calibration methods for low-frequency vibration calibration using laser interferometry. This standard applies to linear motion sensors, and its applicable range is as follows: Frequency range 0.1~100Hz Dynamic range (depending on the vibration frequency): Displacement: 10μm~40mm; Acceleration: 0.1~100m/s2. Uncertainty: Reference point uncertainty: ≤0.5%; Total uncertainty: ≤1%.

National Standard of the People's Republic of China
Calibration Methods of Vibration and Shock Pick-ups
Methods for the calibration of vibration and shock pick-upsPrimary vibration calibration by laser interferometryat low frequencies
1 Subject content and scope of application
GB/T 13823.11- 1995
This standard specifies the detailed requirements, instruments and equipment used for low-frequency vibration calibration by laser interferometry and the calibration method. This standard applies to linear motion sensors, and its applicable scope is as follows: Frequency range: 0.1～100 Hz.
Dynamic range (depending on vibration frequency): Displacement: 10 μm~40 mm;
Acceleration: 0.1~100m/s.
Uncertainty:
Reference point uncertainty: ≤0.5%;
Total uncertainty: ≤1%.
2 Reference standards
GB/T13823.1 Calibration method of vibration and shock sensors Basic concepts
GB/T13823.2 Calibration method of vibration and shock sensors 3 Environmental conditions
Temperature: 20℃±5℃.
Relative humidity: ≤75%.
4 Instruments and equipment
4.1 Vibration generator system
4.1.1 Vibration table
Acceleration waveform distortion: ≤3%.
Signal-to-noise ratio: should be greater than or equal to 60dB at full power output. Laser interferometry vibration absolute calibration (one-time calibration) Acceleration amplitude stability: During the test, the amplitude change is less than or equal to (.1% of the reading. The strain of the sensor base caused by the mounting surface should not affect the calibration sensitivity. The lateral, bending and swing accelerations should be kept to a minimum; at the calibration frequency point, the maximum is 5% of the axial movement. 4.1.2 Signal generator
Frequency range: 0.01~1000Hz.
Approved by the State Administration of Technical Supervision on April 2, 1995 586
Implementation on February 1, 1996
GB/T 13823.11—1995
Uncertainty: The limit error of a given frequency, the maximum is 0.01% of the reading. Frequency stability: Less than or equal to 0.01% of the reading during the test period. Amplitude stability: Less than or equal to 0.01% of the reading during the test period. 4.2 Installation foundation
The vibration table and laser interferometer are combined on the same foundation, the mass of which is at least 2000 times the mass of the moving part of the vibration table (including the central fixture and the sensor) to reduce the foundation. Relative motion caused by the reaction force of the foundation. Vibration isolation should be used to minimize the influence of ground surface vibration. 4.3 Laser interferometer
4.3.1 Argon-hydrogen laser
Wavelength: 0.6328μm.
4.3.2 Photoelectric converter of interferometer
Frequency range: DC～15MHz.
Signal-to-noise ratio: ≥40dB.
4.4 Frequency ratio counter
Frequency range: 0.01Hz～10 MHz.
Uncertainty: 0.01% of the most artificial reading. 4.5 True RMS voltmeter
Frequency range: 0.1～1000Hz.
Uncertainty ≤0.1%.
In the measurement, multiply the reading value of the voltmeter by √2 to obtain the single peak value. 4.6 Distortion measurement device
Frequency range: 0.1Hz～10kHz.
Measurement range: 0~10%.
Uncertainty of reading: ≤10%.
When using a spectrum analyzer to measure distortion, pay attention to reading no less than the 10th harmonic component. 4.7 Oscilloscope
Used to observe the waveform of the sensor output signal. Frequency range: DC～1000H z.
5 Other requirements
The sensor and signal conditioner should be considered as a whole during calibration; try to eliminate the DC output of the sensor signal conditioner. 6 Recommended amplitude and frequency
For displacement sensor calibration, the following amplitude and frequency points are preferably selected: displacement: 0.1.0.5.1.0,2.0.5.0,10,20mm. Frequency: 0.5,1.0,2.0,5.0,10,20,40,80Hz.For acceleration sensor calibration, the following amplitude and frequency points are preferably selected: acceleration: 0.51,2,5.10,20,50,100m/s2 frequency: 0.5,1.0,2.0,4.0,8.0,16,20,10.,80 Hz. 7 Calibration method
7.1 Calibration steps
7.1.1 Adjust the interferometer to the best working state, aim the test beam at the center of the table as much as possible, and its signal-to-noise ratio meets the requirements of 1.3.2. The sensor to be calibrated 587
GB/T13823.11-1995
should be installed in the center of the table as much as possible; if it cannot be placed in the center, a balancing mass block symmetrical to the sensor to be calibrated should be configured to reduce the lateral movement of the table. The system diagram is as follows: Frequency ratio counter
Frequency generator
Power amplifier
Reference mirror
Reflector
Vibration table
Photoelectric converter
Interferometer
Sensor
Adjustment instrument
Laser
Electronic watch
Sharpness meter
Dong wave device
Laser interferometry low frequency vibration calibration device Figure 7.1.2, check the distortion, noise and lateral vibration of the sensor at the calibration frequency point and amplitude, which should meet the requirements specified in 4.1.1. 7.1.3 First determine the reference sensitivity of the sensor to be calibrated. For the acceleration sensor, the preferred reference amplitude is 10m/s (the first reference point is 1.0m/s\); and the frequency can be preferably selected as 8Hz (the second selection point is 1Hz). Then determine its sensitivity at other calibration amplitudes and frequency points and give the percentage deviation compared with the reference sensitivity as the calibration result. 7.2 Calibration results
The ratio R between the interference frequency and the vibration frequency measured by the frequency ratio counter can be used to calculate the displacement value of the vibration according to formula (1): D
Where: 1-nitrogen-chlorine laser wavelength, which is 0.6328μm; R, --- the ratio of laser interference frequency to vibration frequency. ·Ry
If it is a displacement sensor, the displacement sensitivity S is calculated according to formula (2): Sa
If it is a velocity sensor, the velocity sensitivity S is calculated according to formula (3): V
2 yuan fD
If it is an acceleration sensor, the acceleration sensitivity S. Calculate according to formula (4): Sa
Where: V--single peak voltage output by the sensor, V; f--frequency value of vibration calibration, Hz. www.bzxz.net
.（4）
When providing a calibration result report, the total uncertainty should be calculated based on Appendix A (Supplement) and the specified confidence level. The specified confidence level is 99% (the second choice point is 95%). 588
A1 Calculation of total uncertainty
GB/T13823.11- -1995
Appendix A
Calculation of uncertainty
(Supplement)
The confidence level specified in this standard is: CI.=99% or 95%; the total uncertainty X of its calibration should be calculated according to formula (A1): Xct =± Vx +X2
Where: X,
random uncertainty;
systematic uncertainty.
For random uncertainty with a given confidence level: XCL is calculated according to formula (A2): Xty =
where en.er?,,e.
e +e++..+e
n(n - 1)
is the deviation of a series of single measurements from the arithmetic mean; the number of measurements;
is the t distribution value with a specified confidence level and number of measurements. (A)
(A2)
For systematic errors, they should first be eliminated and corrected, and the residual part is taken as the systematic uncertainty X (CL), and calculated according to formula (A3):
where: K 2.0(CI = 95%) or K = 2. 6(CL.99%) Xes
--the absolute error of calibration sensitivity at the frequency, amplitude and set adapter gain during calibration (see A2). A2 Calculation of absolute error of calibration sensitivity
(A3)
The absolute error of calibration sensitivity at a given calibration frequency, given amplitude and set adapter gain can be calculated by the relative error synthesis formula (A4):
+ekr】
21100/
Ti00arms
Or calculate its speed sensitivity through frequency (f) (see 7.2), and the following coefficient term should be added to formula (A4): (Science)
Recommendation through frequency ( F)2 Calculate its acceleration sensitivity (see 7.2), the following coefficients should be added to formula (A4): ()
Calibration sensitivity of the sensor being calibrated;
Output voltage of the sensor being calibrated;
--- Absolute error of voltmeter reading;
Absolute error of vibration frequency;
Absolute error of frequency ratio counter;
Ratio of laser interference frequency to vibration frequency; - Transverse, rocking and bending vibration of the vibration table, expressed as the absolute value of measurement; ... (A4 )
GB/T 13823.11—1995
The effective value of the sensor vibration output at the calibration frequency; the amplitude caused by hum and noise;
The total distortion, expressed in percentage;
dtot - 100 X
Where: atot—total true effective value output; ttms
The true effective value output at the excitation frequency point.
A3 Calculation of the total absolute error est of the calibration coefficient within the full frequency and full amplitude range The absolute error es of the calibration sensitivity calculated according to A2 is only applicable to the calibration value of the calibration frequency, amplitude and adapter gain that has been determined; and the total uncertainty within the entire frequency and amplitude range should be calculated according to formula A5:)
=± /()() +() ()()
+100)100/
(A5）
Where: S-sensor calibration sensitivity;
e-the absolute error of its calibration sensitivity at the reference frequency, amplitude and set conditioner gain; ItA-the linear deviation of the conditioner frequency, expressed as a percentage relative to the reference calibration coefficient of the conditioner; LF-the linear deviation of the sensor frequency, expressed as a percentage relative to the reference calibration sensitivity of the sensor; LA-the linear deviation of the amplitude of the conditioner, expressed as a percentage relative to the calibration coefficient of the conditioner; La-the linear deviation of the amplitude of the sensor, expressed as a percentage relative to the calibration coefficient of the conditioner. IA—Instability error of the adapter gain and source impedance error, expressed as a percentage of the calibration coefficient of the calibrated adapter; I—Instability of the calibrated sensor, expressed as a percentage of the reference calibration sensitivity; R
—Error caused by changing the gain range of the adapter, expressed as a percentage of the reference calibration coefficient; E—Error caused by the environmental effect of the adapter, expressed as a percentage of the calibration coefficient of the calibrated adapter; Ep
Error caused by the environmental effect of the sensor, expressed as a percentage of the reference calibration sensitivity. Additional notes:
This standard was proposed by the State Administration of Technical Supervision. This standard is under the jurisdiction of the National Technical Committee for Mechanical Vibration and Shock Standardization. This standard was drafted by the China National Institute of Metrology and the China Institute of Testing Technology. The main drafters of this standard are Feng Yuan, Deng Rongxin, Liu Zedong, and Ma Mingde. 590
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