scholarly journals Automatic Measurement System of High Resistance up to100TΩ

2021 ◽  
Vol 2141 (1) ◽  
pp. 012014
Author(s):  
Wen Sun ◽  
Jiajun Peng ◽  
Huan Zhang ◽  
Ying Wang ◽  
Jiaxu Chen
Keyword(s):  
High Resistance ◽  
External Environment ◽  
Automatic Measurement ◽  
Wheatstone Bridge ◽  
Standard Uncertainty ◽  
Dc Voltage ◽  
Automatic Measurement System ◽  
Long Time ◽  
Null Indicator ◽  
Automatic Balancing

Abstract To solve the problems exist in the measurements high resistances in range of 1 MΩ~100 TΩ, such as low precision, poor repeatability, long time consuming and easy to be affected by the external environment, an adapted Wheatstone bridge for high resistances is described. The system uses two DC voltage sources to build a standard proportion, a pico-ammeter as the Null-indicator. The automatic balancing of the bridge is realized through the balance algorithm. The measurement software is compiled to realize the automatic measurement of high resistance. The shielding system is studied, the methods to improve the accuracy are summarized. The experimental results show that the standard uncertainty at 100GΩ reaches 3.2×10−5. The system can meet the calibration requirements of high value resistance, and has been applied in practical work.

Measurement of Piezoelectric Strain Constant Based on Virtual Instrument Technology by Dynamic Method

2013 ◽  
Vol 333-335 ◽  
pp. 2422-2427 ◽  
Author(s):  
Long Biao He ◽  
Rui Wen Zhang ◽  
Hai Jiang Zhu ◽  
Ping Yang
Keyword(s):  
Virtual Instrument ◽  
Piezoelectric Ceramic ◽  
Automatic Measurement ◽  
Resonance Method ◽  
Automatic Measurement System ◽  
Measurement Results ◽  
Piezoelectric Strain ◽  
Good Repeatability ◽  
Instrument Technology ◽  
Dynamic Resonance

Characteristic parameters of piezoelectric ceramic have immeasurable effects on its performance. On the basis of the equivalent circuit of piezoelectric ceramic, dynamic resonance method is used to measure a series of cylindrical piezoelectric coefficients. Based on labview virtual instrument technology, an automatic measurement system with Agilent E4980A impedance analyzer is developed. The characteristics of impedance frequency response are recorded and the admittance circle is drawn. Then the major parameters including d33 are measured automatically and the reports are generated. Finally, E-S(Electric-Strain) method is adopted to verify the reliability of the measurement results. The results showed that the dynamic resonance method had good repeatability with the standard deviation no more than 1.66%, and the test values were in accord with the E-S method.

Table II : Quantitative determination of carbonyl compounds at different odour sources (concentrations in ppb) Rendering plant Gelatine plant neighbourhood neighbourhood Formaldehyde 40 16 Acetaldehyde 39 24 Acetone 36 73 Prcpanal 10 -Isobutyraldehyde 10 30 Pentanal 15 19 Hexanal 3.52 Heptanal 12.5 Octanal 10.5 Nonanal 1 2 acids (figure 7). However extractions always involve a serious decrease in sensitivity, while evaporation of the extract produces a solution in 0.1-0.5 ml of solvent, and only 1 pi of it can be brought in the gas chromatograph. Therefore work is in progress to enhance sensitivity by converting acids in­ to halogenated derivatives, which can be GC-analysed with the more sensitive electron-capture detector. For thiols a similar procedure is investigated as with aldehydes. One possibility is absorption of thiols in an alkaline solution and reaction with 2,4-dinitrochlorobenzene, yielding 2,4-dinitrofenylsulfides, which are analysed by HPLC (9). Sane improvements on removal of reagents at the one hand and on separation of sane by-products on the other hand have to be achieved in order to in­ crease the sensitivity with another factor of ten. 5. CONCLUSION The actual scope and limitations of chemical analysis of odour show that all problems can be tackled as far as emission is concerned. For iititiission measurements seme progress is necessary, but there is no essential reason why chemical analysis would be unable to attain the desired sensitivity for all types of odorants. There is no doubt that in a few years the last dif­ ficulties will be solved. In order to achieve real control of odour nui­ sance, automatic measurement is necessary on a long time basis. There again seme technical development is to be expected. Does this mean that machines are going to decide if an odour is pre­ sent or not? By no means, while the population will always be the reference, and psychophysical measurements will be necessary to make chemical analysis possible.

1986 ◽  
pp. 171-171
Keyword(s):  
Chemical Analysis ◽  
Quantitative Determination ◽  
Alkaline Solution ◽  
Automatic Measurement ◽  
The Other ◽  
Long Time ◽  
Time Basis ◽  
The One ◽  
By Products

Low Frequency Measurements in Amorphous Wire for Studying GMI Effect

2011 ◽  
Vol 495 ◽  
pp. 201-204
Author(s):  
Polykseni Vourna
Keyword(s):  
Magnetic Field ◽  
Low Frequency ◽  
Major Change ◽  
Wheatstone Bridge ◽  
Amorphous Wire ◽  
Dc Voltage ◽  
Gmi Effect ◽  
Offset Voltage ◽  
Ac Current ◽  
The Magnetic Field

When a soft ferromagnetic material is flown by an ac current and a magnetic field is applied at the same time, a major change of its impedance is occurred. The aim of this paper is to investigate the influence of low frequency (1KHz-12KHz) ac current and the applied magnetic field on an amorphous magnetic wire (Co68Fe4.35Si12.5B15) without glass coating. For this purpose an experimental configuration has been setup, based on a Wheatstone bridge which receives an ac input signal from a frequency generator. The output is connected to the amorphous wire wrapped with a coil supplied by a dc voltage for the generation of the magnetic field. The output voltage pulse is measured for two cases a) The value of ac frequency is changing while the value of dc voltage applied to the coil remains constant (the magnetic field remains unchanged) and b) the magnetic field is changing while the ac frequency remains constant to a predefined value. Experimental results of the first scenario showed that when the frequency is altered a non-linear increase of the ac signal is observed at the output which shows an increase of the GMI effect and is related to the non-linearity of the wire’s permeability. For the second scenario the results showed an increase of the output signal offset (voltage) which also indicates an increase of the GMI effect.

HP3 Automatic Measurement System

2014 ◽  
Vol 643 ◽  
pp. 233-236
Author(s):  
Jing Bo Xu ◽  
Jian Song Zhang ◽  
Hong Tao Yu
Keyword(s):  
Control System ◽  
Measurement System ◽  
High Efficiency ◽  
Automatic Measurement ◽  
Application System ◽  
Usb Interface ◽  
Labview Software ◽  
Automatic Measurement System ◽  
Control Relay ◽  
And Control

This paper introduce the thought of USB interface application, an automatic measurement system is as an example. The PC control system of automatic measurement by the Labview software programming, then control relay, and control the work state of the HP3. It shows that the design of USB interface application system is realized by using labview programming easy and high efficiency.

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