• Title/Summary/Keyword: Current testing

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Eddy Current Signal Analysis for Transmit-Receive Pancake Coil on ECT Array Probe

  • Lee, Hyang-Beom
    • Journal of the Korean Society for Nondestructive Testing
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    • v.26 no.1
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    • pp.25-29
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    • 2006
  • In this paper, the eddy current signals come from a pair oi transmit-receive (T/R) pancake coil on ECT array Probe are analyzed with the variations of the lift-of and of the distance between transmit and receive coils. To obtain the electromagnetic characteristics of the probes, the governing equation describing the eddy current problems is derived from Maxwell's equation and is solved using three-dimensional finite element method. Eddy current signals from T/R coils on ECT array probe have quite different characteristics compared with ones from impedance coil on rotating pancake coil probe. The results in this paper ran be helpful when the field eddy current signals from ECT array probe are evaluated.

Development of a Multichannel Eddy Current Testing Instrument(II) (다중채널 와전류탐상검사 장치 개발(II))

  • Lee, Hee-Jong;Nam, Min-Woo;Cho, Chan-Hee;Yoo, Hyun-Joo;Kim, In-Chel
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.5
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    • pp.552-559
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    • 2011
  • Recently, the eddy current testing(ECT), alternating current field testing, magnetic flux leakage testing and remote field testing have been used as a nondestructive evaluation method based on the electromagnetic induction phenomenon. The eddy current testing is now widely accepted as a NDE method for the heat exchanger tube in the electric power industry, chemical, shipbuilding, and military. The ECT system mainly consists of the synthesizer module, analog module, analog-to-digital converter, power supplier, and data acquisition and analysis program. In the previous study, the synthesizer module and the analog module which is essential to the ECT system were primarily developed, and in this study the data acquisition and analysis program were developed. The operation system for this program is based on the Windows 7, and optimized for the Korean users, and the specific feature of this program using setup wizard enables inspector to make a setup easily for acquisition and analysis of ECT data. In this paper, the configuration and functions of eddy current data acquisition and analysis program will be introduced.

Effects of Kigong Theraphy in Cocentration of Catecholamines and Cortisol and some Tests on Testing-Stressed (기공외기요법(氣功外氣療法)의 항(抗) 스트레스 효과(效果) 연구(硏究))

  • Kim Ki-Ok
    • Journal of Korean Medical Ki-Gong Academy
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    • v.1 no.1
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    • pp.95-109
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    • 1996
  • To investigate anti-stress effects of Manual Kigong, Manual-Apparatus Combined Kikong, and Systemic Kigong, this experiments were performed changing of plasma catecholaminess and serum cortisol measured. Also using D.I.T.I(Digital Infrared Thermongraphy Imaging), Pulse Analyzer, Electric Current on Neurometer, and Digital Flicker on Testing-Stressed. And following results were abtained. 1) Menual-Appartus Combined Kikong decreased significantly increasing concentration of plasma epinephrine and norepinephrine level in Testing-stressed. 2) Manual Kigong decreased increasing concentration of serum cortisol level in Testing-stressed. 3) Manual Kigong and Manual-Aparatues Combined Kikong increased decreasing thermomerty on the palm's center caused Testing-stressed. 4) All of three treats are small change in SET(Systolic Ejection Time) by Pulse Analyzer caused Testing-stressed. 5) More changes of Electric Current on the Neurometer Diagnosis caused Testing-stressed are as followed. Manual-Apparatus Combined Kikong >Systemic Kigong >Manual Kigong From the results, it may be concluded that Manual-Apparatus Combined Kikong Theraphy having more anti-stress effects than Manual Theraphy. Systemic Kigong Therapy.

A Study on Analysis of Thyristors by the Half-sine wave Voltage (Thyristor의 반파전압에 의한 특성분석에 관한 연구)

  • Park, H.C.;Won, H.J.;Han, S.M.
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.1327-1329
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    • 2000
  • The thyristor among the power-semi-conductor elements, which has large current capacity and high voltage, is used widely nowadays. When the thyristor was being used to the long time, this element may be able to arise the system trip caused by changing the characteristic and dropping the performance. Therefore, it would be necessary to analyze the characteristic of element to maintain the stable operation of the system. In oder to analyze this characteristic, it would be need to test forward direction, reverse direction and leakage current by supplying the half-sine wave voltage. Among these testing, transient current condition is generated from the testing of leakage current. This transient current may be the main factor of the error in the precise measurement of leakage current. Therefore, this paper analyzes the relationship between supply voltage and transient current in measuring leakage current of the SCR, and then suggests the condition and cause of transient current as appearing the leakage current in the testing the leakage current.

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An Analytical Model of Eddy Current Signal using Integral Method (적분법을 이용한 와전류신호의 해석적 모델)

  • Cheong, Y.M.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.11 no.2
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    • pp.7-14
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    • 1991
  • The integral model for the eddy current phenomena has been suggested. The model could lift the limitations of the previously well-known analytical model of eddy current theory. The model could be applied to two-dimentional, arbitary shaped defects. The computer programs have been developed in order to calculate the eddy current signal with the suggested integral method. The eddy current signals by the model calculations have been shown similar patterns to the actual experimental data from the real defects in the calibration standard tubes.

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On the detection of faults on digital logic circuits using current sensor (전류 센서를 이용한 디지탈 논리회로의 고장 검출)

  • 신재흥;임인칠
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.2
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    • pp.173-183
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    • 1996
  • In this paper, a new structure that can do fault detection and location of digial logic circuits more efficiently using current testing techniques is proposed. In the conventional method, observation point for steady state power supply current was only one, but in the proposed method more fault classes are divided for fault detection and location through the ovservation of steady state power supply current at two points. Also, it is shown that this structure can be easily applied in detection of stuck-open fault which is not easy to do testing with conventional current testing techniques. In the presented mehtod, an extra trasnistor is used, and current path is made compulsorily in the CMOS circuits in which no current path can be established in steady state, then it can be known that stuck-open tault is in the MOS transistor on the considering current path, if this path disappears due to stuck-open fault. The validity and the effectiveness is shwon, thorugh the SPICE simulation of circuits with fault and the current path search experiment using current path search program based on transistor short model wirtten in C language on SUN sparc workstation.

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