Design And Construction Of An Analogue Capacitance Meter
ABSTRACT
There has always been a problem identifying capacitors, due to the enormous variety in size, shape and coding. Most of the time it is impossible to identify them by size due to the different forms of construction. So you have to be able to read and interpret the codes on the body. But if the numbers are missing or microscopic in size, you have a problem. The only solution is to have a piece of test equipment to identify them for you.
A capacitance meter is a piece of electronic test equipment used to measure capacitance, mainly of discrete capacitors. Depending on the sophistication of the meter, it may display the capacitance only, or it may also measure a number of other parameters such as leakage, equivalent series resistance (ESR), and inductance.
This device reads the value of a capacitor and displays it on an analogue meter.
CHAPTER ONE
INTRODUCTION
A capacitance meter is a piece of electronic test equipment used to measure capacitance, mainly of discrete capacitors. Depending on the sophistication of the meter, it may display the capacitance only, or it may also measure a number of other parameters such as leakage, equivalent series resistance (ESR), and inductance. For most purposes and in most cases the capacitor must be disconnected from circuit; ESR can usually be measured in circuit.
Some checks can be made without a specialized instrument, particularly on aluminium electrolytic capacitors which tend to be of high capacitance and to be subject to poor leakage. A multimeter in a resistance range can detect a short-circuited capacitor (very low resistance) or one with very high leakage (high resistance, but lower than it should be; an ideal capacitor has infinite DC resistance). A crude idea of the capacitance can be derived with an analog multimeter in a high resistance range by observing the needle when first connected; current will flow to charge the capacitor and the needle will “kick” from infinite indicated resistance to a relatively low value, and then drift up to infinity. The amplitude of the kick is an indication of capacitance. Interpreting results requires some experience, or comparison with a good capacitor, and depends upon the particular meter and range used.
More sophisticated instruments use other techniques such as inserting the capacitor-under-test into a bridge circuit. By varying the values of the other legs in the bridge (so as to bring the bridge into balance), the value of the unknown capacitor is determined. This method of indirect uses of measuring capacitance ensures greater precision. The bridge usually can also measure series resistance and inductance. Through the use of Kelvin connections and other careful design techniques, these instruments can usually measure capacitors over a range from picofarads to farads. Combined LCR meters that can measure inductance, resistance, and capacitance are available.
Bridge circuits do not themselves measure leakage current, but a DC bias voltage can be applied and the leakage measured directly.
Modern bridge instruments usually include a digital display and, where relevant, some sort of go/no go testing to allow simple automated use in a production environment. As with all modern instruments, bridges can be interfaced to computer and other equipment to export readings and allow external control.
Equivalent series resistance
While not a capacitance meter as such, a dedicated ESR meter will measure the equivalent series resistance (but not the capacitance) of a capacitor without the need to disconnect it from circuit. Capacitors which cause circuit failure due to high ESR with capacity within tolerance, particularly in switch-mode power supplies, are common.
1.2 OBJECTIVE OF THE PROJECT
The objective of this project is construct an electronic testing equipment used to measure capacitance, mainly of discrete capacitors.
1.3 SIGNIFICANCE OF THE PROJECT
There has always been a problem identifying capacitors, due to the enormous variety in size, shape and coding. Most of the time it is impossible to identify them by size due to the different forms of construction. So you have to be able to read and interpret the codes on the body. But if the numbers are missing or microscopic in size, you have a problem. The only solution is to have a piece of test equipment- capacitance meter, to identify them for you.
1.4 SCOPE OF THE PROJECT
This project is capable of measuring all but the largest capacitors used in circuits. As well, the markings of capacitors from salvaged equipment often rub off. By being able to measure these unmarked components, this project will prove useful to the constructor, vintage radio enthusiast or antenna experimenter.
1.5 PURPOSE OF THE PROJECT
The purpose of this work is to design a piece of electronic test equipment used to measure capacitance, mainly of discrete capacitors. Depending on the sophistication of the meter, it displays the capacitance of capacitors only
1.6 PROBLEM OF THE PROJECT
- Results might not be accurate.
- For accurate results, it is suggested to go for DMMs which can measure capacitance.
1.7 APPLICATIONS OF THE PROJECT
- Capacitance Meter can be used to measure capacitance of unknown capacitors.
- Using Arduino for Capacitance Meter makes it easy to implement the project and with slight modifications, the circuit can be made for a wide range of capacitors.
1.7 PROJECT WORK ORGANIZATION
The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:
Chapter one of this work is on the introduction to the study. In this chapter, the background, significance, objective, purpose, scope, application, limitation and problem of the study were discussed.
Chapter two is on literature review of this study. In this chapter, all the literature pertaining to this work was reviewed.
Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.
Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.
Chapter five is on conclusion, recommendation and references.
The Title Page should be the first section of your project “Design And Construction Of An Analogue Capacitance Meter”, providing essential details like the project title, your name, your supervisor’s name, the institution, and the submission date. After that, the Abstract offers a brief summary of your project, touching on its purpose, methods, results, and conclusions in 150-300 words. The Acknowledgments section is where you can thank those who supported your research, such as your supervisor, peers, or organizations that provided resources.
Next, the Table of Contents organizes the Design And Construction Of An Analogue Capacitance Meter by listing its chapters and sections, along with page numbers for easy reference. The List of Figures and List of Tables help guide readers to specific visual elements like graphs, charts, or tables included in the document. There should also be an Abbreviations and Glossary section to explain any specialized terms or acronyms, making the content clearer to readers unfamiliar with the technical language.
The main body of the Design And Construction Of An Analogue Capacitance Meter should start with the Introduction, which provides background information, outlines the research problem, states your objectives, and gives a brief overview of your research methods. Following that, the Literature Review offers an in-depth look at previous research relevant to your project, identifying gaps your study aims to address. The Methodology section then explains the research design, tools, and data collection methods you used to conduct the project and analyze the data.
In the Results and Discussion section, you present your findings and discuss them in relation to the Design And Construction Of An Analogue Capacitance Meter research questions or objectives, often using tables or charts to help explain the data. The Conclusion summarizes the key results, discusses their implications, and suggests possible directions for future research. You may also include recommendations based on your findings, offering practical advice for improvements or applications. Finally, the Design And Construction Of An Analogue Capacitance Meter project should include a References or Bibliography section to list all the sources you cited, as well as Appendices for any additional material. A Statement of Originality is often included to confirm the authenticity of your work