Electrical and Electronic Measurements

The efficiency and scour were studied around a breakwater composed of vertical pipes and rock fill under regular waves. Experimental research was done on transmission coefficient (kt), and sour. The variable parameter is increasing in rock fill height (Z) between two rows of piles and increasing in wavelength (L). Three models are studied: Z = 20, 30, and 40 cm, and the rock fill used is a coarse stone with a diameter of 4.5 cm and a porosity of 37%. As the relative rock fill heights grow (Z/h) from 0.5 to 1.0 and with a rising relative wave length (h/L) from 0.12 to 0.36, the transmission coefficient (kt) drops from 0.90 to 0.40. When (Z/h) was varied in the range (0.5-1) at (h/L) equal 0.36, the relative seaward erosion depth reached its maximum at (Dsmax/h) and ranged between 0.03 and 0.1. The increase in the height of rock fill the scour depth upstream. Additionally, for all models, the material harvesting pit was moved downstream.

This paper describes different measuring devices used in electrical system. A measuring instrument is a device in which we can determine the magnitude or value of the quantity to be measured. The electrical quantity such as voltage, current, power, power factor, energy and electronic quantity such as resistance, capacitance, inductance are measured with the help of different measuring devices. These papers introduce different measuring instruments with their working principal.

We developed a variable-output-aperture, laboratory plasma source to enable real-time plasma density control with minimal effect on other plasma properties. The source is capable of producing a low-Earth-orbit-type plasma with electron energies of approximately 0.1-0.7 eV and streaming ion energies of approximately 2-4 eV. The plasma density can be adjusted over two orders of magnitude, thus representing some of the natural variability of the ionosphere. In a given aperture range, the electron and ion density decreased by 73% while the average percent difference in electron and ion density was 0.3% with a standard deviation of 1.4%. The average percent difference in ion energy was 6.3% with a standard deviation of 4.3%. The variable aperture was achieved by a rotating dual-grid system.

The study investigated socioeconomic status, truancy, learning styles, peer pressure and gender as correlates of undergraduate students' academic performance in Taraba State University (TSU), Jalingo, Nigeria. The study adopted correlational research design. The sample of this study was made up 150 undergraduate students of faculty of Education TSU was selected using multistage sampling techniques. The instruments used for data collection were socioeconomic status, truancy, learning styles, peer pressure and gender questionnaire (STLPGQ) and CGPA of undergraduate school in faculty of education, TSU for 2018/2019 session. STLPGQ was validated by three experts in education related disciplines and one expert in measurement and evaluation. STLPGQ was trial tested which yielded the reliability coefficient of 0.89 using Cronbach Alpha. Five research questions raised in the study were answered using multiple regression analysis while the five null hypotheses formulated in the study were tested using ANOVA of regression analysis. The study revealed among other that there is no significant relationship between socioeconomic status and undergraduate students academic performance in TSU, Jalingo [F1, 133 = 6.331; p>0.05]. There is significant relationship between truancy and undergraduate students academic performance [F1, 133 = 18.090; p<0.05]. There is no significant relationship between learning styles and undergraduate students academic performance [F1, 133 = 17.009; p>0.05]. There is significant relationship between peer pressure and undergraduate students academic performance [F1, 133= 19.119; p<0.05]. There is no significant relationship between gender and undergraduate students academic performance [F1, 133 = 10.319; p>0.05]. It was recommended among that, educational administrators and lecturers should set up disciplinary measures to reduce truancy and peer pressure. Parents should help in proper monitoring of undergraduate student activities curb truancy and peer pressure in order to enhance academic performance of students in TSU, Jalingo.

Surja petir yang datang dari saluran transmisi sangat berbahaya bagi peralatan yang ada pada gardu induk, terutama transformator. Transformator adalah komponen utama yang sangat penting dari gardu induk. Akibat terjadi kerusakan di transformator akan mengakibatkan distribusi energi listrik ke konsumen dapat mengalami gangguan. Solusi terhadap masalah ini adalah memasang arrester guna mengatasi tegangan surja petir agar terhindar dari kerusakan transformator pada gardu induk. Untuk mengamankan transformator pada gardu induk 150 kV Bukit Semarang Baru (BSB) dari surja petir dapat dianalisis dengan menggunakan empat kondisi. Metode yang digunakan adalah mengunakan metode diagram tangga. Berdasarkan hasil pengujian yang dilakukan pada trafo daya I 20 MVA, diperoleh hasil transformator dapat terlindungi dari surja petir dengan satu arrester saja. Jika dipasang dua arrester akan lebih baik lagi. Namun apabila tidak dipasang arrester, kondisi tersebut sangat berbahaya karena akan menyebabkan transformator rusak, karena tegangan yang muncul pada transformator yaitu sebesar 939,06 kV, melebihi nilai BIL transformator yaitu 650 kV. Kata kunci: surja petir, transformator, arrester, GI 150/20 kV BSB

A stepped-slope floating breakwater is developed to provide wave protection to small ports and harbours. The width of the structure can be enhanced by increasing the number of breakwater units that are placed side-by-side to each other. This produces three types of test model, i.e. single-row, double-row and triple-row breakwaters. The test models have been tested in monochromatic waves in a wave flume to determine their hydraulic performance in various wave conditions. The incident and reflected wave profiles in the vicinity of the test models are recorded and analysed by using moving-probe method. The hydraulic performance of the test models are quantified by the coefficients of transmission, reflection and energy loss. The experimental results showed that the stepped-slope floating breakwater is an effective antireflection structure and a reasonably good wave attenuator.

The use of submerged breakwaters against coastal erosion problems has some advantages when compared, for example, with the use of similar emerged coastal protection structures and for that reason their use in coastal protection is becoming popular all over the world. Their effect in the wave field and especially in the wave-induced velocities has been analysed by several authors though there is still a lack of knowledge on the wave-flow interaction. The aim of this study was to analyse the behaviour of submerged breakwaters and especially the wave induced velocity field, which can have great impact in the stability of the structures and in the sediment circulation. Two-dimensional scaled physical tests were carried out in the Hydraulics Laboratory wave tank of the University of Porto, in order to understand with more accuracy the influence of the permeability and of the submergence of the breakwaters in the wave-structure interaction. For that reason, tests were performed with the same wave conditions (regular waves), with two different models with the same geometry, one with permeable and one with impermeable rough slopes, and with two water depths (leading to two different freeboards of the structure).

In electric vehicles, it is normal to have an electronic set value for 'gas' and for 'brake'. Traditional potentiometers with sliding contacts are not reliable. Magnetoresistive sensors or hall effect sensors need a magnet on the moving part. The proposed sensor just needs iron on the moving part. It uses an oscillator circuit where the absorbed current is an indication of damping, so how close the iron is to the sensor. The component cost is low and the output has a soft gradual change with the displacement.

This paper describes a microprocessor-controlled three-phase digital meter. The wattmeter is based on the sampling method and, on analogue-to-digital conversion; a single A/D converter ten-bit, built into the microprocessor is used. Transformer accuracy is demonstrated by overlaying noise on current and voltage signals and reducing uncertainty with an external resistive voltage divider. The wide range of current of passing voltage signals, in proportion to the input currents, through a programmable gain amplifier. The total counter pigment is not more than 0.1 per cent.

KWH meter digital secara umum digunakan untuk mengukur konsumsi energi aktif yang dipakai oleh pengguna listrik. Seiring perkembangan teknologi maka sistem pendukungnya kian meningkat sehingga fungsi KWH meter menjadi meluas dengan sistem pra bayar ...

This paper reports a novel low-cost fabrication process of a charged cellular microstructured polydimethylsiloxane (PDMS) material referred as piezo-electret or ferro-electret for micro-sensors applications. The dielectric spectra reached on these structures exhibit a high piezoelectric longitudinal coefficient d 33 of 350pC/N. A mechanical characterization method proves the reliability of this material for low-frequencies applications around 100Hz.

Fast convective radial plasma transport in tokamak edge and scrape off layer (SOL) region is one of the important research topics in controlled thermonuclear fusion. It is based on the hypothesis of detachment of high density plasma blobs from the bulk plasma due to turbulence effects. These blobs are extended along the magnetic field lines and having rather small cross section in the perpendicular plane. They propagate to the outer wall due to B plasma polarization and associated drift. Hence studying the characteristics of these blobs and their motion is very important in understanding and control the fast convective radial transport in tokamaks. To simulate the plasma blob motion in a tokamak edge/SOL like situation we need a plasma chamber with electromagnet. These studies will address burning issue of particle transport as blobs in tokamak edge as well as in SOL. In this paper we report the set up of an electromagnet for the Compact Plasma System (CPS) machine at Ravenshaw Univ...

Engineering in university comprises of a lot of work in the laboratory which is the time where students get the hands-on experience of the theories that have been taught during lectures. Laboratory work makes comprehension of theoretical ideas easier when students can experiment physically with the topics that have been lectured. With certain topics such as Kirchhoff’s law that include voltages and currents, it may be very hard to visualize and understand its principles without a laboratory experiment or assignment. Also, in signals and communication classes that involve a lot of testing with square waves, triangular waves and especially sinusoidal waves, it is useful to have a device that can produce such functions. To address this, a USB powered device that can act as a signal generator, oscilloscope, power supply and logic analyzer now exists.

Working with electronics entails a significant amount of testing and evaluation with signals. Test bench tools including oscilloscopes, function generators and power supplies are often used during experiments. The downside of testbench equipment such as oscilloscopes, power supplies among others is that, they are typically sold as separate, pricey modules. Testbenches used in most laboratories in schools occupy space and usually have to be connected to the mains. Students have to take turns in using this equipment. To address this issue, USB-based devices including the Analog Discovery are available. However, they are also expensive for basic undergraduate courses. This project seeks to develop a cheap USB-powered gadget that can function as a signal generator, oscilloscope and power supply. These were built based on the ARM Cortex M0+ microcontroller along with additional custom circuitry. Power supply output can be controlled between 5V and 12V. Sinusoidal, square and sawtooth waves can also be generated at different frequencies. vi

Electric power and power factor are two parameters that must be considered because they involve the quality of the energy consumed. In order to be able to analyze these, a microcontroller-based power and power factor meter are needed which can be further developed. In this research, a power and power factor meter based on the ATmega328P microcontroller was developed on the Arduino board. Several algorithms are used to calculate the frequency of the grids, as well as the true-RMS of voltage and current. The simulation results show that this system can measure the power and power factor for input voltages of 100 to 300 volts with a frequency of 45 to 156 Hz for loads up to 5 amperes. The mean calculation average error for linear load is 0.28% for active power and -0.33% for apparent power. Meanwhile, for nonlinear loads, the calculation average error for active power is 1.86% and apparent power is 0.47%.

The analog AC-voltmeter usually can only measure the ideal-sinusoid voltage with narrow frequency range. Meanwhile, in fact the grid voltage is often not in the form of an ideal sinusoidal.  To be able to measure a non-sinusoidal AC voltage with a wide range of frequency, a true-RMS voltmeter is needed. The research designed a true RMS measuring system using an ATmega 328P microcontroller. The input voltage is converted to pulse using Schmit triger and fed to the microcontroller’s external interrupt pin to calculate the input signal frequency. Meanwhile the microcontroller’s ADC sampled the input signal with a frequency of 128 times the signal’s frequency. RMS voltage calculations are performed using arithmetic operations for 16 and 32 bit integer variables. The test results show that the system can measure voltages with zero errors from 100 to 275 volts with a frequency of 50 Hz. The system can also measure voltages with zero errors at 220 volt with frequencies from 40 Hz to 150 Hz...

Cos phi meter adalah alat yang digunakan untuk mengetahui, besarnya faktor daya (power factor) yang merupakan beda fasa antara tegangan dan arus. Dalam pengertian sehari-hari disebut pengukur Cosinus phi (ϕ).Rancang bangun media pemelajaran Cos phi meter dan watt meter berbasis arduino terdiri dari 3 bagian utama yaitu rangkaian Input, rangkaian pemroses dan rangkaian Output. Rangkaian Input terdiri dari rangkaian sensor tegangan, rangkain sensor arus, serta rangkaian pembaca faktor daya. Rangkaian pemroses terdiri dari arduino uno R3. Rangkaian output terdiri dari rangkaian penampil berupa LCD 16 x 2. Bagian software dirancang menggunakan bahasa C dengan mengunakan program arduino. Besarnya presentasi kesalahan ukur faktor daya yaitu sebesar 20,1 % untuk beban resistif, 27,2 % untuk beban kapasitif, dan 72,2 % untuk beban Induktif .

The electrostatic charge accumulation of extremely pure substances usually makes the manufacturing technology more difficult. The electrostatic behaviour of the materials can be examined by the measurement of charge decay time, but the conductivity of pure materials is very low, therefore they show very long charge decaying times. Hence, this quantity is not applicable for reliable electrostatic characterisation of pure powders. In this investigation, dielectric and charge accumulation measurements were executed on extremely pure powders. The results of leakage current and voltage response methods show significant difference between the powders according to their electrostatic behaviour. The result of dielectric measurements is confirmed by the charge accumulation measurement. The findings reveal the importance of the investigation of slow polarisation mechanisms in the charge accumulation processes of powders.

A digital sampling algorithm that uses a two high resolution integrating Voltmeters which are synchronized by Phase Lock Loop (PLL) time clock for accurately measuring the parameters, active and reactive power, for sinusoidal power measurements is presented. The PLL technique provides high precision measurements, root mean square (rms), phase and complex voltage ratio, of the AC signal. The system has been designed to be used at the Korean Research Institute of Standards and Science (KRISS) as a reference power standard for electrical power calibrations. The test results have shown that the accuracy of the measurements is better than 10 μW/VA and the level of uncertainty is valid for the power factor range zero to 1 for both lead and lag conditions. The system is fully automated and allows power measurements and calibration of high precision wattmeters and power calibrators at the main power frequencies 50 and 60 Hz.

For the monitoring of deeper layers of human tissue temperature during cooling the four-thermistor transducer was proposed. The Steinhart-Hart equation was used to linearize the temperature-resistance characteristics of thermistors. Transducer structure and temperature fields in the tissues of the body were simulated using COMSOL Multiphysics. The ratio of transducer's equivalent thermal resistances was determined using numerical and physical experiments. The difference of values of the temperature measured at a depth of 30 mm in tissue by invasive and non-invasive method was less than ± 0.5°C.

Area=A Either A, d or ε can be varied. INDUCTIVE TRANSDUCER: • In inductive transduction, the measurand is converted into a change in the self inductance of a single coil. It is achieved by displacing the core of the coil that is attached to a mechanical sensing element CLASSIFICATION OF TRANSDUCERS According to Transduction Principle CLASSIFICATION OF TRANSDUCERS According to Transduction Principle PIEZO ELECTRIC INDUCTION : • In piezoelectric induction the measurand is converted into a change in electrostatic charge q or voltage V generated by crystals when mechanically it is stressed as shown in fig. PHOTOVOLTAIC TRANSDUCTION : • In photovoltaic transduction the measurand is converted to voltage generated when the junction between dissimilar material is illuminated as shown in fig.

Sebuah prototipe sistem pengukur daya berbasis Arduino Uno diusulkan untuk mengukur dan menampilkan daya semu (apparent powerS) peralatan listrik. Prototipe sistem yang diusulkan direalisasikan menggunakan 4 sub-sistem: (1) sensor VMAX menggunakan rangkaian full-wave rectifier dengan beban fixed-resistor yang dihubungkan ke Arduino; (2) sensor IRMS menggunakan 5A noninvansive AC current sensor module yang dihubungkan ke Arduino; (3) modul LCD 20x4 character dengan koneksi I 2 C; dan (4) Arduino Uno board. Arduino digunakan untuk membaca VMAX (keluaran full-wave rectifier), VRMS (keluaran 5A non-invansive AC current sensor module) selama 20mS dan kemudian dikonversikan menjadi VRMS dan IRMS dan kemudian nilai daya semu dihitung menggunakan persamaan S = IRMS×VRMS. Nilai VRMS, IRMS, dan S ditampilkan ke LCD. Prototipe sistem pengukur daya peralatan listrik telah selesai dibuat, diuji, dan dibandingkan dengan menggunakan multifunctional mini ammeter WanF® DO2A dapat mengukur daya semu peralatan listrik rumah-tangga dengan rentang dari 61 Watts sampai dengan 380 Watts dengan nilai % kesalahan pengukuran sebesar ± 10 %.

His current areas of interest include PC/DSP based instruments, motion and industrial process control, insulation-condition assessment techniques and advanced signal-processing applications. Dr Purkait has published extensively in international journals and conference proceedings on various topics related to his research paradigm.

A-2 CONTRIBUTOR LIST 405 A-3 DESIGN SCIENCE LICENSE 409 INDEX 412 price. The electronic signal generated by the keyboard is conducted to your circuit via a headphone cable plugged into the "headphones" jack. More details regarding the use of a "Musical Keyboard as a Signal Generator" may be found in the experiment of that name in chapter 4 (AC). 1.2.3 Supplies Wire used in solderless breadboards must be 22-gauge, solid copper. Spools of this wire are available from electronic supply stores and some hardware stores, in different insulation colors. Insulation color has no bearing on the wire's performance, but different colors are sometimes useful for "color-coding" wire functions in a complex circuit. Spool of 22-gauge, solid copper wire Note how the last 1/4 inch or so of the copper wire protruding from the spool has been "stripped" of its plastic insulation. ====================================== An alternative to solderless breadboard circuit construction is wire-wrap, where 30-gauge (very thin!) solid copper wire is tightly wrapped around the terminals of components inserted through the holes of a fiberglass board. No soldering is required, and the connections made are at least as durable as soldered connections, perhaps more. Wire-wrapping requires a spool of this very thin wire, and a special wrapping tool, the simplest kind resembling a small screwdriver. Wire-wrap wire and wrapping tool 1.3 Contributors Contributors to this chapter are listed in chronological order of their contributions, from most recent to first. See Appendix 2 (Contributor List) for dates and contact information. Michael Warner (April 9, 2002): Suggestions for a section describing home laboratory setup. Chapter 2 BASIC CONCEPTS AND TEST EQUIPMENT Contents 2.1 Voltmeter usage. .

Frekuensi merupakan jumlah gelombang dalam satu detik. Frekuensi listrik adalah banyaknya gelombang listrik yang terdapat dalam satu detik. Frekuensi listrik merupakan salah satu parameter gelombang listrik yang dapat mempengaruhi kinerja dari sistem tenaga listrik. Perubahan nilai frekuensi listrik bagi sebagian perangkat dapat berpengaruh besar. Salah satu akibat dari frekuensi listrik yang tidak stabil adalah mengakibatkan perputaran motor listrik sebagai penggerak mesin-mesin produksi pada industri manufaktur menjadi tidak stabil, dimana hal ini akan mengganggu proses produksi. Frekuensi listrik di Indonesia berada pada kisaran 50Hz, perubahan pada besar nilai frekuensi masih dapat ditolerir apabila masih berada dalam batas. Karena itu penting untuk mengembangkan suatu alat untuk memantau besar nilai frekuensi listrik secara real-time. Frekuensi meter listrik yang dibuat untuk mengukur dan memantau besar frekuensi listrik. Alat yang dibuat untuk penelitian kali ini merupakan sua...

The permanent magnet moving coil instrument or PMMC type instrument uses two permanent magnets in order to create stationary magnetic field. These types of instruments are only used for measuring the dc quantities as if we apply ac current to these type of instruments the direction of current will be reversed during negative half cycle and hence the direction of torque will also be reversed which gives average value of torque zero. The pointer will not deflect due to high frequency from its mean position showing zero reading. However it can measure the direct current very accurately.

Frekuensi merupakan jumlah gelombang dalam satu detik. Frekuensi listrik adalah banyaknya gelombang listrik yang terdapat dalam satu detik. Frekuensi listrik merupakan salah satu parameter gelombang listrik yang dapat mempengaruhi kinerja dari sistem tenaga listrik. Perubahan nilai frekuensi listrik bagi sebagian perangkat dapat berpengaruh besar. Salah satu akibat dari frekuensi listrik yang tidak stabil adalah mengakibatkan perputaran motor listrik sebagai penggerak mesin-mesin produksi pada industri manufaktur menjadi tidak stabil, dimana hal ini akan mengganggu proses produksi. Frekuensi listrik di Indonesia berada pada kisaran 50Hz, perubahan pada besar nilai frekuensi masih dapat ditolerir apabila masih berada dalam batas. Karena itu penting untuk mengembangkan suatu alat untuk memantau besar nilai frekuensi listrik secara real-time. Frekuensi meter listrik yang dibuat untuk mengukur dan memantau besar frekuensi listrik. Alat yang dibuat untuk penelitian kali ini merupakan sua...

Some new schemes using active circuits are proposed for realization of sinusoidal flux in a ferromagnetic core during loss testing. One of the suggested configurations facilitates the loss measurements to be made from the primary side itself. A few filter circuits enable the tests to be carried out on normal supply mains without the need for a calibration generator. Experimental results are reported to confirm the acceptability of the proposed schemes.

A circuit employing a voltage follower is given for obtaining a sinusoidal flux in a ferromagnetic core. The amplifier just supplies the copper loss of the exciting winding. [4] G. W. Swift, "Realization of sinusoidal flux in a transformer iron sample,"

Though conventional potentiometric type resistive transducers are simple to construct and use, they are not popular owing only to the fact that a sliding contact needs to be employed. In this paper, a potentiometric type resistive displacement transducer that uses a contactless slide is presented. A dedicated signal conditioning circuit proposed here operates on the output of a slide that moves, without having a physical contact, on the resistive element and provides an output voltage directly proportional to the quantity being sensed (displacement or velocity). Since the output of the circuit is dependent only on a dc reference voltage and the measurand, an acceptable level of accuracy can be obtained with ease. Results of simulation studies and experimentation establish the efficacy of the proposed scheme.

The permanent magnet moving coil instrument or PMMC type instrument uses two permanent magnets in order to create stationary magnetic field. These types of instruments are only used for measuring the dc quantities as if we apply ac current to these type of instruments the direction of current will be reversed during negative half cycle and hence the direction of torque will also be reversed which gives average value of torque zero. The pointer will not deflect due to high frequency from its mean position showing zero reading. However it can measure the direct current very accurately.

Intisari ---Transformator arus merupakan peralatan yang digunakan dalam pengukuran besaran arus pada instalasi tenaga listrik di sisi primer dengan mentransformasikan besaran arus tinggi tersebut ke amplitudo yang sesuai bagi peralatan proteksi ataupun pengukuran yang terhubung dengan transformator arus tersebut. Dalam penelitian ini dibuat suatu sistem alat ukur arus yang terdiri dari transformator arus, pengkondisi sinyal, mikrokontroler ATMega32, LCD 2x16 dan komponen pendukung lainnya. Sistem yang telah dibuat kemudian diuji untuk mengukur arus pada beragam beban yaitu resistif, kapasitif, induktif, dan campuran. Hasil pengukuran kemudian dibandingkan dengan hasil pengukuran menggunakan amperemeter analog dan tang ampere. Alat yang dibuat menunjukkan kemampuan pengukuran yang cukup baik, dimana selisih pengukuran dengan amperemeter analog sangat kecil. Rata-rata deviasi pengukuran alat ini dibandingkan dengan amperemeter analog adalah 1.18 %. Arus terkecil yang dapat dideteksi o...

Cos phi meter adalah alat yang digunakan untuk mengetahui, besarnya faktor daya (power factor) yang merupakan beda fasa antara tegangan dan arus. Dalam pengertian sehari-hari disebut pengukur Cosinus phi (ϕ).Rancang bangun media pemelajaran Cos phi meter dan watt meter berbasis arduino terdiri dari 3 bagian utama yaitu rangkaian Input, rangkaian pemroses dan rangkaian Output. Rangkaian Input terdiri dari rangkaian sensor tegangan, rangkain sensor arus, serta rangkaian pembaca faktor daya. Rangkaian pemroses terdiri dari arduino uno R3. Rangkaian output terdiri dari rangkaian penampil berupa LCD 16 x 2. Bagian software dirancang menggunakan bahasa C dengan mengunakan program arduino. Besarnya presentasi kesalahan ukur faktor daya yaitu sebesar 20,1 % untuk beban resistif, 27,2 % untuk beban kapasitif, dan 72,2 % untuk beban Induktif .

Cos phi meter adalah alat yang digunakan untuk mengetahui, besarnya faktor daya (power factor) yang merupakan beda fasa antara tegangan dan arus. Dalam pengertian sehari-hari disebut pengukur Cosinus phi (ϕ).Rancang bangun media pemelajaran Cos phi meter dan watt meter berbasis arduino terdiri dari 3 bagian utama yaitu rangkaian Input, rangkaian pemroses dan rangkaian Output. Rangkaian Input terdiri dari rangkaian sensor tegangan, rangkain sensor arus, serta rangkaian pembaca faktor daya. Rangkaian pemroses terdiri dari arduino uno R3. Rangkaian output terdiri dari rangkaian penampil berupa LCD 16 x 2. Bagian software dirancang menggunakan bahasa C dengan mengunakan program arduino. Besarnya presentasi kesalahan ukur faktor daya yaitu sebesar 20,1 % untuk beban resistif, 27,2 % untuk beban kapasitif, dan 72,2 % untuk beban Induktif .

The paper discussed sources of data. Data is a set of values of qualitative or quantitative variables. Data is facts or figures from which conclusions can be
drawn. Before one can present and interpret information, there has to be a process of gathering and sorting data. Just as trees are the raw material from which paper is produced, so too, can data be viewed as the raw material from
which information is obtained. It is evident from the above discussion that primary data is an original and unique data, which is directly collected by the researcher from a source such as observations, surveys, questionnaires, case
studies and interviews according to his requirement

This paper describes three impedance bridges in operation at INMETRO: the two-and four-terminal-pair coaxial bridges and a digital quadrature bridge, including several comparisons among them in the nanofarad capacitance range. These comparisons have the objective to verify the performance and reliability of the coaxial bridges between themselves and to infer on the capabilities of a digital one, recently put in operation. The results obtained indicate that the more accurate coaxial systems are compatible with one another in the 10 −7 level. The digital bridge is in agreement with the coaxial ones within a few parts in 10 6 or even less in some cases.

Many times in an industry the angle needs to be measured of reference disc or button, which is very vital. In order to measure this angle the proposed changes are made to the existing LVDT and with these changes we can measure the change of angle in degrees on electronic display. The name given to the arrangement is Angular Variable Differential Transformer (AVDT).

Some new schemes using active circuits are proposed for realization of sinusoidal flux in a ferromagnetic core during loss testing. One of the suggested configurations facilitates the loss measurements to be made from the primary side itself. A few filter circuits enable the tests to be carried out on normal supply mains without the need for a calibration generator. Experimental results are reported to confirm the acceptability of the proposed schemes.

A circuit employing a voltage follower is given for obtaining a sinusoidal flux in a ferromagnetic core. The amplifier just supplies the copper loss of the exciting winding. [4] G. W. Swift, "Realization of sinusoidal flux in a transformer iron sample,"

Pile breakwater consists of a number of piles spaced closely. It works similar to the offshore breakwater by attenuating the energy of the waves and it is due the turbulence caused because of wave-pile interaction. The efficiency of the pile breakwater of single row and two rows is investigated numerically. An open source Computational Fluid Dynamics (CFD) software REEF3D is used in the present study. Initially the grid convergence study is conducted in a rectangular wave flume with a two-dimensional setup and the results are evaluated by comparing the numerical wave profile with the theoretical profile in accordance with the adopted wave theory. The efficiency of the numerically modelled pile breakwater is investigated in terms of the transmission coefficient. The simulations carried out are in accordance with the physical model studies as reported by Subba Rao et al., (1999). The numerically obtained results are validated with the experimental data. The numerically obtained result...

The permanent magnet moving coil instrument or PMMC type instrument uses two permanent magnets in order to create stationary magnetic field. These types of instruments are only used for measuring the dc quantities as if we apply ac current to these type of instruments the direction of current will be reversed during negative half cycle and hence the direction of torque will also be reversed which gives average value of torque zero. The pointer will not deflect due to high frequency from its mean position showing zero reading. However it can measure the direct current very accurately.

A new type of coaxial shunt for high frequency ac-dc current transfer standards has been designed. The structure of the shunts with nominal current from 100 mA to 5 A are made of a disk with two coaxial conductive layers in one side. SMD resistors are soldered in parallel between the two layers. Two conductive screens are applied in both side of the disk. In order to reduce stray effects, the structure has ideally no common magnetic interaction between the input current and the output voltage and practically a very low section where the magnetic field is confined, so allowing a flat response in a wide frequency range.

Used in electrical energy distribution effort to the community. Know the factors that affect the capacity of power distribution transformers for 3 phase and 1 phase and to know system maintenance performed on the distribution network and transformer at. PLN (Persero) Branch Pinrang .All data that is required in this study was obtained through several instruments such as surveys or direct observation , interviews , and a review of literature used to complement and meet the required data. All data were collected and analyzed using descriptive analysis. These results prove that the distribution network is used on the PT. PLN (Persero) Branch Pinrang consists of a primary distribution channels , distribution transformers and secondary distribution channels. This distribution network is used to distribute electrical energy to the entire community of Pinrang. Kapasitas of a distribution transformer for 3 phases and the first phase is determined by the amount of load that is served is added to the burden of the future development. System maintenance is performed on the distribution network and transformer at. PLN (Persero) Branch Pinrang done regularly and proactively with emphasis on preventive measures aiming to prevent disturbance of the action reprensif in overcoming the disorder.

The justification of the linear displacement sensors installation in mine workings is described in this paper. The required technical characteristics of the sensors are given. The main types of primary linear displacement converters are presented. The choice of inductive solenoid-type converters and sensors based on linear differential transformers (LVDT) is justified. The advantages and disadvantages of inductive transducers, their accuracy and measurement limits are described, and measuring methods of inductance of the solenoid-type transducers and the converter output signal based on LVDT are considered. The results of sensors experimental studies based on the solenoid-type inductive transducers are presented.

Semakin meningkatnya konsumsi energi listrik membuat pasokan listrik dari PLN terkadang tidak stabil dan terkadang terjadi pemadaman bergilir. Gangguan tegangan yang terjadi ini tidak mudah untuk diprediksi kapan waktunya. Alat ukur yang dapat mendeteksi di pasaran harganya masih relative maha. Oleh karena itu dikembangkan alat pendeteksi gangguan tegangan PLN baik karena adanya beban induktif, kapasitif ataupun resistif yang dapat terdeteksi secara real time dan dapat ter-record di dalam harddisk. Metoda penelitian ini adalah membuat alat pendeteksi tegangan menggunakan Mikrokontroles Arduino uno R3 yang terintregrasi dengan LABVIEW. Recording dilakukan pada titik terakhir sambungan PLN dengan beban dan tanpa tambahan beban. Penelitian menunjukkan bahwa rata-rata nilai tegangan tanpa tambahan beban= 216.74 Volt, beban induktif = 208.38 Volt, beban kapasitif = 211.25 Volt, beban resistif = 210.95 Volt. Dari hasil pengukuran tersebut didapat beban induktif sangat berpengaruh terhadap terjadinya penurunan tegangan. Data yang yang diterima dapat diproses melalui output sesuai dengan perintah yang diinginkan secara continue dan real time. Kata kunci: ARDUINO UNO R3, GANGGUAN TEGANGAN dan LABVIEW.

Pemantauan terhadap parameter keluaran panel surya sangat perlu dilakukan untuk menilai kinerja sebuah panel surya pada kondisi lingkungan yang nyata. Paper ini bertujuan memberikan suatu teknik baru pemantauan secara langsung dan real time terhadap parameter keluaran dari sebuah panel surya yaitu tegangan dan arus pada kondisi lingkungan tertentu. Untuk memenuhi keperluan pemantauan tersebut, sistem pemantauan kinerja panel surya yang dirancang dilengkapi dengan sensor pengukur arus dan tegangan yang telah dikalibrasi, sistem akuisisi data yang diintegrasikan ke spreadsheet Excel menggunakan program aplikasi PLX-DAQ dan kartu memori sebagai penyimpan data cadangan. Perancangan sistem berbasis mikrokontroler Arduino Atmega 328P dan dihubungkan ke komputer melalui port serial RS232. Kelebihan dari sistem pemantauan ini adalah hasil pengukuran dari setiap sensor dapat diproses secara langsung dan ditampilkan dalam bentuk grafik pada kondisi real time. Informasi mengenai tegangan dan arus dari panel surya yang dikumpulkan pada kondisi real time dapat diperoleh langsung melalui spreadsheet Excel tanpa memerlukan program ulang terhadap Arduino. Fasilitas ini memberikan kemudahan untuk pengolahan data selanjutnya.