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The reliability design and maintainability design of the micro ammeter were made in the paper. Firstly, reliability and maintainability models for the micro ammeter were established, and corresponding predictions and allocations were made. Secondly, this paper developed an analysis tool to improve the efficiency of reliability calculations greatly. Then, three micro ammeters participated in the 612-hour reliability test, and all successfully passed the reliability assessment.

For painted steel structures, coatings can deteriorate due to factors like ultraviolet radiation, water accumulation, and salt exposure, thereby leading to corrosion. This kind of corrosion tends to originate not only from isolated coating defects but also from multiple adjacent defects. Previous research by the author’s group demonstrated that the presence of adjacent defects can amplify corrosion on steel substrates. However, the precise interaction mechanism between these adjacent defects remains unclear. In this study, circular defects of varying sizes were created on coated steel electrodes to simulate coating defects. The macrocell currents between these defects were measured in an immersion environment using a zero-resistance ammeter (ZRA). The results indicated that when environmental conditions lead to stable anodic and cathodic regions at the defect sites, the anodic corrosion rate increased, while corrosion at the cathodic site was inhibited due to cathodic protection from the anode. Furthermore, when the electrode at a smaller defect became cathodic, the increased protection current density may even prevent any corrosion at that site.

This research aims to measure and analyze the current-voltage (I-V) characteristics of incandescent lamps using a develop practical tool designed to support science process skills (SPS). The tool integrates a DC power supply, digital ammeter, digital voltmeter, incandescent lamp, and connecting wires into a single compact setup. The experiment was conducted by gradually applying voltage from 0,8 V to 3,5 V and recording the resulting current. The data were analyzed through I-V graphs and resistance calculations. the result indicate that the current-voltage relationship appears linear within the tested voltage range, with resistance increasing alongside voltage. This reflects the influence of filament temperature on electrical resistance, although the non-ohmic behavior of the lamp is not significantly evident at low voltages. The linear regression model yielded cofficients of determination (R2) of 0.9943 for the 12V5W lamp and 0.9979 for the 12V10W lamp, indicating excellent model accuracy. These findings confirm that incandescent lamps exhibit temperature-dependent resistance and show that the developed tool is effective for reinforcing electrical concepts in basic physics instruction. Moreover, the practicum engaged science process skills (SPS) such as observation, measurement, classification, and interpretation, with user responses indicating positive perceptions of motivation, conceptual understanding, and active engagement. Thus, the tool not only strengthens conceptual learning but also fosters SPS with clear pedagogical significance.

A potentiostat is an essential piece of analytical equipment for studying electrochemical devices and reactions. As the design of electrochemical devices evolve, applications for systems with multiple working electrodes have become more common. These applications drive a need for low-cost multi-channel potentiostat systems. We have developed a portable, low-cost and scalable system with a modular design that can support 8 to 64 channels at a cost as low as$8 per channel. This design can replace the functionality of commercial potentiostats which cost upwards of $ 10k for certain applications. Each channel in the multi-channel potentiostat has an independent adjustable voltage source with a built-in ammeter and switch, making the device flexible for various configurations. The multi-channel potentiostat is designed for low current applications (nA range), but its purpose can change by varying its shunt resistor value. The system can either function as a standalone device or remotely controlled. We demonstrate the functionality of this system for the control of a 24-channel bioelectronic ion pump for open- and closed- loop control of pH.

The multimeter is a sophisticated electronic measuring device that combines several functions: voltmeter, ammeter and ohmmeter. It measures DC and AC voltage, DC and AC current, resistance, capacitance, frequency, transistor gain, diode checks and wire-check connections. The multimeter also features automatic polarity reversal. Digital multimeters range from 2.5 digits (simple devices) to 3.5 digits (most devices). Slightly more expensive instruments with 4.5, 5 and higher digits are also available. The digit capacity “3.5”, for example, means that the display of the device shows 3 full digits, with a range of 0 to 9, and 1 digit with a limited range, i.e., the device can give readings in the range of 0.000 to 1.999; if the measured value is outside these limits, a changeover to another range is required. Many multimeters now have other functions available. This paper is relevant and can be useful because the multimeter is a lightweight, portable device that is convenient for basic measurements and troubleshooting in hard-to-reach places, as well as being a sophisticated stationary device with many features. Multimeter (from multimeter, tester from test, Avometer from AmperVoltOhmMeter) is a combined electrical measuring device that combines several functions. In the minimum set is a voltmeter, ammeter and ohmmeter. Sometimes a multimeter is performed in the form of current clamps. There are digital and analog multimeters. device multimeter computing technique.

The technological properties of composite materials (thermal, strength, rheology, electrical and morphology) are very important parameters for high-performance applications. In this study, we aimed to improve the properties of PVA by using carbon materials obtained by the pyrolysis of waste tires, with the aim of recycling them instead of disposing of them. For this purpose, PVA biocomposite films containing carbonized waste rubber at different rates were prepared. The thermal properties of the prepared biocomposite films were examined via thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods. While rheological measurements were carried out with a rheometer, bulk conductivities were measured with a pico-ammeter. In addition, the morphology of biocomposite films was determined via field emission scanning electron microscopy. The nanomechanical properties of biocomposite film was investigated via XPM analyses. According to the rheological measurements and nanoindentation hardness results, it is understood that as the amount of carbonized waste rubber increases, flexibility decreases and harder and brittle structures are observed in biocomposite films. The electrical measurement results showed that electrical conductivity increased as the amount of carbonized waste rubber increased. When all the results obtained were evaluated, it could be concluded that biocomposite films obtained by increasing the electrical conductivity and hardness of PVA can be used in the electronics industry.

The article deals with the assessment problems of especially essential structures. Increased demands on prevention of emergency situations and minimizing the consequences in the event of their occurrence require constant determination of especially essential structures condition. Achieving the goal of reliability and continuity of information is possible by coating the structure surface by a layer of electroconductive concrete, working as a monitoring system sensor. The study of the electrical properties of concrete was performed using the voltmeter – ammeter scheme. After the measurements had been made, the conditional electrical resistance of the electrode pair was calculated. The analysis of the above dependencies found that the change in the electrical resistance of the material from its stress approaches the linear law at lower values of W/C over a larger section of the studied interval. Processing of the obtained data showed that the measurement results were significantly affected by the shape and size of the electrodes used during the experiments.

One major change of the future revision of the International System of Units is a new definition of the ampere based on the elementary charge e . Replacing the former definition based on Ampère’s force law will allow one to fully benefit from quantum physics to realize the ampere. However, a quantum realization of the ampere from e , accurate to within 10−8 in relative value and fulfilling traceability needs, is still missing despite the many efforts made for the development of single-electron tunneling devices. Starting again with Ohm’s law, applied here in a quantum circuit combining the quantum Hall resistance and Josephson voltage standards with a superconducting cryogenic amplifier, we report on a practical and universal programmable quantum current generator. We demonstrate that currents generated in the milliampere range are accurately quantized in terms of efJ (fJ is the Josephson frequency) with measurement uncertainty of 10−8 . This new quantum current source, which is able to deliver such accurate currents down to the microampere range, can greatly improve the current measurement traceability, as demonstrated with the calibrations of digital ammeters. In addition, it opens the way to further developments in metrology and in fundamental physics, such as a quantum multimeter or new accurate comparisons to single-electron pumps.

An Internet of Things-based approach to minimizing energy waste and optimizing solar power generation. PV-based energy systems must include energy monitoring for several compelling reasons, such as rising energy prices, expensive operating expenses, and growing demand. The creation of a real-time, Internet of Things-based solar monitoring system is presented in this study. An all-purpose microcontroller with integrated voltage and current sensors was used to gather the information. An IoT analysis platform determines the amount of electricity generated and displays the aggregate data. The real-time current, voltage, and power are measured using an ammeter, voltmeter, and wattmeter. The measurement error between IoT-based and real measurements is studied under different load conditions. For long-term storage, a small flash memory card has been utilized. Thing Speak is an Internet of Things-based analytics software for analysis and visuals. The performance evaluation shows the conformance between the real and IoT-based measurements based on error calculation. The designed system was validated under conditions of constant humidity and temperature. The model can be evaluated in the future for hybrid PV systems with varying humidity and Temperature conditions.

Accurate and reliable characterization of current transformer (CT) performance is essential for maintaining grid stability and power quality in modern electrical networks. CT measurements are key to effective monitoring of harmonic distortions, supporting regulatory compliance and ensuring the safe operation of the grid. This paper addresses a method for the characterization of CTs across an extended frequency range from 50 Hz up to 150 kHz, driven by increasing power quality issues introduced by renewable energy installations and non-linear loads. Traditional CT calibration approaches involve measurement setups that offer ppm-level uncertainty but are complex to operate and limited in practical frequency range. To simplify and expand calibration capabilities, a calibration system employing a sampling ammeter (power analyzer) was developed, enabling the direct measurement of CT secondary currents of an unknown CT and a reference CT without any further auxiliary equipment. The resulting expanded magnitude ratio uncertainties for the wideband CT calibration system are 10 ppm (k=2) up to 10 kHz and less than 120 ppm from 10 kHz to 150 kHz; these uncertainties do not include the uncertainty of the reference CT. Additionally, the operational conditions and setup design choices, such as instrument warm-up duration, grounding methods, measurement shunt selection, and cable type, were evaluated for their impact on measurement uncertainty and repeatability. The results highlight the significance of minimizing parasitic impedances at higher frequencies and maintaining consistent testing conditions. The developed calibration setup provides a robust foundation for future standardization efforts and practical guidance to characterize CT performance in the increasingly important supraharmonic frequency range.