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Hardware for automation
Published in Benny Raphael, Construction and Building Automation, 2023
Electrical currents are created by the movement of charged particles; these charged particles are electrons in commonly used electrical circuits. Electrons move from a point in the circuit to another if there is a potential difference between these points. The potential energy of the electron helps to overcome the energy required to overcome the resistance in the movement. This is similar to an object moving from a higher position to a lower position because there is a difference in the gravitational potential between these two positions. Volt is the unit used to measure the potential difference between two points in a circuit. Ampere is the unit of current, which is the amount of charge that moves through the cross section of the conductor in unit time.
Electrical Aspects
Published in Frank R. Spellman, The Science of Wind Power, 2022
Circuit breakers are protective devices that open automatically at a preset ampere rating to interrupt an overload or short circuit. Unlike fuses, they do not require replacement when they are activated. They are simply reset to restore power after the overload has been cleared.
HVAC Basics
Published in Herbert W. Stanford, Adam F. Spach, Analysis and Design of Heating, Ventilating, and Air-Conditioning Systems, 2019
Herbert W. Stanford, Adam F. Spach
Overcurrent protection is installed to provide automatic means for interrupting (“opening”) a circuit in which the current rises above their rating due to a fault or short circuit. Two types of over-current devices are in common use: circuit breakers and fuses, both rated in amperes.
Effect of Nb Addition on Corrosion Resistance of U-6Zr Alloys
Published in Nuclear Technology, 2023
Masrukan Masrukan, M. Husna Alhasa, Maman Kartaman, Juan Carlos Sihotang
The U-6Zr-xNb alloys (x = 0, 2, 5, 8 wt%) were fabricated by melting depleted U metal, Zr sponge (97.5 wt% purity), and Nb metal (99.80 wt% purity) in an electric arc smelting furnace equipped with a water-cooling system under an electric current of 150 A. The resulting U-6Zr-xNb alloys (x = 0, 2, 5, 8 wt%) were in the form of circular plates with a diameter of 10 mm and a thickness of 5 mm. The samples were prepared for corrosion testing by cutting them into smaller pieces, attaching the sample to copper wire, and mounting with chemical resin. The wire connections were checked using an Ampere, Volt, Ohm-meter (AVO-meter) meter to determine the presence or absence of electric current. The presence of electric current in the sample indicated the sample was ready to be tested with the corrosion test equipment.
Evaluation of the radiological hazard in electron beam welding
Published in Radiation Effects and Defects in Solids, 2021
S. Angelini, G. Cucchi, D. Mostacci
The fluency rate at 1 m, per unit wavelength, can be determined from the following considerations. The emission intensity per unit wavelength per steradian per impinging electron is given by Equation (3). The number of impinging electrons per second is , where is the electron beam current in ampere and e is the electron charge in coulomb. Then the number of photons emitted per unit wavelength, per steradian and per second is given by the product of the two quantities, i.e.. To calculate the fluency at a distance of r m, if r is large compared to the size of the spot irradiated, the latter can be considered a point source, hence the fluence at distance r is given by where r is the distance of interest, in this case 100 cm.
Quantization of magnetoelectric fields
Published in Journal of Modern Optics, 2019
In the problem of interaction of MDM oscillations with a metal surface, the electric displacement current is also neglected. On a metal surface, however, Equation (2) is replaced by the Ampere equation In the MS-wave problems, the current is considered as a surface electric current which just only gives discontinuity of the tangential component of the magnetic field on a metal (62–64). Even so, it is evident, however, that to define the induced electric current in the Ampere equation, the Faraday law should be used. Experimental results of magnetic-induction probing of the fields near a ferrite sample (65,66), show that the Faraday equation yields the electric field associated with the magnetic fields of MDMs. In a view of these experiments, one can conclude that the near-field interaction of MDM resonances with external metal elements cannot be analysed without the Faraday law.