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Blueprint Reading
Published in Frank R. Spellman, The Science of Wind Power, 2022
A circuit breaker is an electric device (similar to a switch) that, like a fuse, interrupts an electric current in a circuit when the current becomes too high. The advantage of a circuit breaker is that it can be reset after it has been tripped; a fuse must be replaced after it has been used once. When a current supplies enough energy to operate a trigger device in a breaker, a pair of contacts conducting the current are separated by preloaded springs or some similar mechanism. Generally, a circuit breaker registers the current either by the current's heating effect or by the magnetism it creates in passing through a small coil. Figure 6.84 shows some of the basic symbols that are used to designate circuit breakers on schematic diagrams.
Power Distribution Fundamentals
Published in Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo, Electrical Power Systems Technology, 2021
Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo
The resistance of a conductor expresses the amount of opposition it will offer to the flow of electrical current. The unit of measurement for resistance is the ohm (Ω). The resistivity (p) of a conductor is the resistance for a specified cross-sectional area and length. This measurement is given in circular mil-feet (cmil-ft). The resistivity of a conductor changes with the temperature; so resistivity is usually specified at a temperature of 20°C. The resistivity for some common types of conductors is listed in Table 8-2.
Electrical Power Systems/Improved Efficiency
Published in Dale R. Patrick, Stephen W. Fardo, Ray E. Richardson, Brian W. Fardo, Energy Conservation Guidebook, 2020
Dale R. Patrick, Stephen W. Fardo, Ray E. Richardson, Brian W. Fardo
The resistance of a conductor expresses the amount of opposition it will offer to the flow of electrical current. The unit of measurement for resistance is the ohm (Ω). The resistivity (ρ) of a conductor is the resistance of a given cross-sectional area and length. This measurement is given in circular mil-feet (cmil-ft). The resistivity of a conductor changes with the temperature, so resistivity is usually specified at a given temperature. The resistivities for some common types of conductors are listed in Table 8-l.
Deep learning approaches for fault detection and classifications in the electrical secondary distribution network: Methods comparison and recurrent neural network accuracy comparison
Published in Cogent Engineering, 2020
Daudi Mnyanghwalo, Herald Kundaeli, Ellen Kalinga, Ndyetabura Hamisi
Faults in electric power systems are unpredictable irregular conditions that can be caused by changes in climate conditions, human errors, fire, and electrical hardware failures. Faults in SDN can either be open circuits or short circuits faults. In the distribution networks, short circuits faults occur frequently and can be identified by observing the phase currents (Karić et al., 2017). A short circuit is a type of fault where the electric current passes through an unintended path with very low electrical impedance. Open-circuit faults are the opposite of short circuit faults where there is infinite resistance between two nodes, it is relatively hard to detect open-circuit faults using the current relays (Lau & Ho, 2017). Under ideal states, all phase voltages have the same maximum value but differ in phase from each other at an angle of 120 degrees and deviation of the values by 5% for transmission lines and 10% by distribution lines are considered as the voltage faults.