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Long distance HVDC lines carrying hydroelectricity from Canada's Nelson River to this converter station where it is converted to AC for use in southern Manitoba's grid. A high-voltage direct current (HVDC) electric power transmission system uses direct current (DC) for electric power transmission, in contrast with the more common alternating current (AC) transmission systems. [1]
"Sq" current of one daytime vortex within the ionospheric dynamo region: 180 kA Typical current used in electric arc furnace for ferroalloys [11] 10 6: 1 MA High range of Birkeland current: 5 MA Flux tube between Jupiter and Io (moon) [12] 26 MA Sandia National Laboratories, Z machine approximate firing current [13] since 2007 256 MA
Any accelerating electric charge, and therefore any changing electric current, gives rise to an electromagnetic wave that propagates at very high speed outside the surface of the conductor. This speed is usually a significant fraction of the speed of light, as can be deduced from Maxwell's equations , and is therefore many times faster than the ...
Series II current ratings are 20, 30, 60, 100, 200, 300, 350, 500 and 600 amps. The voltage ratings go up to 1000 V AC. These have been replacing the American-style for some time and are much more likely to be found in food processing, data centers, healthcare, entertainment, and other industries.
The front panel typically has LED indicators for "C.V." ("constant voltage") and "C.C." ("constant current"). When the current demanded by the load exceeds the limit set by the user, the power supply automatically switches to the latter mode by regulating the voltage down so much as to prevent the current limit from being exceeded.
Inrush current, input surge current, or switch-on surge is the maximal instantaneous input current drawn by an electrical device when first turned on. Alternating-current electric motors and transformers may draw several times their normal full-load current when first energized, for a few cycles of the input waveform.
In this case, the voltage refers to the voltage across a biological membrane, a membrane potential, and the current is the flow of charged ions through channels in this membrane. The current is determined by the conductances of these channels. In the case of ionic current across biological membranes, currents are measured from inside to outside.
This is why DC series motors were the most common choice for traction purposes until the 1990s, as they can be controlled by voltage, and have an almost ideal torque vs speed characteristic. In the 1990s, high-speed trains began to use lighter, lower-maintenance three-phase AC induction motors.