Electrical Engineering Terms V

Variable Frequency Drive A technology where the rotational speed of an electric motor is controlled or varied electronically. Varying Duty. If an electric motor is nameplate-rated with this type of duty cycle, it is rated to operate at loads, and for intervals of time, both of which may be subject …

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Electrical Engineering Terms W

Wire-Wound Rotor (Wound-Rotor Motor or just Wound Rotor). As compared to a squirrel-cage rotor of an electric motor in which aluminum is cast over a steel rotor frame in a mold, the armature circuit of this rotor consists of preformed wraps of insulated wire (windings) similar to the field windings …

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Purpose of Grounding the Utility Power Distribution

fig 1 The static ground wire in the 3-phase electrical utility power transmission-distribution grid

The transfer of electrical power within the electrical-utility power transmission/distribution grid is normally at high voltage (high tension) to reduce the transmission losses (line losses) along the miles of cable that must be installed between the generating plants and the many cities, commercial and industrial sites, and suburban, as well …

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Reversing Three Phase Induction Motors

Reversing Three Phase Induction Motors

Three phase induction Motor rotation can be reversed by changing any two of the three lines feeding power to the motor. It is common standard practice to switch line 1 and line 3. When the motor needs to be run in a clockwise and a counterclockwise rotation, a reverse starter …

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ARCGIS Model Builder Tutorial

Figure 1 Locate the Catalog tab in ArcMap

ArcGIS Introduction This ArcGIS Toolbox provides many tools to manipulate and analyze GIS data. Geoprocessing frequently uses the output of one tool as the input for a second tool which creates a set of tools that are chained together. ArcGIS provides Model Builder, a graphical user interface (GUI) which can …

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