Electrical Measurement Concepts

This set of flashcards covers fundamental concepts and components related to electrical power measurement, specifically addressing DC and AC power, energy meters, and associated terminology.

DC Power

Power calculated based on the direct current circuit, typically given by the formula P = V × I, where P is power, V is voltage, and I is current.

AC Power

Power calculated in alternating current circuits, often represented as P = Vrms × Irms × cos(θ), where θ is the phase angle between the current and voltage.

Three Phase Power Measurement Methods

Methods include the use of wattmeters, direct measurement through multiple circuits, and calculation using line-to-line or line-to-neutral voltages and currents.

Electrodynamometer Wattmeter

A meter designed with features allowing it to accurately measure power in low power factor conditions, typically contains coils and a moving element for operation.

Single Phase Induction Type Energy Meter Parts

Main parts include the driving system, rotating disc, brake system, and registering mechanism.

Causes for Creping in Energy Meters

Creping can occur due to friction, inaccuracies in calibration, or magnetic saturation.

Shading Band

A device used to prevent the false movement of the meter mechanism, typically found in induction meters.

Lag Plate

Used to adjust the phase angle in power measurement devices to ensure accuracy in readings.

Calibration

The process of adjusting and verifying the accuracy of a measurement device against a standard reference.

RSS Meter

A type of meter used to measure RMS (Root Mean Square) values of current or voltage in electrical systems.

Percentage Error Formula

Percentage error of an energy meter is calculated using the formula: (Measured Value - True Value) / True Value × 100%.