var

Thân thiện

A technician checks the var reading on the power meter.

Definition

1. Noun:
   • A unit of reactive power in an AC circuit: A "var" is a unit of measurement for reactive power in an alternating current (AC) electrical system. It represents the power that oscillates between the source and the reactive components (like inductors and capacitors) in a circuit, doing no real work.

Usage

• The term "var" is used specifically in electrical engineering and power systems to quantify reactive power.
• It is typically used with numerical values and in technical contexts discussing AC circuit analysis, power factor, and load characteristics.

Examples

• Noun:
  • The capacitor bank supplies 500 var to the system to correct the power factor.
  • Reactive power, measured in vars, is essential for maintaining voltage levels in the transmission grid.

Advanced Usage

• "Volt-ampere reactive (VAR)": This is the full name for the unit, often used interchangeably with "var" in technical documents.
  • The motor's inductive load requires 1.5 kilovolt-amperes reactive (kVAR) of compensation.

Variants and Related Words

• Volt-ampere (VA): A unit of apparent power in an AC circuit, the vector sum of real power (watts) and reactive power (vars).
• Watt (W): A unit of real or active power, which performs actual work.

Synonyms

• Reactive volt-ampere: A synonymous term for the unit.

Notes

• The word "var" is an acronym derived from "volt-ampere reactive." It is always written in lowercase in technical contexts.
• It is a specialized term not commonly used outside of electrical engineering and physics related to power systems.

Học thuật

Noun

1. a unit of electrical power in an AC circuit equal to the power dissipated when 1 volt produces a current of 1 ampere

Từ đồng nghĩa

• volt-ampere