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Equipment and appliances requiring reactive energy

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General rules of electrical installation design
Connection to the MV utility distribution network
Connection to the LV utility distribution network
MV and LV architecture selection guide for buildings
LV Distribution
Protection against electric shocks and electrical fires
Sizing and protection of conductors
LV switchgear: functions and selection
Overvoltage protection
Energy Efficiency in electrical distribution
Power Factor Correction
Power harmonics management
Characteristics of particular sources and loads
PhotoVoltaic (PV) installation
Residential premises and other special locations
ElectroMagnetic Compatibility (EMC)

All AC equipment and appliances that include electromagnetic devices, or depend on magnetically coupled windings, require some degree of reactive current to create magnetic flux.

The most common items in this class are transformers, reactors, motors and discharge lamps with magnetic ballasts (see Fig. L6).

The proportion of reactive power (kvar) with respect to active power (kW) when a piece of equipment is fully loaded varies according to the item concerned being:

  • 65-75% for asynchronous motors (corresponding to a Power Factor 0.8 – 0.85)
  • 5-10% for transformers (corresponding to a Power Factor close to 0.995)

Fig. L6Power consuming items that also require reactive energy