Fasespanning

Fasespanning is a term used in electrical engineering to denote the voltage between a single phase conductor and the neutral conductor in a polyphase distribution system. It is often called phase voltage and is distinct from line-to-line voltage, which is the voltage between two different phases.

In a three-phase system connected in a wye (star) configuration with a neutral, each phase carries a phase voltage relative to neutral, while the line-to-line voltage is related by VLL = √3 × Vphase. This means phase voltage is typically lower than the line-to-line voltage. The exact values depend on regional standards and the presence of a neutral conductor.

Common values include regions with VLL = 400 V and Vphase ≈ 230 V (Europe) and systems with VLL = 480 V and Vphase ≈ 277 V (North America). Some systems, such as delta-connected networks or configurations without a neutral, do not provide a defined phase-to-neutral voltage, which affects which devices can be powered directly from a single phase.

Measurement and usage: Fasespanning is measured between a phase conductor and the neutral (or neutral point). It is used to power single-phase loads and devices rated for phase voltage. Equipment is typically specified by its Vphase rating, and distribution protections are based on phase voltages and currents.

Safety and regulation: Phase voltages can be hazardous, requiring proper insulation, grounding, and protective devices. Clear labeling and adherence to electrical codes are essential in installation and maintenance.

See also: three-phase power, line voltage, neutral, earthing, voltage rating.