French term (edited): (V c.a.) 380 V

Das erste "V" steht für das englische "Voltage". Das international genormte Symbol für Spannung lautet "U". Das zweite "V" steht für die Einheit Volt. "a.c." = alternating current, auf Französisch "courant alternatif (c.a.), auf Deutsch "Wechselstrom (WS). Um diese Vielfalt zu vereinheitlichen, wurde von der IEC (International Electrical Commission) ein einheitliches Symbol mit einem Sinuszeichen (~) eingeführt.

Area Electromagnetism / Electromagnetic concepts and quantities
IEV ref 121-11-27
Symbol U
en voltage
(electric) tension
scalar quantity equal to the line integral of the electric field strength E along a specific path linking two points a and b:
[Formel]
where ra and rb are the position vectors for a and b, respectively, and dr is the vector line element

Note 1 – In the case of an irrotational field strength, the voltage is independent of the path and equal to the negative of the electric potential difference between the two points:
[Formel]
Note 2 – The name "voltage", commonly used in the English language, is an exception from the principle that a quantity name should not refer to any name of unit.
de elektrische Spannung, f, Spannung, f
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Area Circuit theory / General
IEV ref 131-11-24
en alternating current
electric current that is a periodic function of time with a zero direct component or, by extension, a negligible direct component
Note – For the qualifier AC, see IEC 60050-151, 151-15-01.
fr courant alternatif, m
courant électrique qui est une fonction périodique du temps à composante continue nulle ou, par extension, à composante continue négligeable
Note – Pour le qualificatif AC, voir la CEI 60050-151, 151-15-01.
de Wechselstrom, m
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Area Electrical and magnetic devices / Behaviour and use
IEV ref 151-15-01
en AC, qualifier
pertaining to alternating electric quantities such as voltage or current, to devices operated with these, or to quantities associated with these devices
Note 1 – The notation "AC" is preferred in English to the notation "a.c." which is an abbreviation of "alternating current" (see IEC 60050-131).
Note 2 – French language uses also the expression "courant alternatif" with an appropriate preposition such as "en", "de", "à" or "pour", or only the adjective "alternatif".
Note 3 – For the marking of electric equipment, either the notation AC (see IEC 61293) or the graphical symbol ~ (see IEC 60417 item 5032) may be used. Example: AC 500 V or ~ 500 V.
Note 4 – According to ISO 31-0 and IEC 60027-1, unit names and unit symbols shall not be qualified by "AC" as an attachment. Example: UAC = 500 V is correct, U = 500 VAC or U = 500 V AC are incorrect.
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