International Standard
international standard is a technical standard developed by one or more international standards organization, standards organizations. International standards are available for consideration and use worldwide. The most prominent such organization ...
IEC
The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...
60038, ''IEC standard voltages'', defines a set of standard voltages for use in
low voltage In electrical engineering, low voltage is a relative term, the definition varying by context. Different definitions are used in electric power transmission and distribution, compared with electronics design. electrical safety codes define "low vol ...
and
high voltage
High voltage electricity refers to electrical potential large enough to cause injury or damage. In certain industries, ''high voltage'' refers to voltage above a certain threshold. Equipment and conductors that carry high voltage warrant sp ...
AC and
DC electricity supply systems.
Low voltage
Where two voltages are given below separated by "/", the first is the
root-mean-square
In mathematics and its applications, the root mean square of a set of numbers x_i (abbreviated as RMS, or rms and denoted in formulas as either x_\mathrm or \mathrm_x) is defined as the square root of the mean square (the arithmetic mean of the ...
voltage between a phase and the neutral connector, whereas the second is the corresponding
root-mean-square
In mathematics and its applications, the root mean square of a set of numbers x_i (abbreviated as RMS, or rms and denoted in formulas as either x_\mathrm or \mathrm_x) is defined as the square root of the mean square (the arithmetic mean of the ...
voltage between two phases (exception: the category shown below called "One Phase", where 240 V is the root-mean-square voltage between the two legs of a
split phase
A split-phase or single-phase three-wire system is a type of single-phase electric power distribution. It is the alternating current (AC) equivalent of the original Edison Machine Works three-wire direct-current system. Its primary advantage is t ...
). The three-phase voltages are for use in either four-wire (with neutral) or three-wire (without neutral) systems.
Three-phase 50 Hz
* 230 V / 400 V (formerly 220/380 V)
* 400 V / 690 V (formerly 380/660 V)
* 1000 V phase to phase (3 wire)
Suppliers using 220 V / 380 V or 240 V / 415 V systems were expected by the standard to migrate to the recommended value of 230 V / 400 V by the year 2003. This migration has already been largely completed, at least within the European Union.
Voltage conversion schedule
Three-phase 60 Hz
* 120 V / 208 V
* 240 V
* 230 V / 400 V
* 277 V / 480 V
* 480 V
* 347 V / 600 V
* 600 V / 1000 V
One-phase, three-wire 60 Hz (American split-phase)
* 120 V / 240 V
Table 3 1 kV to 35 kV
Table 3 of IEC 60038 lists nominal voltages above 1 kV and not exceeding 35 kV. There are two series, one from 3 kV up to 35 kV and another one from 4.16 kV up to 34.5 kV.
Table 4 35 kV - 230 kV
Table 4 shows nominal voltages above 35 kV and not exceeding 230 kV.
Table 5 245 - 1,200 kV
Table 5 is systematically different, as the highest voltage for equipment is the characteristic value exceeding 245 kV. The enumeration begins at 300 kV and ends with 1200 kV.
See also
*
Mains electricity by country
References
[googleusercontent.com/siemens.com - Technical information and configuring notes]
2011
External links
Definition of Voltage ranges as per IEC 60038– WIKI - Electrical Installation Guide
*
* https://webstore.iec.ch/preview/info_iec60038%7Bed7.0%7Db.pdf
{{List of IEC standards
Electric power distribution
#60038
Electrical wiring