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1 кратно-частотная вибрация
кратно-частотная вибрация
Вибрация с частотой, кратной частоте вращения и не зависящей от неуравновешенности ротора.
Примечание
Такая вибрация может быть вызвана различными причинами, например анизотропией ротора.
[ ГОСТ 19534-74]Тематики
EN
DE
FR
Русско-французский словарь нормативно-технической терминологии > кратно-частотная вибрация
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2 Кратно - частотная вибрация
94. Кратно - частотная вибрация
D. Vibration m it Vielfach-Frequenz
E. Multiple-frequency vibration
F. Vibration sur une multiple frequence de la rotation
Вибрация с частотой, кратной частоте вращения и не зависящей от неуравновешенности ротора.
Примечание. Такая вибрация может быть вызвана различными причинами, например анизотропией ротора
Источник: ГОСТ 19534-74: Балансировка вращающихся тел. Термины оригинал документа
Русско-французский словарь нормативно-технической терминологии > Кратно - частотная вибрация
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3 интергармоническая частота
интергармоническая частота
Любая частота, не кратная основной частоте.По аналогии с порядком кратности гармоник порядок интергармонической частоты основан на отношении к основной частоте. Если это отношение меньше единицы, то такую гармоническую частоту называют субгармонической. В соответствии с рекомендацией МЭК порядок интергармонических частот обозначается буквой «m»
EN
interharmonic frequency
frequency which is a non-integer multiple of the reference fundamental frequency
NOTE 1 By extension of the harmonic order, the interharmonic order is the ratio of interharmonic frequency to the reference fundamental frequency, this ratio is not an integer (recommended notation " m ").
NOTE 2 In the case where " m 1" the term of sub-harmonic frequency may also be used (see IEV 551-20-10).
[IEC 60146-1-1, ed. 4.0 (2009-06)]FR
fréquence interharmonique
fréquence qui est un multiple non entier de la fréquence fondamentale de référence
NOTE 1 Par extension du rang harmonique, le rang interharmonique désigne le rapport de la fréquence interharmonique à la fréquence fondamentale de référence. Ce rapport n’est pas un entier (notation recommandée « m »).
NOTE 2 Lorsque « m < 1 », le terme de fréquence sous-harmonique peut également être employé (voir VEI 551-20-10).
[IEC 60146-1-1, ed. 4.0 (2009-06)]Тематики
EN
FR
Русско-французский словарь нормативно-технической терминологии > интергармоническая частота
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4 частота гармоники
частота гармоники
Частота, кратная основной частоте.
Примечание. Отношение частоты гармоники к основной частоте называют "порядком гармоники".
[ ГОСТ Р 51317.4.30-2008 (МЭК 61000-4-30:2008)]EN
harmonic frequency
frequency which is an integer multiple of the fundamental frequency
NOTE The ratio of the harmonic frequency to the fundamental frequency is the harmonic order (notation: h).
[IEC 61000-4-30, ed. 2.0 (2008-10)]FR
fréquence harmonique
fréquence qui est un multiple entier de la fréquence fondamentale
NOTE Le rapport entre la fréquence harmonique et la fréquence fondamentale est le rang harmonique (notation: h).
[IEC 61000-4-30, ed. 2.0 (2008-10)]Тематики
EN
FR
Русско-французский словарь нормативно-технической терминологии > частота гармоники
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5 частота интергармоники
частота интергармоники
Частота, которая не является целым кратным основной частоте.
Примечания.
1. Аналогично понятию "порядок гармоники" под " порядком интергармоники" понимают отношение частоты интергармоники к основной частоте. Это отношение не выражается целым числом (рекомендуемое условное обозначение m).
2. Если m < 1, допускается применение термина "субгармоническая частота".
[ ГОСТ Р 51317.4.30-2008 (МЭК 61000-4-30:2008)]EN
interharmonic frequency
any frequency which is not an integer multiple of the fundamental frequency
[IEC 61000-4-30, ed. 2.0 (2008-10)]FR
fréquence interharmonique
toute fréquence qui n’est pas un multiple entier de la fréquence fondamentale
[IEC 61000-4-30, ed. 2.0 (2008-10)]Тематики
EN
FR
Русско-французский словарь нормативно-технической терминологии > частота интергармоники
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6 многоцепная линия электропередачи
многоцепная линия электропередачи
Линия электропередачи, имеющая более двух комплектов фазных или разнополярных электрических проводов.
[ ГОСТ 24291-90]EN
multiple circuit line
a line comprising several circuits not necessarily at the same voltage and frequency installed on the same support
[IEV number 466-01-10]FR
ligne multiple
ligne comprenant plusieurs circuits, éventuellement de tensions et de fréquences différents, installés sur le même support
[IEV number 466-01-10]Тематики
EN
DE
FR
Русско-французский словарь нормативно-технической терминологии > многоцепная линия электропередачи
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7 длительный допустимый ток
- courant permanent admissible, m
- courant admissible, m
(длительный) допустимый ток
Максимальное значение электрического тока, который может протекать длительно по проводнику, устройству или аппарату при определенных условиях без превышения определенного значения их температуры в установившемся режиме
[ ГОСТ Р МЭК 60050-826-2009]
Этот ток обозначают IZ
[ ГОСТ Р 50571. 1-2009 ( МЭК 60364-1: 2005)]EN
(continuous) current-carrying capacity
ampacity (US)
maximum value of electric current which can be carried continuously by a conductor, a device or an apparatus, under specified conditions without its steady-state temperature exceeding a specified value
[IEV number 826-11-13]
ampacity
The current in amperes that a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
[National Electrical Cod]FR
courant (permanent) admissible, m
valeur maximale du courant électrique qui peut parcourir en permanence, un conducteur, un dispositif ou un appareil, sans que sa température de régime permanent, dans des conditions données, soit supérieure à la valeur spécifiée
[IEV number 826-11-13]Ampacity, the term is defined as the maximum amount of current a cable can carry before sustaining immediate or progressive deterioration. Also described as current rating or current-carrying capacity, is the RMS electric current which a device can continuously carry while remaining within its temperature rating. The ampacity of a cable depends on:
- its insulation temperature rating;
- conductor electrical properties for current;
- frequency, in the case of alternating currents;
- ability to dissipate heat, which depends on cable geometry and its surroundings;
- ambient temperature.
Electric wires have some resistance, and electric current flowing through them causes voltage drop and power dissipation, which heats the cable. Copper or aluminum can conduct a large amount of current before melting, but long before the conductors melt, their insulation would be damaged by the heat.
The ampacity for a power cable is thus based on physical and electrical properties of the material & construction of the conductor and of its insulation, ambient temperature, and environmental conditions adjacent to the cable. Having a large overall surface area may dissipate heat well if the environment can absorb the heat.
In a long run of cable, different conditions govern, and installation regulations normally specify that the most severe condition along the run governs the cable's rating. Cables run in wet or oily locations may carry a lower temperature rating than in a dry installation. Derating is necessary for multiple circuits in close proximity. When multiple cables are near, each contributes heat to the others and diminishes the amount of cooling air that can flow past the individual cables. The overall ampacity of the insulated conductors in a bundle of more than 3 must be derated, whether in a raceway or cable. Usually the de-rating factor is tabulated in a nation's wiring regulations.
Depending on the type of insulating material, common maximum allowable temperatures at the surface of the conductor are 60, 75 and 90 degrees Celsius, often with an ambient air temperature of 30°C. In the U.S., 105°C is allowed with ambient of 40°C, for larger power cables, especially those operating at more than 2 kV. Likewise, specific insulations are rated 150, 200 or 250°C.
The allowed current in cables generally needs to be decreased (derated) when the cable is covered with fireproofing material.
For example, the United States National Electric Code, Table 310-16, specifies that up to three 8 AWG copper wires having a common insulating material (THWN) in a raceway, cable, or direct burial has an ampacity of 50 A when the ambient air is 30°C, the conductor surface temperature allowed to be 75°C. A single insulated conductor in air has 70 A rating.
Ampacity rating is normally for continuous current, and short periods of overcurrent occur without harm in most cabling systems. The acceptable magnitude and duration of overcurrent is a more complex topic than ampacity.
When designing an electrical system, one will normally need to know the current rating for the following:- Wires
- Printed Circuit Board traces, where included
- Fuses
- Circuit breakers
- All or nearly all components used
Some devices are limited by power rating, and when this power rating occurs below their current limit, it is not necessary to know the current limit to design a system. A common example of this is lightbulb holders.
[http://en.wikipedia.org/wiki/Ampacity]
Тематики
- электротехника, основные понятия
Синонимы
EN
DE
- Dauerstrombelastbarkeit, f
- Strombelastbarkeit, f
FR
- courant admissible, m
- courant permanent admissible, m
Русско-французский словарь нормативно-технической терминологии > длительный допустимый ток
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