Перевод: с русского на немецкий

с немецкого на русский

d.c.+resistance+(direct-current)

  • 1 длительный допустимый ток

    1. Strombelastbarkeit, f
    2. Dauerstrombelastbarkeit, f

     

    (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:

    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-немецкий словарь нормативно-технической терминологии > длительный допустимый ток

См. также в других словарях:

  • resistance to direct current — nuolatinės srovės varža statusas T sritis Standartizacija ir metrologija apibrėžtis Elektrinių potencialų skirtumas, padalytas iš srovės stiprio, kai laidininke nėra elektrovaros. atitikmenys: angl. resistance to direct current vok.… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • direct-current resistance — nuolatinės srovės varža statusas T sritis fizika atitikmenys: angl. direct current resistance vok. Gleichstromwiderstand, m rus. сопротивление постоянному току, n pranc. résistance en courant continu, f …   Fizikos terminų žodynas

  • High-voltage direct current — HVDC or high voltage, direct current electric power transmission systems contrast with the more common alternating current systems as a means for the bulk transmission of electrical power. The modern form of HVDC transmission uses technology… …   Wikipedia

  • Current loop — This article is about the electrical signaling schemes. For the oceanic phenomenon, see Loop current. A current loop describes two different electrical signalling schemes. Contents 1 Digital 2 Analog 3 Process control use …   Wikipedia

  • résistance en courant continu — nuolatinės srovės varža statusas T sritis Standartizacija ir metrologija apibrėžtis Elektrinių potencialų skirtumas, padalytas iš srovės stiprio, kai laidininke nėra elektrovaros. atitikmenys: angl. resistance to direct current vok.… …   Penkiakalbis aiškinamasis metrologijos terminų žodynas

  • résistance en courant continu — nuolatinės srovės varža statusas T sritis fizika atitikmenys: angl. direct current resistance vok. Gleichstromwiderstand, m rus. сопротивление постоянному току, n pranc. résistance en courant continu, f …   Fizikos terminų žodynas

  • Direct torque control — (DTC) is one method used in variable frequency drives to control the torque (and thus finally the speed) of three phase AC electric motors. This involves calculating an estimate of the motor s magnetic flux and torque based on the measured… …   Wikipedia

  • Current mirror — A current mirror is a circuit designed to copy a current through one active device by controlling the current in another active device of a circuit, keeping the output current constant regardless of loading. The current being copied can be, and… …   Wikipedia

  • Current divider — Figure 1: Schematic of an electrical circuit illustrating current division. Notation RT. refers to the total resistance of the circuit to the right of resistor RX. In electronics, a current divider is a simple linear circuit that produces an… …   Wikipedia

  • Direct-Shift Gearbox — Transmission types Manual Sequential manual Non synchronous Preselector Automatic Manumatic Semi automatic Electrohydraulic Dual …   Wikipedia

  • Direct negotiations between Israel and the Palestinians (2010-2011) — Benjamin Netanyahu, Mahmoud Abbas, George J. Mitchell and Hillary Clinton at the start of direct talks on September 2, 2010. Direct negotiations between Israel and the Palestinian National Authority have been taking place since September 2010,… …   Wikipedia

Поделиться ссылкой на выделенное

Прямая ссылка:
Нажмите правой клавишей мыши и выберите «Копировать ссылку»