Matsayin Karkashin Faduwa

Jinkiri na gaji mai girma na circuit breaker ita ce da ake iya kawo da shi. Don samun cikakken bayanai, ya kamata a duba tushen bayanai da kyakkyawan bayanai da abubuwan nuna don switches da circuit breakers. Kafin yin hanyar gwargwadon circuit breakers, suna bukatar da su yi waɗannan uku masu muhimmanci a cikin maimakon short-circuit:

• Koyar da wani ƙasashen da aka ƙara a cikin system, wanda ake kira breaking capacity na circuit breaker.

• Gwadon ƙarin a kan tsari a lokacin da adadin current ta ƙarewa, wanda ake kira making capacity na circuit breaker.

• Ƙwayar da fault current a matsayin lokaci mai zurfi ne idan wani ƙarin circuit breaker ya ƙoyar da fault, wanda ake kira short-time capacity na circuit breaker.

A cikin tushen bayanai da suka baka, circuit breakers suka buƙata da:

• Yawan poles

• Rated voltage

• Rated current

• Rated frequency

• Operating duty

Bayanai masu tabbataccen game da wannan kalmomi:
Rated Voltage

Rated maximum voltage na circuit breaker shine rike mai girma na RMS (da ya fi nominal voltage) wanda ake kawo da shi, wanda ya zama ƙaramin girman rike da za a yi aiki. Rated voltage tana nufin a kVrms kuma tana amfani da phase-to-phase voltage don circuits na ƙarin.

Rated Current

Rated normal current na circuit breaker shine ƙwarewa ta RMS na current wanda za a iya ƙwayar da shi a matsayin rated frequency da voltage a cikin tushen bayanai masu cutar.

Rated Frequency

Frequency wanda ake kawo da shi don aiki na circuit breaker, wanda standard frequency ta 50 Hz.

Operating Duty

Operating duty na circuit breaker shine yanayin unit operations na musamman a lokutan da ake bayyana. Sequence na aiki tana nufin opening da closing operations na circuit breaker contacts.

Breaking Capacity

Wannan kalmomi tana nufin ƙwarewa mai girma na short-circuit current wanda circuit breaker za iya ƙoyar da shi a cikin tushen bayanai masu transient recovery voltage da power-frequency voltage, tana nufin a kA RMS a lokacin da contact separation. Breaking capacities suna kungiyar da:

• Symmetrical breaking capacity

• Asymmetrical breaking capacity

Making Capacity

Idan circuit breaker ta gwado a cikin maimakon short-circuit, making capacity tana nufin aikinsa da take iya ƙwayar da electromagnetic forces (mai karɓi da square of the peak making current). Making current tana nufin peak value na ƙwarewa mai girma na current wave (da DC component) a kaɗandukan cycle ba a baya da circuit breaker ta gwado tsari.

Short-Circuit Current Withstand Capacity

Wannan tana nufin ƙwarewa ta RMS na current wanda circuit breaker za iya ƙwayar da shi a matsayin lokaci mai zurfi ne a cikin state na fully closed bila da lafiya don lokacin da ake bayyana, tana nufin a kA for 1 second or 4 seconds. Waɗannan ratings suna haɗa da thermal limitations. Low-voltage circuit breakers ba su da waɗannan short-circuit current ratings, saboda haka suna da series overload trips na straight-acting.