making current is a peak value attain at first cycle when the circuit breaker is close.the making current rating is expressed in "peak" value of the maximum ac current it can safely close on that's why it is always have higher value than breaking current. Making current is limited by the withstand capability of the contacts. Breaking current is based on the ability of the contacts to interrupt the current. If the contacts are not able to interrupt the current when they open, the heat energy in the resulting arc will often destroy the device. the breaking current rating is expressed in RMS value of the current.
First thing, there is nothing like vacuum circuit contactor. It is a vacuum contactor. It has hrc fuse for protection against short circuit and have vacuum bottles in which contacts move to get close and open. It will never trip bcas it does not have tripping mechanism, it does not have operating mechanism. It's contacts are made only to make and break normal current. It is used to start and stop a motor only. It does not have ka rating for fault current. Vacuum circuit breaker is a real fault current breaker which trips during a fault like short circuit, earth fault, under or over voltage or any one. It encompasses the operating mechanism to break the contacts at a very high speed and also need a spring charging mechanism to turn the breaker on. It has very highly rated contacts inside a heavy capacity vacuum bottles. It has realese ( something like solenoid ) which pulls the plunger after it get signals from various protection relays in case of fault. It is not meant to operate for day to day start and stop operation of motor. It has ka rating for fault current. Analogus to ordinary home circuit, vcb is like a circuit breaker at home inside a panel and vc is a relay in our any of instruments at home. Analogus to low voltage situation, vcb is like a fault current ( air, or bulk oil or minimum oil ) circut breaker and vc is like an ordinary contactor
Depends on manufacturer..Normally the ratings are as follows 1. Service short circuit breaking capacity is 7.5 kA 2. Rated short circuit breaking capacity is 10 kA.
It has been some time but here goes. The circuit breaker size can be found when some other information is given. For a given voltage value, the size of the cb is basically found using the formula P(Kw) = IV here the value of I is approx the value of the circuit breaker. The solution is not so simple since there are normally tolerances set by the different regulator organisations as to these values. Another situation to consider is the type of current and voltage you are using ie ac or dc, Vac or Vdc. also the amount of phases if it is ac voltages we are considering . If 3 phase ac voltage and current the formula used is as follows P(kva) = 1.73 x IL x VL x pf where pf , the power factor is the introduced and kva the apparent power is used instead of kw here because under most conditions a power factor of 1 cannot be achieved. IL and VL are the line current and voltage. Gladstone
It is a carrier Frequency Band between 26.5GHz and 40GHz
kAIC means the maixum current interruption capacity of circuit braker. IC stands for interruption capcaity. So if a CB has 10 kAIC means it can cut off current of up to 10 kA without damaging itself.
No, not all circuit breakers are designed to interrupt large fault currents. High-interrupting capacity circuit breakers are specifically engineered to handle and interrupt large fault currents safely without causing damage to the electrical system. It is important to match the circuit breaker's interrupting capacity with the potential fault currents in the system to ensure proper protection.
KA stands for kilo-amps, or thousands of amps. Thus a 2KA breaker means it will trip when the load exceeds 2,000 amps.
Pre 1970 (72?) breakers were specified with a MVA assymmetrical interrupting rating. Breakers are now spec'd with a symmetrical rating, which is provided in amps or kA. There is an ANSI standard that provides conversion from assymetrical to symmetrical and vice versa. Converting from Asym. to symmetrical involves analyzing the open close interval, time between successive openings, breaker operating speed, breaker operating voltage, and whether the breaker is connected to a generator bus or not (usually has an unusually high X/R ratio which results in more DC offset). So...it is the interrupting rating, or how much (short circuit) power the breaker can interrupt. The faster the breaker operates, the higher the voltage, the closer it is to a generator, and the more times it is expected to open results in a lower interrupting amperage capability. If it is used beyond this rating, it is likely to internally fault when attempting to open.
Ics: Service breaking capacity for a short circuit (in kA)Icu: Ultimate breaking capacity (in kA)Icw: Withstand capacity (usually in kA for 1 sec)
In the terms of voltage it should be in kV but when we are using the current term than it should be in kiloamperes or kA because the short circuit current level of the circuit breaker is very high.AnswerIt depends entirely on the voltage level and load currents you are talking about. It will be completely different for, say, a 132-kV system than for, say, a 230 V system. So, does your question apply to high-voltage systems or low-voltage systems?
making current is a peak value attain at first cycle when the circuit breaker is close.the making current rating is expressed in "peak" value of the maximum ac current it can safely close on that's why it is always have higher value than breaking current. Making current is limited by the withstand capability of the contacts. Breaking current is based on the ability of the contacts to interrupt the current. If the contacts are not able to interrupt the current when they open, the heat energy in the resulting arc will often destroy the device. the breaking current rating is expressed in RMS value of the current.
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A common household circuit consists of a breaker, wiring, outlets, and switches. The breaker protects the circuit from overloading, the wiring carries the electricity to the outlets and switches, and the outlets provide the connection for devices to receive power. The switches control the flow of electricity to the outlets or lights.
First thing, there is nothing like vacuum circuit contactor. It is a vacuum contactor. It has hrc fuse for protection against short circuit and have vacuum bottles in which contacts move to get close and open. It will never trip bcas it does not have tripping mechanism, it does not have operating mechanism. It's contacts are made only to make and break normal current. It is used to start and stop a motor only. It does not have ka rating for fault current. Vacuum circuit breaker is a real fault current breaker which trips during a fault like short circuit, earth fault, under or over voltage or any one. It encompasses the operating mechanism to break the contacts at a very high speed and also need a spring charging mechanism to turn the breaker on. It has very highly rated contacts inside a heavy capacity vacuum bottles. It has realese ( something like solenoid ) which pulls the plunger after it get signals from various protection relays in case of fault. It is not meant to operate for day to day start and stop operation of motor. It has ka rating for fault current. Analogus to ordinary home circuit, vcb is like a circuit breaker at home inside a panel and vc is a relay in our any of instruments at home. Analogus to low voltage situation, vcb is like a fault current ( air, or bulk oil or minimum oil ) circut breaker and vc is like an ordinary contactor
ka of mccb=transformer(KVA)x100/1.732xsecondary voltagex%impedence of transformer
It was replaced by "Everyone" in 1998.