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#Copytrans contacts serial breaker full

In this method, the arc resistance is kept low until the current becomes zero where arc extinguishes naturally and prevents it from restriking. The arc extinguishes naturally and prevents it from restriking. Low Resistance Method or Current Zero method:ĪC circuit breakers use low resistance method, the arc resistance is kept low until the current becomes zero.

To increase the resistance of arc we can: This interrupts the current between the contacts and extinguishes the arc. They are:ĭC circuit breakers use a high resistance method, by increasing the arc resistance the current will reduce to a value that becomes insufficient to maintain the arc. There are two methods available for arc extinguishing. It is important and necessary to extinguish the arc in a short period.

Cross-Section of arc: The arc resistance is large if the area of the cross-section of the arc is less.

More the length more is the arc resistance

Length of arc: This length is the separation between the contacts.

Degree of ionization: The arc resistance increases if there are a smaller number of ionized particles between the contacts.

The arc resistance depends on the following: Greater the arc resistance, the smaller the current flows between the contacts. The current flowing between the contacts depends upon the arc resistance. This interrupts the current in the circuit until the arc extinguishes. The potential difference between the contacts is enough to maintain the arc which provides a low resistance path. The oil acts as a conductor and forms an arc between the contacts. This produces heat in the medium to ionize the air or oil. The circuit breaker has a medium (air or oil depends upon the circuit breaker) between the contacts. As soon as the contacts begin separating, the contact area decreases which will increase the current density and a rise in the temperature. Under abnormal conditions, heavy current flows through the contacts. Before the heat generated by arc causes damage, the circuit breaker needs to extinguish the arc quenching mechanism in a short period. It generates excess heat because the resistance of the arc is high and it may cause damage to the system. The separation of contacts between the opened contacts will continue until the discharge ceases. When a fault occurs on any part of the system, the trip coils of the circuit breaker get energizes and the internal mechanism makes the moving contact move away from the fixed contacts and opens the circuit. Whenever there is an abnormal condition or there is a fault in the system the contact will open (either automatically or manually).

Under normal conditions, the contacts will not open and it remains closed. The trip coil is responsible for the proper working of the circuit breaker. The automatic mechanism provides the means of opening and closing the circuit automatically. Different components are enclosed and mounted in a molded case frame. The outer frame is rigid, strong which is an insulated housing. It consists of fixed and sliding (moving) contacts called electrodes. They are:Ĭontacts, Outer Frame, Automatic mechanism, Trip coil, and Arc quenching medium The construction of the circuit breaker has the following important parts.

Once the breaker trips, a switch is there to reset the circuit. The advantage of a circuit breaker is, when a fault or excessive amount of current flows through the circuit, it will interrupt the flow of current. The major difference between the circuit breaker and fuse is: Fuse can be used once and needs to be replaced while the circuit breaker is reusable even after the occurrence of the fault. Halt the circuit during short circuit or fault.To interrupt capacitive currents and small inductive currents.Break a circuit automatically when there is an overcurrent condition.Make or break the circuit during normal conditions.

#Copytrans contacts serial breaker full

It is an electrical switch that can operate either manually or automatically under no-load, full load or short circuit conditions. There are different types of circuit breakers available to protect the electrical components and system from faults such as overload, earth, and short circuit. By definition, a Circuit breaker is a mechanical device that isolates the faulty system from a healthy system of the power system by opening or closing the circuit.