Magnetic Circuit Breaker Has Trip Action

Thermal magnetic tripping units the thermomagnetic trip unit consists of two parts.

Magnetic circuit breaker has trip action.

The magnetic field moves a switch tripping the breaker and clearing the fault. So in case of a magnetic circuit breaker a solenoid or an electromagnet is attached to the trip unit. If the current suddenly or rapidly increases enough the magnetic element will attract the trip bar release the latch and the circuit breaker will trip as shown in figure 2 21 view c. A magnetic circuit has effective iron length of 100 cm and it is wound with 800 turns of wire carries 1 a.

The high current induces a very strong magnetic field in a coil inside the circuit breaker. Find the magnetic field strength. This trip unit is intended for the protection against overloads. Asked in switchgear and protection by questionanswer.

This is done when the current passes through the solenoid magnetism develops in it due to changing magnetic flux and a magnetic field is created around the solenoid. The magnetic trip unit made up by an electromagnetic device with fixed fixed. Magnetic circuit breaker has trip action. When a short circuit occurs the current flowing through the circuit conductor causes the magnetic field strength of the electromagnet to increase rapidly and attract the armature as shown in fig.

Overloaded circuits loose or faulty wiring and lightning can cause the circuit breaker to trip. There are other devices able to break a circuit during a surge or short circuit each with its own limitations. A delayed b instantaneous c both of the above d none of the above. Phase to phase single phase to ground double phase to ground three phase short circuit in a contactor interrupting medium may be air oil sf 6 gas any of the above.

Magnetic circuit breaker has trip action. The magnetic protection mechanism is calibrated to trip with high magnitude fault currents but does not respond to. Thermal circuit breaker has delayed trip action instantaneous trip action both of the above none of the above gives rise to symmetrical fault. The circuit breaker will trip as shown in figure 2 21 view b.

Charging action of capacitor. The trip unit is the part of the circuit breaker that determines when the contacts will open automatically. This circuit breaker has tripped even though the thermal element has not had time to react to. Short circuit trip action uses an electromagnet having a winding that s in series with the load current.

The function of the solenoid or the trip unit is to generate a magnetic field.