Difference Between MCB, MCCB, ELCB, RCCB And Its Characteristics

Electrical circuit breaker is a one kind of switching device which can be activated automatically as well as manually to control and protect an electrical power system respectively. As the current power system deals with vast currents, the special notice should be given throughout designing of circuit breaker to secure break of arc produced during the process of the circuit breaker. This was the fundamental definition of circuit breakers. These have been divided into a various types based on special categories they have been subdivided into.

Difference Between MCB and MCCB, ELCB, RCCB

The different circuit breakers and difference between MCB and MCCB, ELCB and RCCB are discussed below.

MCB-Miniature Circuit Breaker

MCB is an electromechanical device which guards an electrical circuit from an over current, that may effect from short circuit, overload or imperfect design. This is a better option to a Fuse since it doesn’t require alternate once an overload is identified. An MCB can be simply rearranged and thus gives a better operational protection and greater handiness without incurring huge operating cost. The operating principle of MCB is simple.

Miniature Circuit Breaker
Miniature Circuit Breaker

An MCB function by interrupting the stability of electrical flow through the circuit once an error is detected. In simple conditions this circuit breaker is a switch which routinely turns off when the current flows through it and passes the maximum acceptable limit. Generally, these are designed to guard against over current and overheating.

MCB is substituting the rewirable switch-fuse units for low power domestic and industrial applications in a very quick manner. In wiring system, the MCB is a blend of all three functions such as protection of short circuit, overload and switching. Protection of overload by using a bimetallic strip & short circuit protection by used solenoid.

These are obtainable in different pole versions like single, double, triple pole & four poles with neutral poles if necessary. The normal current rating is ranges from 0.5-63 A with a symmetrical short circuit breaking capacity of 3-10 KA, at a voltage level of 230 or 440V.


Characteristics of MCB

The characteristics of an MCB mainly include the following

  • Rated current is not more than 100 amperes
  • Normally, trip characteristics are not adjustable
  • Thermal/thermal magnetic operation

MCCB-Molded Case Circuit Breaker

The MCCB is used to control electric energy in distribution n/k and is having short circuit and overload protection. This circuit Breaker is an electromechanical device which guards a circuit from short circuit and over current. They offer short circuit and over current protection for circuits ranges from 63 Amps-3000 Amps. The primary functions of MCCB is to give a means to manually open a circuit, automatically open a circuit under short circuit or overload conditions. In an electrical circuit, the over current may result faulty design

Molded Case Circuit Breaker
Molded Case Circuit Breaker

The MCCB is an option to a fuse since it doesn’t need an alternate once an overload is noticed. Unlike a fuse, this circuit breaker can be simply reset after a mistake and offers enhanced operator safety and ease without acquiring operating cost. Generally, these circuits have thermal current for over current and the magnetic element for short circuit release to work faster.

Characteristics of MCCB

The characteristics of an MCCB mainly include the following

  • The range of rated current us up to 1000 amperes
  • Trip current may be adjusted
  • Thermal/thermal magnetic operation

ELCB -Earth Leakage Circuit Breaker

The ELCB is used to protect the circuit from the electrical leakage. When someone gets an electric shock, then this circuit breaker cuts off the power at the time of 0.1 secs for protecting the personal safety and avoiding the gear from the circuit against short circuit and overload.

Earth Leakage Circuit Breaker
Earth Leakage Circuit Breaker

ELCB is a security device used in electrical system with high Earth impedance to avoid shock. It notices small stray voltages on the metal fields of electrical gear, and interrupt the circuit if an unsafe voltage is detected. The main principle of Earth leakage protectors is to stop injury to humans and nature due to electric shock.

This circuit breaker is a specialized kind of latching relay that has structures incoming mains power connected through its switching contacts so that this circuit breaker disconnects the power supply in an unsafe condition.

The ELCB notices fault currents from live to the ground wire inside the installation it guards. If enough voltage emerges across the sense coil in the circuit breaker, it will turn off the supply, and stay off until reset by hand. A voltage-sensing earth leakage circuit breaker doesn’t detect fault currents from exist to any other ground body.

Characteristics of ELCB

The characteristics of an ELCB mainly include the following

  • This circuit breaker connects the phase, earth wire and neutral
  • The working of this circuit breaker depends on current leakage

RCCB (Residual Current Circuit Breaker)

A RCCB is an essential current sensing equipment used to guard a low voltage circuit from the fault. It comprises of a switch device used to turn off the circuit when a fault occurs in the circuit. RCCB is aimed at guarding a person from the electrical shocks. Fires and electrocution are caused due to the wrong wiring or any earth faults. This type of circuit breaker is used in situations where there is a sudden shock or fault happening in the circuit.

Residual Current Circuit Breaker
Residual Current Circuit Breaker

For instance, a person suddenly enters in contact with an open live wire in an electrical circuit. In that situation, in the absence of this circuit breaker, a ground fault may occur and an individual is at the hazardous situation of receiving a shock. But, if the similar circuit is defended with the circuit breaker, it will tour the circuit in a second therefore, avoiding a person from the electric shock. Therefore, this circuit breaker is good to install in an electrical circuit.

Characteristics of RCCB

The characteristics of an RCCB mainly include the following

  • Both wires phase and neutral are connected through RCCB
  • Whenever there is any ground fault occurs, then it trips the circuit
  • The amount of current supplies through the line should go back through neutral
  • These are a very effective type of shock protection

Thus, this is all about what is circuit breaker, the difference between MCB, MCCB, ELCB, RCCB & Its characteristics. Furthermore, any queries regarding this concept or to implement electrical projects, please give your suggestions, ideas and feedback by commenting in the comment section below. Here is a question for you, what is the main function of a circuit breaker?

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  1. victor ochieng says:

    you’ve made me know the types of breakers and there uses.

    1. Tarun Agarwal says:

      Hi victor ochieng
      Thank you so much for your kind words

    1. Tarun Agarwal says:

      Hi Rahmad Azly
      You’re welcome

    1. i understand MCB,MCCB,ELCB.
      full explanation for RCCB .With video link send me .

      1. Tarun Agarwal says:

        Hi Sakthi
        We are very sorry to inform you that we cannot provide you the video link.

  2. If a ELCB trips is it possible to tell which CB (I have four in my house) is the faulty circuit? This would help me to narrow my search to find the problem area.

  3. Can ELCB and RCCB protect over overload and short circuit faults?

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