Residual Current Circuit Breaker

Residual Current Circuit Breaker-RCCB

Have you ever heard about various residual current devices RCD? Do you know why they are used? Have you ever thought about the full form of RCCB in electricity?

If you need answers to these questions, keep reading our latest article to know about RCCB.

First of all, let us tell you the full form of RCCB.

Full Form of RCCB

There are several residual current devices RCD like RCB, RCCB, MCB, MCCB, ELCB, etc. This article is about RCCB, which is the abbreviation of residual current circuit breaker.

What is RCCB?

Residual current circuit breaker is an electrical safety device that breaks the electrical circuit with the current leakage to ground. It is a vital component that protects equipment and people from damages from electric shocks. These devices reduce and minimize the risk of danger and serious accidents. You can easily check if your residual current circuit breaker is on or off. When it is off, its color would be green and when it is on, its color would be red.

How does the RCCB work?

Did you study Kirchhoff’s law? RCCB works according to this law. If you never studied this law, we will explain it first. Kirchhoff’s current law explains that incoming current must be equal to the outgoing current in the circuit. RCCB compares both currents and checks the difference between incoming and outgoing current. If the current value in the live wire is different from the current value in the neutral wire, the fault occurs. The difference of the current is the residual current. RCCB senses it immediately and trips the circuit. In this way the electrical supply switches off.

Types of RCCB

There are two kinds of residual current circuit breakers as given below;

  • 2 pole RCCB
  • 4 pole RCCB

Both devices work on the same principle in the same manner. Let’s discuss both kinds of RCCBs briefly.

2 Pole RCCB

You can use this kind of residual current circuit breaker for single phase supply. A single phase supply connection typically has a live and a neutral wire. It has two ends with which both wires are attached. You can switch these devices on and off through a built-in rotary switch. You can test your device with a built-in test button for reliability and smooth functionality of these devices.

4 Pole RCCB

4 pole residual current circuit breakers are used in case of three phase electric supply connection. These devices have neutral and three phase wires. Just kike two pole RCCB, it also have two ends through which neutral and three phase wires are attached.

Importance of RCCB

Residual current circuit breakers are extremely important as they provide real time protection for electrical devices and circuits. They are the best option to use at industrial locations and setups that require high voltage at commercial level. Risks are always there and there might be accidents, damages, and serious harm to the appliances, equipment, and people.

Rating and Sensitivity

Current rating for RCCBs ranges from 10 amp to 100 amp and the sensitivity is usually 30, 100, and 300 amp. When the current goes above the sensitivity rate, it disconnects the supply to avoid any short circuit conditions.

Uses of RCCB

Lets get familiar with the uses of residual current circuit breakers.

Residual current circuit breakers are used as safety measures for protection of electrical appliances and circuits. These devices are able to sense the current in the circuits. When the current ratio increases and there is any fault, these devices sense and automatically disconnect the circuits and electrical supply.

Benefits of RCCB

There are a lot of key benefits associated with the residual current circuit breakers. Here are a few benefits mentioned below;

  • Residual current circuit breakers provide protection against earth fault and current leakage issues.
  • They also protect against voltage problems.
  • RCCB has a filtering device that acts as a safety tool against voltage problems.
  • When the current is more than the desired limit, it automatically senses and disconnects it.
  • These devices offer dual termination for connections.
  • These devices are used both for cable and busbar connections.

Disadvantages of RCCB

Alongwith the several benefits of RCCB, there are disadvantages too.

  • If the loads generate standard wave forms, then residual current circuit breaker gives no guarantee that they will operate. The main reason behind this is that manufacturers of these devices have made them work efficiently in case of normal wave forms of the electrical supply.
  • These devices are unable to protect overload situations. They can only protect when both currents are different. If the live and neutral currents are different then RCCBs can detect them easily.
  • If you have installed RCCB devices, you might face unwanted tripping. This happens typically in old applications and appliances because of the small flow of the current to the earth. This causes a sudden change to the electrical supply and the load of the current.
  • If the conductors are loose and the crews are not tight to the connections, they get heated. This causes an overheating problem and residual current circuit breakers do not provide protection in such cases.
  • Residual current circuit breaker devices do not provide protection against few kinds of shocks especially line neutral shock. There is a balanced current in those lines. This balance is because of the togetherness of both electric terminals.

Important Tip to Buy RCCBs

There are a lot of brands providing the best and reliable devices across the nation. It is highly recommended that you select a brand that is reliable and good in all aspects. You can ask your friends and family members for recommendations. You can also check online for the previous customer reviews and ratings for a brand. It is necessary to choose a device that is durable, reliable, and lasts for a longer time.

Testing Method for Your RCCBs

It is very easy to test residual current circuit breakers. There is a test circuit attached to the device that ensures the reliability. When you push the test button, current flows from the test circuit. If there is any imbalance on the neutral wire, RCCB will trip and supply will be stopped.

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