How to Install a Residual Current Circuit Breaker (RCCB)?

A residual current circuit breaker (RCCB) is an electrical safety device that identifies and trips an electrical circuit when current leaks to the ground. This device is used in houses and buildings to keep individuals and electrical systems safe from electrical fires, shocks, and other risks caused by defective wiring, current failure, insulation, or unintentional contact with live parts.

Our lives cannot function without electricity. Thus, ensuring electrical safety has to be a priority, and it is essential to install RCCB. Lauritz Knudsen (Formerly L&T Switchgear) offers a wide range of electrical safety devices. The RCCBs are one of the best-selling products of Lauritz Knudsen (Formerly L&T Switchgear). The RCCBs are ergonomically designed, enabling electrical safety of the highest standards. If you need to know how to install RCCB, along with its mechanism, advantages, and disadvantages, read the following segments.

Why Residual Current Circuit Breakers Are Used?

Before analysing the use of RCCB, let’s understand what is RCCB in electrical. It is a compact protective device that safeguards electrical systems and buildings from catching fire or shocks due to electrical failure or leakage of current through the ground. For an RCCB connection, the device should be used in a series with a fuse to safeguard the other electrical equipment from potentially damaging thermal and dynamic shocks due to excess currents.

What is the use of RCCB? In simple terms, these electrical devices ensure the safety of all electrical devices. When there is an excess flow of current through the ground, these devices break the entire circuit so that the electrical systems remain protected from shocks or potential fires.

How to Install an RCCB?

Many people think that the answer to how to install RCCB is complicated. It is actually a simple process. Follow the steps below and find out.

Turn off the core power supply to disconnect the circuit that requires protection from the RCCB.
From the supply side, attach the live wires to the input terminals of the residual current circuit breaker, typically marked as L1, L2 and L3.
Connect the neutral wires from the main power to the RCCB's output terminals, which are usually designated as L1, L2, and L3.
Link the neutral wire from the load side to the RCCB’s output terminal, which is marked as N.
Make sure all the connections are tightly secured and there are no loose ends or exposed wires.
To test the effectiveness of the RCCB installation, turn on the main power supply by pushing the test button. The RCCB should break and disconnect the circuit. If that doesn’t happen, then it can signify a wiring error or damaged components. So, repair them before using the circuit.
If you need to reset the RCCB, hit the reset button. The device will shut down and reconnect the circuit. If not, there must be a wiring error or damaged components. Repair the parts before utilising the circuit.

How RCCB Works?

How does a RCCB work? Here’s how it does. An RCCB works on the principle of Kirchhoff’s current law. This law states that the total amount of current entering a node equals the total amount of currents exiting a node. In normal circuits, the current going through the live and neutral wires is equal and opposite. However, if there’s a fault in the circuit, for instance, a person touching the live wire or broken insulation, a part of the current gets diverted to the earth's surface via an alternate channel. This causes a disparity between live and neutral wires. The RCCB senses this gap and causes the circuit to break within a few seconds.

An RCCB is made up of a toroidal transformer consisting of three coils: one for live wire, one for neutral, and the other for sensing. These components together answer the question of how an RCCB works.

When the currents flowing through the wires are balanced, the magnetic fluxes from live and neutral coils are equal and opposing. When there’s an imbalance in the currents, a residual magnetic flux is produced, causing a voltage in the sensor coil. This voltage triggers a relay, which opens the contacts of the RCCB and disconnects the circuit.

An RCCB also comes with a test button that allows users to test its operation by generating a small amount of leakage current in the circuit. When you hit the test button, the live wire is connected on the load side to the supply neutral, bypassing the RCCB’s neutral coil. This results in an imbalance in currents and fluxes, allowing the RCCB to break the circuit. If it does not, it indicates that the RCCB is defective or wrongly connected and must be replaced or fixed.

What Are the Advantages and Disadvantages of Residual Current Breakers?

There are various RCCB advantages and disadvantages. First, let’s learn about the advantages:

A residual current circuit breaker safeguards electrical equipment from fires and other potential damages by promptly detecting and interrupting circuit faults.
These devices prevent electric shocks by detecting current leakage as low as 10mA.
RCCBs can work with a variety of loads and currents (DC, AC, and high frequency).
These devices are simple to install and use as they have only two buttons: test and reset.
RCCBs act like the main disconnecting devices for MCBs or miniature circuit breakers.

Despite all these advantages, RCCBs also have certain demerits. These are:

These are more expensive than other protective devices like MCBs and fuses.
They cannot offer protection against short circuits or overcurrents that cause wires to overheat or melt.
RCCBs may fail to break the current flow due to internal problems like wear, mechanical jamming, or corrosion. This may jeopardise the safety of the circuit and its users.
RCCBs can trip unintentionally due to extrinsic sources like capacitive coupling, lightning and electromagnetic interference. This can cause loss of productivity and inconvenience.

Types of RCCBs

Depending on the sensitivity and leakage currents, there are different types of RCCBs.

Type AC: This RCCB reacts only to AC currents. This type can be used in devices that do not produce pulsing or direct currents.
Type A: This kind of RCCB reacts to both AC and DC currents. It can be used in electrical equipment that produces rectified currents, such as TVs, LED lights, and computers.
Type B: This RCCB is sensitive to AC, smooth and pulsating DC currents. It is appropriate for use with equipment that creates smooth DC currents, for instance, battery chargers, electric automobiles and solar inverters.

There is another classification of residual current circuit breakers based on the number of poles.

2-pole: This kind of RCCB has two slots, one linked to the live wire and the other to the neutral wire. It is suitable for single-phase circuits.
4-pole: This kind contains four slots that link three live wires and one neutral wire. It is suitable for three-phase circuits.

Also Read: MCB Installation Guide For Home And Office

Conclusion

To ensure your electrical systems are properly secured from any potential dangers, it is essential to integrate residual current circuit breakers. These are easy to install and offer just two buttons: test and reset, which verifies the device’s operational strength and resets the mechanism when it detects any potential danger, causing the circuit to trip. If you’re looking for good-quality protective devices to protect your electrical devices from potential shocks or fire, Lauritz Knudsen (Formerly L&T Switchgear) Smartshop brings you different RCCBs based on sensitivity and current leakage. Furthermore, it has various kinds of MCBs and fuses that serve the same purpose. Navigate through the Smartshop and find electrical products in many categories that will be delivered to the comfort of your home.

June 19, 2024