What Is RCD, RCB, Or RCCB?

31st Jan 2022

What is RCD?

Often short circuits happen in households. In most cases when a circuit is cut by any reason or produces a loop with itself, then too much current starts flowing. This incident is known as a short circuit.

When a short circuit happens, as too much current starts flowing, it can cause damage to electrical machines, can be a reason for electrical shock due to touching, or can cause a fire. That’s why protecting your house from these unwanted guests is required. To do this, RCD can help you out. Residual Current Device will protect your house.

Definition of RCD

RCD or Residual Current Device is an electrical instrument whose prime function is to cut the connection when a short circuit is being spotted. When a short circuit and leakage is being found, it cuts the connection from the spotted area of electrocution and electrical fire with the electrical devices. Thus the area is being separated and can’t harm anything else.

What’s The Working Function of Residual Current Device?

RCD is a device that maintains a simple flow of current. It is appropriate because it maintains the balance of the current between source and machines. There is a transformer, used in this case. It is called a core balance transformer. It has two windings. Primary winding and secondary winding. The secondary winding is very sensitive. As primary winding is connected to the source, it can easily detect the faults in the current flow.

So when faults will be detected, no further current will flow to the electric devices through the secondary winding. The leakage will be sensed by the core when the electric flux will penetrate it. There is a fixed ratio of the current flow. When it goes up with 60 to 80% power, then it symbolizes risks. As it is done automatically, installing it will be beneficial.

Why Installing RCD is Important for Your House or Industry?

One of the important cases is being discussed above. In many cases when a short circuit happens, a rapid amount of electricity passes through the wires and can cause huge destruction to the device. But other than that, it can cause body current to the device. Again, in industrial places, more than one machine is connected to the same power source. Even some machines are directly connected to other machines. So can you imagine what will happen when a sudden fault appears on the power source? It will hamper everything, will cause a huge loss, and sometimes fire is the end result.

Fuses and circuit breakers are great salvations. But these are not enough. Why? Because though these are good to make a path for the excessive current flow, it can’t help when a man touches the current source. In easy words, the current will flow to the earth through the human body by destroying his life. RCD can help you. As it is very sensitive before the current rises, it will help you to protect yourself and your machines. So, RCD is an essential thing to install. Don’t push your luck, allow it and live a safer life.

What is RCB or RCCB?

TSL1-63 Residual Current Circuit Breaker
  • RCB and RCCB can be different in abbreviations but they are basically the same things. RCB stands for Residual Circuit Breaker and RCCB stands for Residual Current Circuit Breaker. It is used as a circuit breaker in residential places to save your electrical devices from massive destruction due to a high voltage supply. High voltage or high current whatever it is if those are being generated due to sudden faults. Through this discussion, you’ll be given some beneficial points to install it. Those are as follows.
  • RCCB is a great thing to protect human lives. It is true that it is a circuit breaker and it breaks the circuit when overload happens. But its prime focus is to protect human lives only. It can disconnect the current source but can’t reduce the damage completely.
  • You can say it is a negative point about RCCB or RCD. It can’t help you when a short circuit happens. The configuration of this device is so simple. And it has light components within it. So it can’t help to rescue your devices. It will insulate the machines’ bodies so that no shock will be raised.
  • RCCB’s prime objective is to protect a household from dynamic stress and thermal damages. Do you know RCCB is a wide device? It is wide because the series connections here are made with special modifications. Whatever you have MCB or Fuse, it will be adjusted with any device.
  • RCCB has a very low price. As it has the simplest configuration ever, you can have it at a very short price. You can even use it in industrial areas apart from residential places. It is very easy to install. A basic level of knowledge regarding wiring can help you with this.

What’s The Importance of RCCB or RCD?

Probably, you are questioning yourself what’s the importance of the device when it is not protecting any devices? There are many rural areas where people with not too much worth are living their lives. All of them have ambitions to grow, ambition to stand upon their feet. Electricity always matters. So in such a situation applying other expensive devices won’t be possible for them. For them, for the time being, RCCB can be a great help. So, it is recommended to install an RCCB at home.

Here’s a video on Differences between RCD – RCCB and RCBO, i hope it will be helpful for you.


Every device is playing its role. Whether it is RCCB, RCBo, MCB, or RCD. Everything has separate working functions. But the ambition of all these devices is the same. To protect human life. All of these electrical devices are easy to install and highly protective.

So, hire an electrician to install it right now. Don’t do any delay as it can lead your or others’ lives to an unwanted end. Know the Differences between all the devices, check out your budget, know your needs according to industrial pressure or household capacity, then select the perfect one.

We have more than 31 years experience

Our Strength


Request a Quote