How MCB Work ?
In this post, we will find out a unique way to Understand – How MCB Work ? So let’s Start, An MCB is a little, intriguing gadget that protects you and your home from electrical problems. This breaker protects you from two eventualities.
- First, there’s a short circuit,
- and then there’s an overload.
In the event of a short circuit, the MCB trips in under three milliseconds, isolating the internal connections.
How this smart device detects current chaos so quickly and precisely?
How does this system recognize the occurrence of an electric fault?
Let’s start by looking at how we can construct a super-fast triggering mechanism that opens wide; a creative technique to accomplish this goal is shown here. As depicted, this device has a lever to which a rectangular ring is attached. In this arrangement, two springs and a central lever join the rectangular ring.
When the lever is moved up, the bottom spring compresses and the top spring expands. The forces of both of these springs are eventually transferred to the liver via the rectangular ring, and this force is in the upward direction.
As you can see, the rectangular ring is originally displaced from the center of the lever, therefore the torque created by the force acting on the rectangular ring is clockwise. If you release the lever in this position, the clockwise torque will return the lever to its original position.
However, if you push the lever higher, you’ll notice that the offset distance suddenly becomes positive, indicating that after a critical limit, the torque will act on it in a counterclockwise direction, and when the MCB is turned on, the structure of the MCB will prevent the lever from rotating any further counterclockwise.
Now, if an external trigger twists the lever slightly clockwise, the torque on the lever changes and the circuit opens wide quickly without the need for an external force.
As the operator lowers the lever, you can see how the mechanism works in super slow motion. After a little angle, the lever generates its own torque, and there is no need to add external power. Now the only question is whether the mechanism works in practice.
How can we generate this small input trigger or input motion when a fault occurs?
The best solution is to use an electromagnet; this coil produces magnetic fields that are proportional to the current passing through it; as the current increases, the magnetic field becomes stronger throughout the Post; note that in the case of a short circuit, the current can rise by a thousand times in magnitude in milliseconds.
An iron cylinder and pin are put inside this electromagnet on a spring slightly offset from its center, generating an extremely strong magnetic field. The powerful magnetic field pushes the cylinder downward, pushing the pin. This slight movement of the pin is the mechanism’s input trigger, and it causes the circuit to open, as we mentioned earlier.
let’s see why
Heat causes the strip to bend slowly as the current rises, which pulls a c-shaped lever and therefore the main lever down, opening the contacts. The current value at which the bi-metallic strip should work can be modified with this screw, which is only set by manufacturers. Apart from the MCB, we offer additional breaker types built for different types of failures. We hope you now have a thorough grasp of a micro breaker. With this properly engineered device, you are secure from electrical calamities.