The miniature circuit breaker or MCB accessories enhance the functionality of MCBs in various ways. In addition to the basic on/off function, MCBs may also offer features such as overcurrent and thermal protection, current limiting, and circuit breaker status indication. The following are five common MCB accessories that can be used to improve the performance of your circuit breaker:

MCB Accessories

MCB accessories are devices that can be attached to an MCB in order to increase its functionality. Although they are not essential for the proper functioning of the MCB, they can be very useful in certain applications.

Among the most important MCB accessories are shunt trips, alarm contacts, auxiliary switches, and surge protection devices such as under-voltage/overvoltage release modules. Here is a look at each of these accessories and how they can be used.

1. MCB Shunt Trip

A shunt trip is an accessory that can be added to an MCB to provide remote control of the circuit MCB breaker. It’s typically used in applications where the breaker needs to be opened or closed remotely, such as in a fire alarm system.

The MCB shunt trip features a set of contacts that can be opened or closed by an external signal, such as a voltage or current. When the contacts are open, the circuit breaker is de-energized and can no longer conduct electricity.

The use of a shunt trip with MCB can improve the safety of a circuit by allowing the breaker to be de-energized remotely in the event of an emergency or during maintenance situations.

2. MCB Auxiliary Contact

The MCB auxiliary contact is used to remotely provide a status indication of the circuit breaker. It provides a convenient way to know if the circuit breaker is open or closed, without having to physically inspect the breaker.

These MCB accessories consist of a set of contacts that are operated by the main contacts of the circuit breaker. When the main contacts are open, the breaker auxiliary contacts are also open.

The addition of an auxiliary contact to an MCB circuit breaker helps improve the safety of a circuit by providing the status of the breaker’s position at any time.

3. MCB Trip Alarm

An MCB trip alarm is an accessory that is used with an MCB to provide a visual or audible indication when the breaker trips. It comes in useful in situations where it is important to know when the circuit breaker has been activated.

These MCB accessories are typically located next to the breaker. When the breaker trips, the contacts will change state, providing a visual or audible indication that the breaker has been activated.

Alarm modules improve the safety of a circuit by providing an early warning that the breaker has been activated. They also enhance circuit efficiency by allowing operators to know when the breaker has been activated and needs to be reset.

4. MCB Under/Overvoltage Device

An under/overvoltage module is usually added to an MCB to provide protection against voltage fluctuations. As such, it’s mostly useful in applications where the circuit may be subject to brownouts or other voltage dips and surges.

The module monitors the voltage of the circuit and trips the breaker when the voltage falls below or rises above a certain level. This serves to protect devices in the circuit from damage due to voltage fluctuations.

When used with a miniature circuit breaker, these MCB accessories make circuits more resistant to voltage fluctuations and can help prolong the life of devices in the circuit.

5. MCB Busbar

The MCB busbar system or link system is primarily used to provide more flexibility in the way the breaker is installed. These accessories typically consist of a set of busbars that are connected to the breaker and run to the load side of the circuit.

The MCB busbar arrangement allows the breaker to be installed in a variety of locations, including. It also allows the breaker to be easily removed and replaced if necessary.

Ideally, the MCB busbar link reduces the amount of wiring that is required, and it makes the installation of the miniature circuit breaker more flexible.

6. MCB Lock Off

MCB lock-off devices prevent the breaker from being turned on inadvertently. They help to ensure that the breaker is not accidentally energized to endanger lives, such as in a circuit that is being serviced.

An MCB lock-off works by providing a means to physically block the breaker from being turned on. They are usually installed on the front of the breaker and can be engaged or disengaged as needed.

MCB lock-out devices improve the safety of a circuit by ensuring that the breaker cannot be accidentally energized. You get to secure a breaker using a padlock, ensuring that no one can energize it until you’re ready.

Tips for MCB Accessories

1. When choosing accessories for an MCB, be sure to select the appropriate size and type for the application. MCBS comes in a variety of sizes, and not all accessories will fit all MCBs.

2. Be sure to follow the manufacturer’s instructions when installing MCB accessories. Improper installation can result in damage to the breaker or the accessory and may void the warranty.

3. If an MCB accessory is not working as intended, be sure to check the manufacturer’s troubleshooting guide before replacing the entire breaker. Many problems can be resolved without replacing the entire unit.

4. You can add MCB accessories to a panel at any time, but it is best to install them when the breaker is first installed. This will ensure that the breaker and accessories are compatible and that the installation is done correctly.

5. When adding accessories to a miniature circuit breaker, be sure to follow all local codes and regulations. Improper installation of electrical components can be dangerous and is often against the law.

Conclusion

Without accessories, a miniature circuit breaker’s ability is only limited to short circuit and overload protection. MCB accessories increase the functionality by providing features such as remote control, alarm indication, or even protection against voltage surges. We hope this article has helped you understand what MCB accessories are available and how they can be used to improve the functionality of your circuit breaker.