MCCB is the abbreviation for Molded Case Circuit Breaker. It is an important type of electrical protection used when the load current crosses the limitation of a miniature circuit breaker, also called MCB. The MCCB offers safety against overload and short circuit faults, which are extensively used for switching the circuits. It can be used in devices of any current rating that needs adjustable trip settings. This is usually not found in MCBs and plug-in circuit breakers.
MCCB has a broad range of voltages and frequencies of 50 Hz and 60 Hz. This makes an apt choice for industrial usage as well. Some of the general applications cover safeguarding capacitor banks, generators, and central electric feeder distribution. It also provides adequate security if an application requires isolation, adjustable overload settings, and earth fault protection.
The crucial difference between moulded case circuit breaker and the miniature circuit breaker is that an MCCB can offer current ratings of up to 2500 amperes and provides adjustable trip settings. Some other key differences between these 2 types of circuit breakers are as mentioned below:
MCB’s are generally used for the safety of the system from overload, while an MCCB is used to secure it from short-circuits and overheating.
The MCB comes with a fixed tripping circuit while it is moveable for MCCB.
The MCB has different versions of single, two, or three-pole. MCCB comes with single, two, three or four-pole versions.
An MCB has a current rating of 100 amps, whereas an MCCB is 10 – 200 amps.
An MCB is primarily used in low current circuits, whereas MCCB’s are preferred for heavy current circuits.
An MCB is widely used in residential settings, whereas MCCB’s opted for large-scale industrial purposes.
Functions of An MCCB
Just like any other circuit breaker, MCCB is the following 3 vital functions:
It offers security against overload currents that are above the specified value. Such currents also tend to last longer than the standard period for applications. MCCB is crucial to maintain the health of the system in such cases.
It is also imperative while maintaining the system's safety during a short circuit or a line fault. Since such conditions result in very high currents, MCCBs act spontaneously to interrupt them instantly.
Whenever there is a shortage of manual switching scope, MCCB can turn a current on or off. This is, however, less common usage of an MCCB.
Due to these features, MCCBs are widely used for motor safety, capacitor bank protection, protection of generators, primary electric feeder protection, welding usage, and low current applications that need adjustable trip settings.
Users should look at some essential factors in an MCCB before investing in them. These factors include rated frame current, which is nothing but the highest current value according to the design of the MCCB. They should also look into the rated current, rated insulation voltage, rated working voltage, operating short circuit breaking capacity, the ultimate short circuit breaking capacity or Icu. Buyers must also check into the mechanical and electrical longevity of the MCCB.
#Schneider Electric India has some of the best range of MCCBs, which are very popular for residential and commercial purposes. They are excellent in quality and highly durable.