It is another type of electrical protection device which is used when load current exceeds the limit of a miniature circuit breaker. The MCCB provides protection against overload, short circuit faults and is also used for switching the circuits. It can be used for higher current rating and fault level even in domestic applications. The wide current ratings and high breaking capacity in MCCB find their use in industrial applications. MCCB can be used for protection of capacitor bank, generator protection and main electric feeder distribution.
It offers adequate protection whenever an application requires discrimination, adjustable overload setting or earth fault protection. The device is also supposed to be maintained properly. Also pollution degree is to be 3 or more. These circuit breakers are industrial applications and protect the power distribution of up to volts AC.
So it is clear that these items are different in their fundamentals. An MCB designed for indoor, pollution-free conditions and would not be suitable for harsh, outdoor applications that require pollution degree 3.
Typically, IEC certified Circuit Breakers meet minimally required performance to proof proper protection of household installations: Pollution degree 2, impulse voltage 4kV, isolation voltage is the same as nominal voltage V. That is the reason why usually we meet limited number of technical information printed on Circuit Breakers.
Rating of same MCB can be different for different standards, so, it is highly recommended to check the data properly printed on it. So, the application and needs will decide that which device is to be used or selected.
As we have cleared everything in the above sections as well as, the MCB nameplate rating data also give an appropriate information, but the choice of MCB or MCCB is based on certain factors and conditions like;. Below are types of MCBs which shows the magnetic fault protection. Also, to prevent the accidental overloading of the cable at no fault, there is a thermal device in MCB to eliminate the chances of unwanted tripping operation of MCB.
For short circuit protection in home appliances, the current rating is about to 6kA while for heavy and industrial operation, it is above the 10kA. The needs of these devices arise because of the number increasing in injuries as well as deaths because of electric shock. When the live wire accidentally touches the metallic body of the connected device or appliance, then there is potential generated between the earthed rod and the metallic enclosure of that device.
The circuitry inside the ELCB senses the potential difference and when this potential difference reached at 50volt then ELCB cuts off the main supply from the connected device. This way it ensures the safety of the human beings. To know the operation time of ELCB, lets see the following example. The safest limit of current which human body depends on multiple factors can withstand is 30mA sec.
The current flowing through body to the ground will be:. However, it is not used widely nowadays because of its some major disadvantages mentioned in the next section. Residual Current Breaker RCB works on the assumption that the current going to the electronics device must come out from the neutral wire, if there is no other way for current flow.
In simple words, RCB measures the current going inside the connected device and coming out from the device. If both of these current are equal, then there would no problem with the normal functionality of the device.
This device is more sensitive and accurate than ELCB and its functionality does not entirely depend on the earthed rode wire connection like voltage ELCB. The operating principles are same as above but it provide more and reliable operation with overload protection in single box. Here is the table in image for reference. Related Posts:. For Icu tested O-t-CO.
Save my name, email, and website in this browser for the next time I comment. Take an example of that outgoing red color wire accidentally have a contact with the green color wire, then there is a leakage of current flows between the phase wire and green ground wire.
Due to this, there is an voltage drop developed across the tripping coil. This voltage drop is enough to activate the trip circuit. Please enter your comment! Please enter your name here.
You have entered an incorrect email address! ELCB consist of coil is connected in series with the earth point. What is RCCB? RCCB stands for Residual Circuit Breaker, It is essentially a current sensing device used to protect a low voltage circuit in case of a fault. It contains some switch device that switches off whenever some fault occurs in the connected circuit. You may also learn about this topic:. Email This BlogThis! No comments:. Newer Post Older Post Home. Subscribe to: Post Comments Atom.
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