Before I introduce delixi MCB and lightening Arrestors. I would like to explain what MCBs and surge protectors are simple terms.MCB stands for a miniature circuit breaker. As the name implies, an MCB is an electrical device or component that breaks the circuit. It can break a circuit either intentionally or forced due to a short circuit. Intentionally when you switch the circuit breaker to isolate a bulb or any machine that is connected in that circuit.
A circuit breaker is designed to interrupt power to a complete circuit when there is an overload in that circuit. This is done to protect electrical and electronic appliances that can be damaged due to overloads and surge.
It is good to say that when I mention the word circuit. I am referring to circuits in your home. Like lighting, power or socket outlets, air conditioners geyser and many others.
A lightning arrestor is an electrical device that protects appliances and machines. It does this by diverting excess currents and voltages to the ground.
Therefore, it is important to have a very good earth network when wiring or installing electrical machines.
Why delixi MCB and arrestors
As I have already said, MCBs and lightning arrestors, protect both people and appliances. From electrical shocks and damaging your valuable electrical appliances and machines.
Delixi electric is the largest joint venture in China. As a result, delixi is a leading brand in the electrical industry. Delixi electric MCB is widely used in big projects. Like in.
- Power generation and distribution
Delixi products are the best in all the classes of research and adhering to international standards. As a result of this, you have circuit breakers that are designed to last for a longer period of time. Before you can replace them. All delixi products pass through the same quality tests as its partner Schneider electric. When you use delixi products, you are using Schneider products. Schneider delixi partnership has been around since 2007.
Here is a video of the delixi group.
Types of MCB’S
They are basically three main types of MCBs.These are B, C and D.The type of MCB is mainly determined by the level of a magnetic strip of the circuit breaker. Circuit breakers will protect equipment and people mainly by using, Overload protection and magnetic fault protection. Overload protection: This feature of a circuit breaker, prevents accidental overloading in a load fault situation. Magnetic fault protection, this feature of MCB’s operates when the fault reaches a predetermined level and trips the MCB within one-tenth of a second.
Short circuit rating: This rating is intended to protect against heavy faults in thousands of amperes. The ability of a circuit breaker to operate under these conditions gives its short circuit rating. In kilo amperes(KA).For domestic applications, 6KA is adequate whereas, for commercial and industrial applications,10KA and above short circuit rating is required.
|MCB Type||Tripping time||Operating time|
|B||3 to 5 times full load current||0.04 to 13 seconds|
|C||5 to 10 times full load current||0.04 to 5 seconds|
|D||10 to 20 times full load current||0.04 to 3 seconds|
B type MCB
Mainly suitable for domestic applications and resistive loads.
C type MCB
D type MCB.
Suitable for protection of cables and high inductive loads with high starting currents.Like:
- Large battery charging systems
- X-ray machines
- UPS systems
- Industrial welding equipment
- Large winding motors.
The basic requirement for protection.
Here when I refer to the basic requirements, I mean the protection of power systems. A well-protected power system must provide protection as listed below.
- To ensure the safety of personnel
- Safeguard the entire power system
- To ensure continuity of supply
- Reduce the cost of repair works.
In order for a power system to achieve the above-projected outcomes, it must have the following qualities.
- RELIABILITY: This ensures that the power system will operate in a predetermined manner when an electrical fault is detected.
- SELECTIVITY: It is put as a part of a power system to detect faults and isolate faulty parts of the system.
- STABILITY: This ensures that all healthy circuits are intact and undisturbed to ensure continuity of supply.
- SENSITIVITY: To detect even the smallest value of fault current or system abnormalities and operate correctly at it’s pre-set settings.
- SPEED: To operate speedily when it is required thereby minimizing damage and ensuring safety to personal.
Electrical faults are usually disturbances that disrupt the smooth running of electrical power systems. What causes electrical faults? Most of the time, electrical faults happen due to the breakdown of the insulating material between live conductors or between live conductors and earth.
What causes the break down of insulating material?
The break down in the insulating materials can be caused by one or several factors listed below.
- Mechanical damage
- Voltage surge(usually caused by lightning or switching)
- Ionization of air
- Deteriorating of insulating material. either due to unfavorable environments, old age and misuse of equipment.
Terms related to power systems protection.
- SURGE: A sub-cycle voltage waveform in an electric circuit, which is evidenced by a sharp brief disturbance of the input power voltage waveform.
- HARMONICS: This is the mathematical representation of the distortion of a pure sine wave.
- INTERRUPTION(OUTAGE): The complete loss of voltage for a time period between a half-cycle and two seconds.
- NOISE DISTURBANCE: Electrical noise is unwanted electrical signals that produce undesirable effects in the circuits of sensitive electronic equipment. (these are neutral to ground impulses or transient surge)
- TRANSIENT FAULT: This is the fault that does not damage the insulation permanently and allows the circuit to be safely re-energized after a short period of time.
- PERMANENT FAULT: This is the permanent damage made to insulating material of either transmitting material or associated equipment connected.
What is a protective relay?
A protective relay is a device that operates to disconnect a faulty part of the system. In this manner, it protects the remainder of the system from further damage.
A fuse is probably the oldest form of a protective device. I think that a fuse is a simplest and straight forward protective device to use. How does a fuse operate? when excessive current passes through the element of a fuse, it produces thermal energy. as a result of the energy produced by the excess energy, the fuse element melts hence, protecting the device connected in that circuit.
Things to know on fuses.
Some years back I used to think that when a fuse is rated at 13A, it will automatically trip when a 15A current passes through it. I know a lot of people still think that a fuse will blow immediately the rated current is exceeded by a few amperes. But the truth is that a fuse has a typical inverse time characteristic. This entails that a pick-up value for the fuse will start to operate at twice the rated value of the fuse. It should be noted that the higher the current, the faster the fuse will blow.
- A fuse will only detect a fault associated with the excess current.
- Fuses will only blow in the earth’s fault condition once the current in the faulty phase has increased beyond the overcurrent value.
- fuses don’t offer adequate earth fault protection.
- a fuse can not be given an external command to trip
- A fuse should be replaced after every operation.
should you have any questions on this topic, feel free to do so in the comments section below.