Switched-mode power supply

A switched-mode power supply (switching-mode power supply, SMPS, or switcher) is an electronic power supply that incorporates a switching regulator to convert electrical power efficiently. Like other power supplies, an SMPS transfers power from a source, like mains power, to a load, such as a personal computer, while converting voltage and current characteristics.

 

 

SMPS

 

 

The electric energy is not normally used in the form in which it was produced or distributed. Practically all electronic systems require some form of energy conversion. A device that transfers electric energy from a given source to a given load using electronic circuits is referred to as power supply. Of course, it does not really supply power, it just converts it, so "converter" is a more accurate term for such a device.

 

 

Flow chart

 

Switching regulators are used as replacements for linear regulators when higher efficiency, smaller size or lighter weight are required. They are, however, more complicated; their switching currents can cause electrical noise problems if not carefully suppressed, and simple designs may have a poor power factor.

Miniature circuit breaker(MCB)

Miniature circuit breaker(MCB) can be defined as a automatically operated electrical switch designed for the purpose of protection of any electrical circuit from damage that can occur by overload or short circuit. Basic function of MCB is to detect a fault condition and to stop flow of electrical current. Contrary to a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.

Types of MCB

Depending upon our requirement and phase of current to be used we use various MCBs like 1 Pole,2 Pole, 3 Pole, 4 Pole

1 Pole MCB

 

2 Pole MCB

 

3 Pole MCB

 

4 Pole MCB



MCB (Miniature Circuit Breaker)—rated current not more than 100 A. Trip characteristics normally not adjustable. Thermal or thermal-magnetic operation. Breakers illustrated above are in this category.

There are three main types of MCBs:

1. Type B - trips between 3 and 5 times full load current

2. Type C - trips between 5 and 10 times full load current

3. Type D - trips between 10 and 20 times full load current


The miniature circuit breaker (MCB) plays an important role in providing overcurrent protection and a disconnect means in electrical networks.


The Magnetic trip unit protects against a short circuit. The magnetic trip unit is comprised of an electromagnet and an armature.