RESIDENTIAL ELECTRICAL DEVICES

Residential Electrical Devices

All electrical installations must be designed, constructed and maintained to provide protection against the following.

1.       Overload

2.       Short circuits ( phase to phase or phase to neutral or phase to earth)

3.       Electrical shock (due to Direct or Indirect contact with electricity)

Miniature Circuit Breaker (MCB)

Miniature Circuit Breaker is a protection device. A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit.

Circuit breakers are made in varying sizes, from small devices that protect an individual household appliance up to large switchgear designed to protect high voltage circuits feeding an entire city.

Miniature Circuit Breaker (MCB) or Low-voltage circuit breakers, less than 1,000 V_AC, rated current not more than 100 A types are common in domestic, commercial and industrial application. Tripping characteristics are normally not adjustable. It can be thermal or thermal-magnetic operation.

The commonly-available preferred values for the rated current are 3A, 6 A, 10 A, 13 A, 16 A, 20 A, 25 A, 32 A, 40 A, 50 A, 63 A, 80 A and 100 A. also available in single pole, double pole and three pole.

Single Pole - Double Pole - Three Pole - four Pole

Moulded Case Circuit Breaker (MCCB)

MCCBs have a higher fault current interrupting capacity than MCB. An MCCB comes with an adjustable trip characteristic for the higher models. Usually, this type of circuit breaker would provide amps as high as 2,500 or as low as 10 depending on what is necessary. Their interrupting rating can be around 10,000 amps to 200,000 amps. The MCCB is more suited in providing energy for high-power equipment.

Moulded Case Circuit Breaker (MCCB)

For convenience’s sake, some MCCB units have electrical motor operators which means that they can be tripped using only a remote control. For industrial or commercial use, they may be utilized as standby power that runs on an automatic transfer switch.

Circuit breakers are installed in any structure that requires power for safety reasons. They are made to ensure that fire hazards or electrical problems would not occur in a home by cutting of electricity flow. This is usually done when the system experiences a “short circuit” or an “overload.” Circuit breakers are usually reset after they have been “tripped.” 

Residual-Current Device (RCD), Or Residual-Current Circuit Breaker (RCCB)

An RCD, or residual current device, is a life-saving device which is designed to prevent you from getting a fatal electric shock if you touch something live, such as a bare wire. It can also provide some protection against electrical fires.

A RCD or RCCB is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor. Such an imbalance may indicate current leakage through the body of a person who is grounded and accidentally touching the energized part of the circuit. A lethal shock can result from these conditions. RCCBs are designed to disconnect quickly enough to prevent injury caused by such shocks. They are not intended to provide protection against over current (overload) or all short-circuit conditions.

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