Switchgear is an electrical equipment that is used to monitor, control and protect electrical circuits and other devices. There are many types of control & switch gears classified based on numerous factors like current rating, interrupting rating, voltage class, insulation type, interrupting device, operating method, type of current, application and purpose. However, here we have explained the most commonly used Low voltage switchgear. Essentially consists of switching & protecting devices such as switches, fuses, isolators, circuit breakers, relays, control panels, lightning arrestors, current transformers, potential transformers, and various associated equipments. However, the functionality of all switch gear remains same:
They are widely used in power generating station, transformer & distribution substations, commercial and industrial buildings, refineries, paper mills, metal smelters and many other places where electric power is distributed to other machineries or equipments.
Low-voltage switchgears are basically used with equipments that operate at 1000 volts or less than that in order to protect the system from voltage or power fluctuations. These devices ensures electrical safety in industrial, commercial and utility installations involving generators, motors, feeder circuits and transmission & distribution lines.
For Low voltage applications, switchgears are used with circuit breaker in the form of thermal-magnetic devices or residual-current operated tripping devices to provide electrical protection. Based on type of such circuit breaker they have been classified into following categories:
MCB – Miniature circuit breaker is an electromagnetic device enclosed in a molded insulating material used for rated current not more than 100A. It is time delay tripping device in which the magnitude of over-current controls the operating time. Trip settings are not adjustable over here.
Function – Under normal conditions, it operate as a switch to make the circuit ON or OFF. Whereas under overload or short circuit scenario, it trips off the circuit and stop the current flow. Generally, these are designed to operate at less than 2.5 milliseconds during short circuit faults and 2 seconds to 2 minutes in case of overloads (depending on the level of current).
MCCB – Molded case circuit breaker is useful for both low-power and high-power applications, ranging from 15 ampere – 2500 ampere current rating. Additional advantage of MCCB as compared to MCB is that it comes with trip adjustment and they are much larger in size.
Function – It protects against overload by tripping the fault line, also in many cases when adequate manual switches are not fitted at that time it can act as a normal switch as well.
RCCB – A Residual Current Circuit
Breaker is a current sensing device used to protect a low voltage circuit in case of a leakage fault. It is essential protective device and a necessity in electrical safety for any house. It automatically switch off the power supply whenever the current leaks out and does not return back through neutral.
Function – If the current flowing in the equipment or live wire returns in a neutral wire with a different value, results into current leakage. Such leakages are called residual current which then RCCB detects and break the current supply. Even the slight difference between the live and neutral wires is detected by RCCB resulting to tripping off the power supply.
ACB – Air circuit breaker is used for low voltages, generally up to 15KV and rupturing capacities of 500MVA. Air Circuit breakers normally have two pairs of contacts. The main pair of contacts carries the current at normal load and these contacts are made of copper. The additional pair is the arcing contact and is made of carbon.
In order to get the finest quality range of low voltage switchgear, it is very much necessary to buy it only from authorized dealers. The product must have following properties:
We at our online electrical store i.e., Eleczo.com houses entire listing of low voltage switch gears manufactured by trusted brands like Schneider Electric, Havells, L&T Switchgear, Siemens, ABB, C&S Electric, etc. along with detail specification of individual product to make it easier for you to pick out the best match for your requirements. Quality products, tested components, wholesale price switch gears and many other discounts and offers all at our electrical zone.
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