Get Knowledge About Switchgear
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Switchgear is the combination of electrical components used for switching, protecting, and controlling electrical systems. It contains components like switches, circuit breakers, fuses, and relays. Switchgear serves three main functions: providing electrical protection, isolation, and control. It allows circuits to be switched on or off during normal operation and detects and disconnects faulty sections when abnormalities occur. Switchgear comes in low, medium, and high voltage varieties and must operate reliably, discriminate accurately, act quickly, support manual and instrument control.
Get Knowledge About Switchgear
- 1. What is Switchgear and itsWhat is Switchgear and its components?components?
- 2. What is the purpose ofWhat is the purpose of Switchgear?Switchgear? The apparatus used for switching, controlling and protecting the electrical circuits and equipment is known as switchgear. Switchgear power systems are often enclosed in houses and buildings if there are low voltage levels. For an area with high voltage levels the switchgear power system may be located outdoors. Switchgear power systems are the combination of electrical disconnects that serve the function of isolating electrical equipment. Three basic functions of switchgear power systems are: (1) Electrical Protection. (2) Electrical Isolation. (3) Control.
- 3. Components of SwitchgearComponents of Switchgear A switchgear essentially consists of switching and protecting devices such as switches, fuses, isolators, circuit breakers, relays, control panels, lightning arrestors, current transformers, potential transformers, and various associated equipments. These swithgears are designed to operate under both normal and abnormal conditions. During normal operationDuring normal operation switchgear permits to switch on or off generators, transmission lines, distributors and other electrical equipment. During Abnormal ConditionDuring Abnormal Condition when a failure (e.g. short circuit) occurs on any part of power system, a heavy current flows through the equipment, threatening damage to the equipment and interruption of service to the customers. However, the switchgear detects the fault and disconnects the unhealthy section from the system.
- 4. Essential Features of SwitchgearEssential Features of Switchgear (I) COMPLETE RELIABILITY(I) COMPLETE RELIABILITY When fault occurs on any part of the power system, the switchgear must operate to isolate the faulty section from the remainder circuit. (II) ABSOLUTELY CERTAIN DISCRIMINATION(II) ABSOLUTELY CERTAIN DISCRIMINATION When fault occurs on any section of the power system, the switchgear must be able to discriminate between the faulty section and the healthy section. It should isolate the faulty section from the system without affecting the healthy section. This will ensure continuity of supply. (III) QUICK OPERATION(III) QUICK OPERATION When fault occurs on any part of the power system, the switchgear must operate quickly so that no damage is done to generators, transformers and other equipment by the short-circuit currents. If fault is not cleared by switchgear quickly, it is likely to spread into healthy parts, thus endangering complete shutdown of the system.
- 5. (IV) PROVISION FOR MANUAL CONTROL(IV) PROVISION FOR MANUAL CONTROL A switchgear must have provision for manual control. In case the electrical (or electronics) control fails, the necessary operation can be carried out through manual control. (V) PROVISION FOR INSTRUMENTS(V) PROVISION FOR INSTRUMENTS There must be provision for instruments which may be required. These may be in the form of ammeter or voltmeter on the unit itself or the necessary current and voltage transformers for connecting to the main switchboard or a separate instrument panel.
- 6. Classification of SwitchgearClassification of Switchgear Switchgear can be classified on the basis of voltage level in to the following : (1) Low voltage (LV) Switchgear :(1) Low voltage (LV) Switchgear : Generally electrical switchgear rated upto 1KV is termed as low voltage switchgear. The term LV Switchgear includes low voltage circuit breakers, switches, off load electrical isolators, HRC fuses, earth leakage circuit breaker, miniature circuit breakers (MCB) and molded case circuit breakers (MCCB) etc i.e. all the accessories required to protect the LV system.
- 7. (2) Medium voltage (MV) Switchgear :(2) Medium voltage (MV) Switchgear : From 3 KV to 36 KV switchgear system is categorized as medium voltage switchgear or MV switchgear. These switchgears are of many types. They may metal enclosed indoor type, metal enclosed outdoor type, outdoor type without metal enclosure, etc. (3)(3) HighHigh voltage (HV) Switchgear :voltage (HV) Switchgear : The power system deals with voltage above 36KV, is referred as high voltage switchgear. As the voltage level is high the arcing produced during switching operation is also very high. So, special care is to be taken during designing of high voltage switchgear. High voltage circuit breaker, is the main component of HV switchgear, hence high voltage circuit beaker (CB) should have special features for safe and reliable operation. Faulty tripping and switching operation of high voltage circuit are very rare. Most of the time these circuit breakers remain, at ON condition, and may be operated after a long period of time. So CBs must be reliable enough to ensure safe operation, as when required. High voltage circuit breaker technology has changed radically in the last 15 years.
- 8. Address : Lake Shore Electric Corporation,Address : Lake Shore Electric Corporation, 205 Willis Street205 Willis Street Bedford, OH 44146Bedford, OH 44146 Phone : 800 225 0141Phone : 800 225 0141 Website :Website : http://lake-shore-electric.com/http://lake-shore-electric.com/