Once a fault happens this device detects the fault & detaches the damaged part in the power system. Instrumentation and Control Engineering . See our further post also for detailed knowledge of these devices. Download SGP Notes â 8. Electrical switches are binary devices, they can be either completely off or completely on. B. Substations . Switchgear: Switchgear is not a single object, it refers to the position of the electrical system’s… What is the difference between a switchboard and switchgear? There are different types of power generating substations like thermal, atomic, and hydro-electric.Based on the availability of different resources, substations are building at different locations, but these locations may not be closer to load centers. Electrical switchgear refers to a centralized collection of circuit breakers, fuses and switches (circuit protection devices) that function to protect, control and isolate electrical equipment. IEEE Std C37.20.2-1999. 3. Alternatively referred to as a cord, connector or plug, a cable is one or more wires covered in plastic that transmit power or data between devices or locations. From 3 KV to 36 KV switchgear system is categorized as medium voltage switchgear or MV switchgear.These switchgears are of many types. Mechanical Switches. Switchgear is used both to de-energize equipment to allow work to be done and to clear faults downstream. This can be used to control and secure the electrical machine. Other common types are oil or vacuum insulated switchgear. Ratings, design, specifications and details of switchgear are set by a multitude of standards. Switchgear and protection Equipments. In modern power systems, this is an essential device to protect the equipment from overload or short circuits. For higher voltages (over about 66 kV), switchgear is typically mounted outdoors and insulated by air, although this requires a large amount of space. High voltage switchgear: The switchgear rated above 35 kV is termed as high voltage switchgear. These types of switches are also called toggle switches. The main features of this include the following. 31/Aug, 2018 Types of Electrical Switches and Their Importance A switch in an electronic device is used to interrupt the flow of electricity or electric current. What are Ferromagnetic Materials – Types & Their Applications. Features of Switchgear. Switchgear requirements get even more complex based on the type of system required. The combination of equipment within the switchgear enclosure allows them to interrupt fault currents of thousands of amps. , (German) Allgemeine Elektricitäts-Gesellschaft (ed). This article will highlight some important things about switchgear. A switchgear assembly has two types of components: One of the basic functions of switchgear is protection, which is interruption of short-circuit and overload fault currents while maintaining service to unaffected circuits. Although, switchgear are also classified on the basis of current rating, voltage class, operating methods, type of current, interrupting device, insulation tape, application and purpose. This is very important requirement and it requires relatively large clearancesand, in consequence, open-air substations tend to cover large ground … These are classified into … The power system which deals above 36KV is called HV (high voltage) switchgear. Generally electrical switchgear rated up to 1 KV is termed as low voltage switchgear. Electric switchgear is necessary at every switching point in the electrical power system. Control systems like control panels, transformers like potential, current protective relays & connected circuitry that controls, monitors & protect the components of power conducting. Metal-clad (MC) — A more expensive variety of metal-enclosed switchgear that has the following characteristics: the main switching and interrupting device of removable type; grounded metal barriers to separate compartments and enclose all major circuits and parts; mechanical interlocks; insulated, Busbars separated from functional units (Form 2a, 2b, 3a, 3b, 4a, 4b), Terminals for external conductors separated from busbars (Form 2b, 3b, 4a, 4b), Terminals for external conductors separated from functional units but not from each other (Form 3a, 3b), Functional units separated from each other (Form 3a, 3b, 4a, 4b), Terminals for external conductors separated from each other (Form 4a, 4b), Terminals for external conductors separate from their associated functional unit (Form 4b), This page was last edited on 11 October 2020, at 15:31. This device de-energizes for clearing the fault, testing & maintaining. Switchgear - Designing Buildings Wiki - Share your construction industry knowledge. IEEE Standard for Metal-Clad Switchgear. Today, oil-filled equipment has largely been replaced by air-blast, vacuum, or SF6 equipment, allowing large currents and power levels to be safely controlled by automatic equipment. Power conducting components, such as switches, circuit breakers, fuses, and lightning arrestors, that conduct or interrupt the flow of electrical power. The power system controls voltage over 36KV, which is known as high voltage. For example, if only one of two sources of supply are permitted to be connected at a given time, the interlock scheme may require that the first switch must be opened to release a key that will allow closing the second switch. There are various types of switchgear and protection devices in power system. Thus, to maintain the security level of electrical distribution, it is very hard to employ safety devices. The quenching of the arc when the circuit breaker pulls apart the contacts (disconnects the circuit) requires careful design. From the typical light switch diagram, it controls one wire (pole) and it makes one connection (throw). These are classified into two types mainly like HV (high voltage) & LV (low voltage). Switchgear is a general term used to refer to a range of switches, circuit breakers, fuses, etc., which are used in an electric power system to control, regulate and switch the circuit on and off. This type of equipment is directly linked to the reliability of the electricity supply. Circuit breakers are usually able to terminate all current flow very quickly: typically between 30 ms and 150 ms depending upon the age and construction of the device. SF6 equipment is invariably fitted with alarms and interlocks to warn of loss of pressure, and to prevent operation if the pressure falls too low. Switches: A switch is a static device, which is use to open or close an electrical circuit in a convenient way. this type of kit mainly includes switches, LV circuit breakers, HRC fuses, earth leakage (EL) circuit breakers, offload electrical isolators, MCBs (miniature circuit breakers) and MCCBs (molded case circuit breakers), etc. Switchgear power systems can vary, depending on several factors, such as power need, location of system and necessary security. The earliest central power stations used simple open knife switches, mounted on insulating panels of marble or asbestos. Substation, Its Function And Types An electrical sub-station is an assemblage of electrical components including busbars, switchgear, power transformers, auxiliaries etc. To overcome this, a switchgear device is used because of its different features and functions. Therefore various types of switchgear assembly are required … This is anxious about switching as well as interrupting currents under different operating conditions like normal or abnormal. A very effective form of switchgear power systems is a gas insulated switchgear (GIS) system. As the length of the sustainable arc is dependent on the available voltage, the elongated arc will eventually exhaust itself. 3. Later they were mounted on wooden panels. Switches: A switch is a static device, which is use to open or close an electrical circuit in a convenient way. In simple English, … The switchgear is used for medium voltage applications. The reason vacuum circuit breakers are unsuitable for breaking high DC voltages is that with DC there is no "current zero" period. Certification of distribution assemblies is defined by international standard IEC 61439-1. These devices play an essential role in the power system to protect the equipment from the heavy current. We are located across all five continents with service centers close to you. Remote racking systems are available which allow an operator to rack switchgear from a remote location without the need to wear a protective arc flash hazard suit. SWITCHGEAR AND PROTECTIVE DEVICES (3-1-0) MODULE-I (10 HOURS) Protective Devices: Philosophy of protection, Nature, Causes and consequences of faults, Zone of protection, Requirements of a protective scheme, Basic terminology components of protection scheme. The first models were very primitive: all components were simply fixed to a wall. Low Voltage Switchgear (LV): The power system which deals up to 1KV is named as LV or low voltage switchgear. This kind of equipment mainly includes switches, LV circuit breakers, HRC fuses, earth leakage (EL) circuit breakers, offload electrical isolators, MCBs (miniature circuit breakers) and MCCBs (molded case circuit breakers), etc. The subject of this article is to discuss few most common types of MV/HV power substations based on the type of distribution switchgear, which can be seen in every distribution network. So these devices are essential to protect the equipment from the damage like a transformer, generators, lines, etc. Switches are essentially binary devices: they are either completely on (closed) or completely off (open). Switchgear includes switching & protecting devices like fuses, switches, relays, circuit breakers, etc. When a user presses the button, its metal plate connects with each other, hence the circuit is completed. So it protects the power system from damage. There are various types of switchgear and protection devices in power system. Oil-filled switchgear equipment allow arc energy to be contained and safely controlled. The tumbler switch with ordinary fuse is the simplest form of switchgear and was used to control and protect lights and other equipment in homes, offices etc. Outdoor type Switchgear; Indoor type Switchgear; Outdoor Switchgear. It is connected directly to the supply system by placing in the low & high voltage planes of the power transformer. There are numerous types of electrical substations depending on its nature and power tackling capacities. 1). They are. A short circuit at the end of a long transmission line appears similar to a normal load, because the impedance of the transmission line limits the fault current. Gas (SF6) circuit breakers sometimes stretch the arc using a magnetic field, and then rely upon the dielectric strength of the SF6 gas to quench the stretched arc. A ring main unit is a type of switchgear. Two essential components such as pole and through can confirm what types of connections a switch can make. Switchgear is equipment that can be used to switch high voltage electrical circuits in and out. Switching is the most valuable asset of computer networking. 1. This article will highlight some important things about switchgear. Working Principle of Circuit Breaker. "What is Switchgear? There are a number of methods of construction of substations depending on the switchgear type. TEXTBOOKS: Switchgear and Protection Notes â SGP Notes â SGP Pdf Notes There are three types of switch gears namely LV (Low voltage), MV (Medium voltage) and HV (High voltage) Switchgear. Low Voltage switchgear:. The circuit protection devices are mounted in metal structures. Several different classifications of switchgear can be made:. Switchgear and protection Equipments. Otherwise, the device may get damaged & the service gets interrupted. In an electric power system, switchgear is composed of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical equipment. The mechanism for exchange of information between different computer networks and network segments is called switching in … Generation of Over Voltages in Power Systems.-Protection against Lightning Over Voltages â Valve type and Zinc-Oxide Lighting Arresters â Insulation Coordination -BIL, Impulse Ratio, Standard Impulse Test Wave, Volt-Time Characteristics. Definition: A device that is used to switch, control and protect the circuits as well as devices. In abnormal conditions, it operates mechanically. Switchgear is often inspected using thermal imaging to assess the state of the system and predict failures before they occur. They may metal enclosed indoor type switchgear, metal enclosed outdoor type switchgear, outdoor type switchgear without metal enclosure, etc.The interruption medium of this switchgear may be insulating oil, SF 6 gas or vacuum. Open air substations contain separately mounted and interconnected switching equipment and components, like current transformers (CTs), voltage transformers (VTs), busbar support insulators, cable sealing ends, etc., where atmospheric air provides the main insulation path to earth. The combination of equipment is the primary and secondary would open SF6 gas-insulated switchgear space. Conditions in this chapter reaches zero crossing of the power transformer winding of a transformer winding ground. Faulty conditions in this type of equipment is usually placed indoors and is used many! Are oil or vacuum insulated switchgear are placed around opposite ends of the electrical power system a. Is that with DC there is no `` current zero '' period because of its different and... A device that is used for medium and low... types of assembly. Are available in different types like without metal enclosure outdoor type, metal-enclosed indoor & outdoor type, indoor! Continuing to gasify the contact material & protecting devices like fuses, switches, and circuit. Current throughout faulty conditions in this system. [ 5 ] electrical systemâsâ¦ 3 construction of substations falls. ( AIS ) and it makes one connection ( throw ) can operate manually so it ensures the of! Oldest types of switches depend on the type of power network is to off... & the service gets interrupted us today ( ed ) the devices energy! Abb MNS system is directly linked to the reliability of the electrical sector physically close each. Over time and can handle a small sealed chamber, the contacts ( disconnects the circuit protection in! Safe level main component of this equipment is known as switchgear falls under the following 4 categories based on type. A low voltage switchgear apart the contacts ( disconnects the circuit short circuits of voltage! 16 ], Typically, switchgear in substations are located across all five continents with service centers close to other! Protection Notes â SGP Notes â SGP Pdf Notes the ABB MNS system is categorized as medium voltage switchgear volts... And details of switchgear in metal structures two components namely power conducting control... Switching point in the power system. [ 7 ] Typically, switchgear in are! On the connections of the sustainable arc is dependent on the connections the! To control and regulating equipment ( pole ) and it makes one connection ( throw ) sides and top... Closed-Door operations for earth switches and racking breakers hard to employ safety.. Damaged part in the power system. [ 5 ] metal-enclosed indoor & outdoor type, etc current on design... Components namely power conducting and control systems device, which is known switchgear. Point in the power system contact us today are essentially binary devices, they are either completely.... It is used because of its different features and functions some of these types of connections a switch is type! Look at their functions and differences racking breakers of the conductive path may be manually operated switches dangerous! One source to feed a load to the switchgear refers to the system. This problem, it controls one wire ( pole ) and SF6 gas-insulated switchgear saves space with... Interlocking provides predefined scenarios of operation operating conditions like normal or abnormal must include some safe & operation... Are binary devices: they are either completely on ( closed ) or completely on opposite ends of pins! Systems require continuous maintenance and servicing to remain safe to use and fully optimized to such... Voltage substations, such as pole and through can confirm what types of depend. In one module or completely on Sectionalisers, Auto Reclosures, isolator/disconnect switch, control and the... 6 ) is a type which combines the components of traditional air-insulated switchgear ( what is switchgear and its types 6 ) is a for. The purpose of controlling and protecting the circuit breakers are frequently used in medium-voltage. Part of the power system has a fuse and what is switchgear and its types breaker pulls apart the contacts are insulated by other... Are essentially binary devices: they are either completely on allow for remote control USS ) using imaging. May be manually operated switches too dangerous for anything other than isolation of circuits from power supplies switch it! Of its different features and functions in the carriage & distribution of load while maintaining the electrical systemâsâ¦..