The apparatus used for controlling, regulating and switching on or off the electrical circuit in the electrical power system is known as switchgear. A wide variety of ht switchgear options are available to you, there are 60 suppliers who sells ht switchgear on, mainly located in asia. Each breaker shall be provided with an emergency manual trip, mechanical. Major inspection should be scheduled for power plant shutdowns and concentrate for low voltage. Rao, switch gear and protection, khanna publication. In an electric power system, switchgear is the combination of electrical disconnect switches, fuses or circuit breakers used to control, protect. Ht lt switchgear service written by administrator sunday, february 2011 14. Inspection, test and measurement procedures for lv and mv. In an electric power system, switchgear is composed of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical. Switchgear, electrical switchgear, medium voltage switch.
We are all familiar with low voltage switches and rewirable fuses in our. It applies to enclosure of electrical equipments with a rated voltage of less then or equal to 72. This video provides all the important concept of switchgear and protection of power system in detail and also provides some important points to remember for exams and interviews. Thus switchgear can be taken as a general term covering a wide range of equipment concerned with the switching, protection, and control of various electrical equipment. The handbook of switchgears offers electrical power engineers and technicians a onestop guide to the basic design, operation, and protection of switchgears. Switchgear can be a device or equipment that is used to safely connect, operate, protect and disconnect an electrical circuit within set rated limits of voltage and current. Inspection, test and measurement procedures for lv and mv up.
Switchgear and protection we are all familiar with low voltage switches and rewirable fuses in our home. Circuit breakers provide a manual means of energizing and deenergizing a. Handbook of switchgears mcgrawhill education access. The protection index is the level of protection provided to by an enclosure against access to hazardous parts, the penetration of solid foreign bodies and of water. As such switchgear can be a power fuse or a power breaker or a combinatio. The enclosure exterior shall be painted with polyurethene paint powder coated and tropicalized to indian weather conditions. Voltage more than 33kv but less than or equal to 230kv is termed as hv ht. Voltage more than 650v but less than or equal to 33kv is mv mt. Copy of nit 02 pages instruction to bidders 03 pages general conditions of contract 01 book special conditions of contract 07 pages safety, health and environment guide lines for contractors 30 pages. The switchgear on the lowvoltage side of the transformers may be located in a building, with mediumvoltage circuit breakers for distribution circuits, along with metering, control, and protection equipment. The function of a switchgear switchgear has to perform the functions of carrying, making and breaking the normal load current like a switch. Fundamentals of electrical substations and switchgear. This subject provides the knowledge on switchgear and protection of various power system elements. Sep 17, 20 distance protection whenever overcurrent relay is not selective or circuit requirements change, then distance protection is preferred.
The entire range of havells industrial switchgear include switches, circuit breakers and conventional devices that are designed and manufactured according to world class standards. Home category electrical engineering mcq questions and answers switchgear and protection. In other words systems used for switching, controlling and protecting the electrical power. Maintenance of electrical switchgear ms28, tl4 11 chapter 1 introduction 110 purpose 111 scope this handbook contains information on safety practices and environmental considerations when working on switchgear, descriptions of typical classes of switchgear, and preventive and corrective maintenance guidelines for switchgear. The ip code is a coding system to indicate protection index. A switchgear is a generic term which includes all the switching devices associated with power system protection. So to protect the lines, generators, transformers and other electrical equipment from damage automatic protective devices or switchgear devices are required. Types of circuit breakers air blast, air break, oil, sf6 and vacuum circuit breakers. Vacuum interrupters design applications and limitations. We have brought together the combined experience of. Relay is a sensing device which senses abnormal voltage and current conditions in power system and sends signal to circuit breaker to remove faulty part from rest of the power system. To study different relays characteristics to understand the method of circuit breaking, arcing phenomena. In india, voltage less than or equal to v is termed as lv lt.
Switchgear and protective devices 2015 3 p a g e syllabus switchgear and protective devices 310 modulei 10 hours protective devices. Ht switchgears manufacturer, lt switchgears supplier. Ht switchgear february 4, 2017 by tnsadmin ht switchgear lbs substation leave a comment key featurestechnical datadownload application one of the basic functions of switchgear is protection, which is interruption of shortcircuit and overload fault currents while maintaining service to. Relay is a sensing device which senses abnormal voltage and current conditions in power system and sends signal to circuit breaker to remove faulty part. The insulationresistance shall be taken with all the winding earthed, expect, the one being tested. When a fault occurs within the boundary of a particular zone, then the protection system responsible for the protection of the zone acts to isolate by tripping the circuit breakers every equipment within that zone from the rest of the system. Electrical distribution needs are continuously evolving in residential, commercial and industrial sectors. Back up protection operates only when primary protection has failed. Ms28 handbook maintenance of electrical switchgear tl4.
Switchgear and protection electrical engineering mcq questions and answers. The apparatus used for switching, controlling and protecting the electrical circuits and equipment is known as switchgear. Problem with over current relaying is that fault current depends upon ckt condition and generating capacity. Industrial switchgear, circuit breakers, switches havells india. Vcb panels are precisely designed following strict industry parameters and are appreciated for features like superior quality and cost effectiveness. Abbs ecoefficient airplus technology delivered to norwegian smart grid. A grid providing ventilation and a protective cover for a manhole opening. Ht switchgear february 4, 2017 by tnsadmin ht switchgear lbs substation leave a comment key featurestechnical datadownload application one of the basic functions of switchgear is protection, which is interruption of shortcircuit and overload fault currents while maintaining service to unaffected circuits. For a short time it can withstand maximum c and iso. Chander, power system protection and switchgear, wiley eastern ltd. It also includes all devices associated with control, metering and regulating of electrical power systems.
Download switchgear and protection auroras engineering college. Improved operational safety, continuity of service, greater convenience and operating cost have assumed a tremendous significance. Mar 25, 2017 this video provides all the important concept of switchgear and protection of power system in detail and also provides some important points to remember for exams and interviews. The switch is used to manually open and close the electrical circuit in our home and electrical fuse is used to protect our household electrical circuit from over current and short circuit faults.
If these conditions changes, then overall protection needs to be changed. Ms28 handbook maintenance of electrical switchgear tl4, may. The switches, fuses, circuit breaker, isolator, relays, current and potential transformer, indicating instrument, lightning arresters and control panels are examples of the switchgear devices. Types of lighting arrestors are horn gap, expulsion type, gapless metal oxide type etc. External lighting protection l fire protection systems l comunication systems. While checking the value, external line, cable and lighting arresters shall be isolated from the h. It applies to enclosure of electrical equipments with a. Its products and solutions cater to industries, utilities, infrastructure, building and agriculture segments. This transformer is normally used for earth fault protection for low and medium. Abb ability digital switchgear solution ensures reliable power in helsinkis smart city district. Jan 27, 2018 switchgear can be a device or equipment that is used to safely connect, operate, protect and disconnect an electrical circuit within set rated limits of voltage and current. Annual overhauling of htlt switchgears and htlt motors.
A tough and resilient sheath with excellent fire resisting qualities. Ht switchboards hvx is the latest range of vacuum circuit breakers. Annual overhauling of htlt switchgears and htlt motors of. The term switchgear is a generic term that includes a wide range of switching devices like circuit breakers, switches, switch fuse units, offload isolators, hrc fuses, contactors, miniature circuit breakers, elcbs, gfcis etc. Installed in clean, well ventilated or airconditioned locations, switchgear will require little routine maintenance.
Electrical control panel, ht panels, lt panels, capacitor. Chander, power system protection and switchgear, wiley. A guide for ht and lt switchgear used in thermal power plant. Electrical machines and power transmission engineering course educational objectives. Medium voltage products technical guide protection criteria.
Sunil s rao, switchgear protection and power systems, khanna publishers, new delhi, 11 th edition reprint 3 rd edition, 2008 references. A combination of disconnect switches and breakers used to isolate equipment in substations. Switchgear, electrical switchgear, medium voltage switch gear. Mahesh engineering services, since 1974, is a professionally managed trading company involved in industrial electrical materials. For industrial applications, a transformer and switchgear lineup may be combined in one housing, called a unitized substation uss. To discuss the need for the protection and various protection schemes. It offers proven stateoftheart design to meet to specification for power switching devices in airinsulated switchgear upto 36 kv. Medium voltage products technical guide protection. Complete protection against most forms of electrolytic and chemicalcorrosion.
In other words systems used for switching, controlling and. Switchgear and protection electrical engineering mcq questions and answers home category electrical engineering mcq questions and answers switchgear and protection 1 in the following figure, which component ensures the safety of the line from damage. Relay and switchgear protection linkedin slideshare. Philosophy of protection, nature, causes and consequences of faults, zone of. Abb unveils abb ability digital switchgear for secondary distribution networks. The top countries of suppliers are india, china, and india, from which the percentage of ht switchgear supply is 6%, 91%, and 6% respectively. Abb delivers state of the art technologies to italys most innovative data center. Ht vcb control panels medium voltage panels exporter. System for ht lt connection hvpn supply go switch ht metering vcb. It refers to electrical equipment that regulates the flow of electricity within an electrical system. Aug 24, 2017 switchgear is the combination of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical equipment from the abnormal condition is called switchgear. The skid mounted substation shall be of modular construction housed in a single enclosure consisting of ht control panel with one number load break switch, one number vcb and all other metering and protection, one no 11kv415v dry type.
Commissioning of ht electrical system photo credit. First line of defense is provide by the back up relaying equipment. Cts and pts and their applications in protection schemes. These products are used to provide protection in the form of interruption of shortcircuit and overload fault currents, while maintaining service to unaffected circuits. Feb 26, 2017 in india, voltage less than or equal to v is termed as lv lt.
1135 1354 388 981 1547 465 1116 1376 1111 1351 1344 1043 835 909 265 328 765 1470 30 810 856 1171 413 625 406 1391 128 859 561 988 20 772 399 450 1234