Dear All, Welcome to the course of understanding schematics of “Transformer Protection Panel Schematics”. This course covers complete schematics of 20/26MVA 132/11 kV transformer protection panel. Trainer have over 18 years of field experience and has worked at 11/132/220/500kVSubstation, 1263MWpower plant, 660kVHVDCsystem. worked with several companies, SIEMENS, ABB, GE, SEC, KE, WAPDA, NTDC, ARAMCO, SABIC, MARAFIQ. Trainer has given hundreds of trainings online and offline, so it will be great to join this training and take advantage of field experience. This training is designed over as schematics, that will also be available to download. Topics covered in this training are as follows, Introduction to title pageHow page is divided in rows and columnsHow to track inter panel loopsDrawing Revision No, PhilosophyDrawing approval stages Why two ratings of transformer are mentioned on drawingsUnderstanding Drawing numberHow Bay numbers are assignedHow to define address of object at the pageHow to read list of contentOrdering code, Origin, Make of itemsDetails provided in GAdrawings Color coding, wire size, relay types, alarm, annunciation details, why GA drawing are important during design and commissioning stage / Maintenace stageGenerally, control wiring is grey, CTVTwiring RYB, trip ferrule in red color etc. Understand symbols & legendsSymbol of CT, VT, Relays, Aux, push button, Load break switch, power contact of CB, limit switch etcRelay and metering diagram How relays are shown on R & Mdiagram, all protection schemes, core of CT’s, tripping circuit, trip & lockout CT and its coresCTPolarity at primary and secondary sidesProtection and metering coresMetering core circuitProtection core circuitBackup over current protection connections at R & M SLDTransformer bay connection to Breaker failure and protection coresHV & LVvector group, NGR connection, NGR over current, neutral over current at R & MSLDDifference between neutral and NGRover currentRestricted earth fault protection CTconnection & its zone at R & MSLDMechanical Protection from transformer at R & MSLDBusbar & earth switch, Voltage transformer arrangement at R & M SLD. Lock Relay 86Tripping Relay 94When to use 86 and where to use 94 relay in scheme. List of ApparatusACSupply circuit, ACSocket, AClight, AC lighting and heating, annunciationExternal and internal panel drawings symbolsMCBconnections, where to connect ODD & EVENterminals What mean by arrow signs & square shows for MCBsymbolAC Loop failure indicationACannunciator circuitDCSupply CircuitDC supply change over circuitRedundancy of DCsupply explained & why it is providedWhat mean of dash dot lines in drawingsHow dc supply change over circuit works if one supply fail. What is loop in drawings and naming of loopUnderstand DCsupply supervision & loop supervision, what is difference between themTracking loop across drawings and check till endExplained Current Transformer circuit of Differential protection & over current protection Zone of differential protectionShorting facility of CT circuitWhy CTcircuit should be short circuited all the time & must never be open circuitedExplained Test Block, Use of test blockHow to inject current through testerCT connection of REFprotectionZone of REFProtectionWhy lockout contacts are used in parallel to high impedance lockout relayOver voltage protection in REF protectionRelay power supply connectionRelay watch dog contactTest block contact 13-14 for relay powering up. test plug cover when removed relay is powered off. Difference between tripping and lockout relaysHow to reset lockout relays, mechanical & electrical resetBinary input circuit of relaysOperation of lockout relaysCircuit of Tripping and lockout relaysComplete details of contacts of lockout relaysTrip Coil 1 & 2 circuit Breaker Failure initiation Trip circuit supervision relaySupervision relay working when circuit breaker is in open / close positionClose Block feature, why its is required, circuit of close block Alarm and SCADA circuitDevice detail & panel layout. Best Regards
