Learn Transformer Protection Panel Schematics

Learn Transformer Protection Panel Schematics, Electrical Power System Protection, Wiring Diagram, Drawing.

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 11/132/220/500kV Substation, 1263MW power plant, 660kV HVDC system.  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 page
• How page is divided in rows and columns
• How to track inter panel loops
• Drawing Revision No, Philosophy
• Drawing approval stages
• Why two ratings of transformer are mentioned on drawings
• Understanding Drawing number
• How Bay numbers are assigned
• How to define address of object at the page
• How to read list of content
• Ordering code , Origin, Make of items
• Details provided in GA drawings
• Color coding, wire size, relay types, alarm, annunciation details, why GA drawing are important during design and commissioning stage / Maintenace stage
• Generally, control wiring is grey, CT VT wiring RYB, trip ferrule in red color etc.
• Understand symbols & legends
• Symbol of CT, VT, Relays, Aux, push button, Load break switch, power contact of CB, limit switch etc
• Relay and metering diagram
• How relays are shown on R&M diagram, all protection schemes, core of CT’s, tripping circuit, trip & lockout
• CT and its cores
• CT Polarity at primary and secondary sides
• Protection and metering cores
• Metering core circuit
• Protection core circuit
• Backup over current protection connections at R&M SLD
• Transformer bay connection to Breaker failure and protection cores
• HV & LV vector group, NGR connection, NGR over current, neutral over current at R&M SLD
• Difference between neutral and NGR over current
• Restricted earth fault protection CT connection & its zone at R&M SLD
• Mechanical Protection from transformer at R&M SLD
• Busbar & earth switch, Voltage transformer arrangement at R&M SLD.
• Lock Relay 86
• Tripping Relay 94
• When to use 86 and where to use 94 relay in scheme.
• List of Apparatus
• AC Supply circuit, AC Socket, AC light, AC lighting and heating, annunciation
• External and internal panel drawings symbols
• MCB connections, where to connect ODD & EVEN terminals
• What mean by arrow signs  & square shows for MCB symbol
• AC Loop failure indication
• AC annunciator circuit
• DC Supply Circuit
• DC supply change over circuit
• Redundancy of DC supply explained & why it is provided
• What mean of dash dot lines in drawings
• How dc supply change over circuit works if one supply fail.
• What is loop in drawings and naming of loop
• Understand DC supply supervision & loop supervision, what is difference between them
• Tracking loop across drawings and check till end
• Explained Current Transformer circuit of Differential protection & over current protection
• Zone of differential protection
• Shorting facility of CT circuit
• Why CT circuit should be short circuited all the time & must never be open circuited
• Explained Test Block, Use of test block
• How to inject current through tester
• CT connection of REF protection
• Zone of REF Protection
• Why lockout contacts are used in parallel to high impedance lockout relay
• Over voltage protection in REF protection
• Relay power supply connection
• Relay watch dog contact
• Test block contact 13-14 for relay powering up.
• test plug cover when removed relay is powered off.
• Difference between tripping and lockout relays
• How to reset lockout relays, mechanical & electrical reset
• Binary input circuit of relays
• Operation of lockout relays
• Circuit of Tripping and lockout relays
• Complete details of contacts of lockout relays
• Trip Coil 1 & 2 circuit
• Breaker Failure initiation
• Trip circuit supervision relay
• Supervision relay working when circuit breaker is in open / close position
• Close Block feature, why its is required, circuit of close block
• Alarm and SCADA circuit
• Device detail & panel layout.

Best Regards