• Post category:StudyBullet-11
  • Reading time:16 mins read


Electrical Power System Protection, Wiring Diagram, Drawing

What you will learn

Transformer protection panel schematics

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.

Description

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.


Get Instant Notification of New Courses on our Telegram channel.


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

English
language

Content

Introduction

Introduction

List of contents

List of contents

General Arrangement Drawing

General Arrangement Drawing

Symbols and Legends

Symbols and Legends

Protection and Relay Metering Diagram

Protection and Relay Metering Diagram

List of Apparatus

List of Apparatus

AC Supply Indication

AC Supply Indication

DC Supply Circuit

DC Supply Circuit

Understand Loop and Loop supervision

Understand Loop and Loop supervision

CT Circuit of Differential, OC, REF Protection

CT Circuit of Differential, OC, REF Protection

Relays Power Supply Connection

Relays Power Supply Connection

Difference between tripping and lockout relays

Difference between tripping and lockout relays

Electrical Reset of Lockout relays

Electrical Reset of Lockout relays

Binary Input of relays

Binary Input of relays

Operation of Lockout relays

Operation of Lockout relays

Complete details of contacts used in lockout relays

Complete details of contacts used in lockout relays

Tripping Circuit

Tripping Circuit

Understand Trip Circuit Supervision Circuit

Understand Trip Circuit Supervision Circuit

Close Block Circuit of Lockout Relay

Close Block Circuit of Lockout Relay

Alarm and SCADA Signals

Alarm and SCADA Signals