COURSE NAME:Low, Medium and High Voltage switchgear Fundamentals & Performance


This course can be scheduled at your convenience, to request this course please click here

Switchgear plays an important role in electricity distribution and its performance significantly affects the overall performance of the system. Failure to efficiently disconnect faults elsewhere in the network or failure in switchgear itself is costly, resulting in additional loss of supply, damage to equipment and possibly fatal injury to personnel.

It is therefore critically important that switchgear is operated and maintained correctly, within an overall asset management regime that is both economic and effective in securing a high level of system reliability.

This training course focuses on low, medium, and high voltage switchgear, which comprises by  far the bulk of switchgear on most electricity distribution systems. The emphasis is primarily on oil, air blast, SF6 and vacuum circuit breakers, but other forms of LV,MV & HV switchgear, for example ring main units and auto reclosers will also be described. Also, This training course will discuss the application, installation, maintenance and testing issues relating to low, medium, and high voltage switchgear and circuit breakers.



On successful completion of this course, delegates will understand how:

  • To develop fundamentals & performance of LV, MV and HV switchgear.
  • To provide methods and devise solutions for electrical problems encountered during connection and maintenance.
  • To maintain a continuing understanding of tests carried out on circuit  breakers ,and recording systems used in maintenance and troubleshooting of switchgear
  • The design, functionality and failure modes of switchgear systems.
  • To consolidate and update understanding of electrical safety during maintenance of switchgear systems.


Day 1: Introduction to Switchgear

  • · Single line diagrams – what is a power network? Why different voltage levels?
  • · Network components – active and passive  – typical examples
  • · Simple busbar and substation layouts – layouts – protection and control circuits
  • · Fault Levels & MVA rating of equipment
  • · Measuring transformers VT’s and CT’s
  • · Circuit breaker utilization, disconnector  operation and earthing switches
  • · Fuses - LV and HV fuses. Fuse gear
  • · Air break switches
  • · MCC’s for LV distribution boards
  • · Rating of switchgear - normal and fault duties
  • · Selection and checking for correct  switchgear ratings  - LV, MV, HV and EHV


Day 2:  Distribution Switchgear

  • · Primary substations – name plate data
  • · Device function numbers – suffix letters, main devices and auxiliary devices
  • · Vacuum Switchgear up to 36kV
  • · Description of equipment  – front, rear, cable entry and busbars
  • · Vacuum principles of interruption
  • · Air and SF6 external insulation of busbars and vacuum interrupters
  • · Oil breakers
  • · Maintenance requirements air, oil, vacuum and  SF6


Day 3: Switching, Safety and Earthing Requirements

  • · Busbar configurations – single, double, sectionalized and breaker and a half
  • · Main substation earthing and bonding
  • · Step and touch potentials – danger to personnel
  • · Routine testing and certification of substation earthing
  • · Interrupter classification - mechanisms, motor - spring, hydraulic and solenoid
  • ·Switching Requirements – interrupting time
  • · Auto - reclosing considerations – ring main and radial circuits


Day 4: HV Gas Insulated Switchgear and Auxiliary Plant Maintenance

  • · 145kV, 3 phase arrangement and single 275/400kV SF6 arrangements
  • · Arc characteristics  closing and opening – short circuit testing
  • · Switchgear ancillaries, measurement CTs, VTs, relays 
  • · Decomposition of arced SF6  Handling contaminated materials – disposal!
  • · Equipment required for maintenance – investigating leaks
  • · Mechanism testing and auxiliary relay contact circuits – trip coils open/close
  • · Contact trip timing tests and record interpretation – contact resistance tests
  • · Fault recording and reporting – national data base of faults
  • · Maintenance records



Day 5: Maintenance and Testing

  • · Health and Safety in Substations
  • · Mechanisms of deterioration of insulation
  • · MCC testing and refurbishment - contacts and arc chutes
  • · Trouble shooting  – use of diagrams and manufacturers manuals
  • · Block diagrams, line diagrams, wiring diagrams, interlock diagrams
  • · Required maintenance – condition, heaters, fuses, mechanism, overhaul
  • · Weekly, monthly, yearly program of maintenance – 5 years and more?
  • · Principles of circuit breaker maintenance – mechanisms and mechanical aspects


This course is directed at anyone who would like to expand their knowledge of preventive maintenance of switchgear and protection of electrical networks.

    • 5 Day(s)

    The presentation is generally appealing to me. The dedication & devotion of the instructor are both laudable & admirable.
    Mohammed F. Alotaibi

    Really this course is important for any inspector, so I will recommended it for our employees. And thanks a lot!
    Ahmed Al-Yami

    You are doing excellent bringing such very talented instructor. Please keep it up.
    Ahmed Afifi
    Al-Zamil CoolCare

    I would like to appreciate you as well as the instructor for a good training due to the fact that the helping to gain new information about the types of valve with advantages and disadvantage as well. Many thinking.
    Zaki Ali Aldawood

    This course was very beneficial and helpful to understand one of the Major NDT method. I encourage ITC to continue with this performance.
    Talal Saad AlHasawi

    ITC service was in overall excellent. Thanks.
    Wael M. Morsy

    This course was good and a nice guide to the PMP exam. Thanks.
    Yazeed Mohamed Mreki
    General Authority of Civil Aviation (GACA)

    It was good course & good preparation with excellent instructor. Thanks a lot.
    Faisal Mahdi Al-Qahtani

    It was a nice course to have. I suggest taking this course with the same instructor to other people. Thanks for the instructor for his kindness & helfull during the course.
    Abdul-Moniem Al-Humoud

    It is very important course, which enable us to improve our knowledge to work approaching our big account and can be recall us the key account. This is will support us to active result for the best of the Co.
    Mohammed Amjad
    Al-Suwadi Services

    The instructor is highly and technical knowledgeable in explaining all the subject in the course taken.
    Noel V. Garan
    Coldstorec Group Of Saudi Arabia

    Instructor was well prepared and knowledgeable I gain lot of useful information.
    Gulam Khan
    Saudi Aramco

    It was a good learning experience. Got to know the concept involved in key account.
    Muthuraman Nachiappan
    Al-Suwadi Services

    The instructor Mr. Ahmed Sabry has a very nice spirit.
    Salam Fakhoury
    Al Khodari Company

    It is very useful to us and increase our knowledge.
    Mohammed Rashed Afifi
    Al Khodari Company

    The course is excellent and helpful. It help me in organizing the work in more safe manner.
    Muzammil Hayat
    Al Khodari Company

    The instructor is very knowledge and hard working, his way of teaching is very good.
    Ibrahim Darwish
    Al Khodari Company