Articles
HV Operation Responsibility Cost: Pricing Factors and the EMO Fee Tariff
2026-07-09T00:00:00+03:00
High voltage operation responsibility cost depends on transformer power, MV switchgear count, visit frequency and the EMO minimum fee tariff. Pricing factors.
YGTIS Certificate and Operation Manager Verification: Authority, Validity and Checks
2026-07-09T00:00:00+03:00
The YGTIS certificate is the high voltage facility operation responsibility authorisation, valid for five years. How to verify an engineer via EMO.
Duties of a Transformer Operation Manager: Inspection, Switching, Maintenance and Records
2026-07-09T00:00:00+03:00
A transformer operation manager inspects the substation periodically, directs switching, oversees maintenance and keeps records. Duties explained here.
Is HV Operation Responsibility Mandatory? Legal Basis, Scope and Exceptions
2026-07-09T00:00:00+03:00
For every facility with a 1 kV-and-above transformer, high voltage operation responsibility is legally mandatory. Legal basis, scope and exceptions.
What Is a DC Insulation (Megger) Test? What Does It Do, How Is It Performed and Why Is It Used?
2026-03-08T00:00:00+03:00
What is a DC insulation megger test, what does it do and how is it performed? The operating logic of this method that measures insulation resistance with DC test voltage, which equipment it is used on, what a megger device measures, its difference from a hipot test, evaluation approach and points requiring attention are explained in plain language.
What Is an AC Insulation Test Performed with Tan Delta and Capacitance Measurement? What Does It Do, How Is It Performed and Why Is It Used?
2026-03-08T00:00:00+03:00
How is an AC insulation test performed with tan delta and capacitance measurement and what does it do? The operating logic, difference from a conventional AC hipot test, application areas, advantages and points requiring attention of capacitance and tan delta measurements performed through an AC-based dielectric diagnostic approach are explained in plain language.
What Is a DC Hipot Test? What Does It Do, How Is It Performed and Why Is It Used?
2026-03-07T00:00:00+03:00
What is a DC hipot test, what does it do and how is it performed? The operating logic, application areas, effect on insulation withstand, difference from AC and VLF testing, advantages, limitations and points requiring attention of this method known as direct-current high-voltage testing are explained in plain language.
What Is a VLF Test? What Does It Do, How Is It Performed and Why Is It Used?
2026-03-06T00:00:00+03:00
What is a VLF test, what does it do and how is it performed? The operating logic of this high-voltage test method known as Very Low Frequency, why it is preferred for medium-voltage cables, its difference from AC and DC hipot tests, application areas, advantages and points requiring attention are explained in plain language.
What Is a Unit Protection Relay? How It Works
2026-03-05T00:00:00+03:00
What is a unit protection relay and how does it work? Differential protection of a generator-transformer unit within a single protection zone explained.
What Tests and Maintenance Are Required for Unit Protection Relays?
2026-03-05T00:00:00+03:00
What tests and maintenance are required for unit protection relays? Secondary injection, differential protection testing, auxiliary function verification, CT-VT chain check, trip circuit, binary inputs and outputs, event records and periodic maintenance steps are explained in plain language.
What Tests and Maintenance Are Required for Breaker Failure and Busbar Protection Relays?
2026-03-04T00:00:00+03:00
What tests and maintenance are required for breaker failure and busbar protection relays? Busbar differential characteristic verification, zone and check zone tests, breaker failure start logic, retrip and backup trip circuits, CT chain, disconnector status information, binary inputs and outputs, event records and periodic maintenance steps are explained in plain language.
What Are Breaker Failure Protection and Busbar Protection Relays? What Do They Do, How Do They Work and Why Are They Used?
2026-03-03T00:00:00+03:00
What are breaker failure protection and busbar protection relays, what do they do and how do they work? Breaker failure protection and busbar differential protection logic, internal and external fault distinction, zone selection, trip scenario, CT information and their effects on switchyard safety are explained in plain language.
What Tests and Maintenance Are Required for Overcurrent and Earth Fault Protection Relays?
2026-03-02T00:00:00+03:00
What tests and maintenance are required for overcurrent and earth fault protection relays? Secondary injection, pickup and time curve verification, I>, I>>, I0>, I0>> stages, CT and CBCT chain, directional earth fault protection test, trip circuit, binary inputs/outputs and periodic maintenance steps are explained in plain language.
What Is an Overcurrent and Earth Fault Protection Relay? What Does It Do, How Does It Work and For What Purpose Is It Used?
2026-03-01T00:00:00+03:00
What is an overcurrent and earth fault protection relay, what does it do and how does it work? Phase overcurrent and earth fault protection logic, I>, I>>, I0>, I0>> stages, IDMT and instantaneous trip structures, residual current measurement, application areas and protection coordination are explained in plain language.
What Is a Protection Relay? How It Works and Types
2026-02-21T00:00:00+03:00
What is a protection relay and how does it work? Fault detection, trip logic, overcurrent, earth fault, differential and distance relay types explained.
What Are Relay Setting Calculations? How Are They Performed?
2026-02-20T00:00:00+03:00
What are relay setting calculations and how are they performed? Pickup, time curve, TMS, instantaneous trip, earth fault settings and selectivity explained.
What Is Short-Circuit Analysis? What Does It Do, How Is It Performed and Why Is It Necessary?
2026-02-19T00:00:00+03:00
What is short-circuit analysis, what does it do and why is it performed? The purpose of short-circuit analysis performed to calculate possible fault currents in electrical installations, three-phase and earth faults, symmetrical and asymmetrical currents, equipment selection, protection coordination and safety effects are explained in plain language.
What Tests and Maintenance Are Required for Power Quality Analyzers?
2026-02-18T00:00:00+03:00
What tests and maintenance are required for power quality analyzers? Visual inspection, terminal and connection tightness, CT/VT circuits, communication infrastructure, display and event records, accuracy verification, thermal inspection and periodic check steps are explained in plain language.
What Is a Power Quality Analyzer? What Does It Do, How Does It Work and What Does It Measure?
2026-02-14T00:00:00+03:00
What is a power quality analyzer, what does it do and how does it work? The purpose, difference from an electricity meter, measured parameters and application areas of power quality analyzers that monitor voltage, current, power, energy, power factor, demand, harmonics and power quality data in electrical systems are explained in plain language.
What Tests and Maintenance Are Required for Electricity Meters?
2026-02-10T00:00:00+03:00
What tests and maintenance are required for electricity meters? Visual inspection, terminal and connection tightness, seal and cover checks, CT/VT circuits, accuracy verification, communication connections, thermal inspection and periodic metrological checks are explained in plain language.
What Is an Electricity Meter? Types and How It Works
2026-02-08T00:00:00+03:00
What is an electricity meter and how does it work? Energy measurement, active and reactive energy, mechanical, electronic and smart meter types explained.
What Tests and Maintenance Are Required for Power Factor Correction Systems?
2026-02-06T00:00:00+03:00
What tests and maintenance are required for power factor correction systems? Capacitor banks, contactors, fuses, reactors, power factor relay, current transformer connections, thermal inspection, harmonic effects and panel maintenance steps are explained in plain language.
What Is Power Factor Correction and Why Is It Needed?
2026-02-03T00:00:00+03:00
What is power factor correction and how does it work? Reactive power balance, capacitor banks, automatic correction panels and harmonic effects explained.
What Tests and Maintenance Are Required for OLTCs?
2026-02-02T00:00:00+03:00
What tests and maintenance are required for OLTCs? Motor-drive mechanism, tap-changing behavior, diverter and selector section, oil health, auxiliary contacts, protective relays, dynamic resistance measurement and condition-based diagnostic methods are explained in plain language.
What Is an OLTC? What Does It Do, How Does It Work and For What Purpose Is It Used?
2026-01-30T00:00:00+03:00
What is an OLTC, what does it do and how does it work? Voltage regulation, operating logic, main parts, difference from an off-circuit tap changer and application areas of this transformer tap-changing system known as an on-load tap changer are explained in plain language.
What Tests and Maintenance Are Required for Metal-Clad Switchgear?
2026-01-29T00:00:00+03:00
What tests and maintenance are required for metal-clad switchgear systems? Visual inspection, compartment cleaning, withdrawable circuit breaker and shutter mechanism, interlock tests, busbar and cable compartment checks, contact resistance, insulation, secondary circuits and thermal inspection are explained in plain language.
What Is Metal-Clad Switchgear? What Does It Do, How Does It Work and What Features Does It Have?
2026-01-27T00:00:00+03:00
What is metal-clad switchgear, what does it do and how does it work? The definition of medium-voltage metal-clad switchgear, separate metal compartment logic, withdrawable circuit breaker structure, difference from metal-enclosed systems, application areas and selection criteria are explained in plain language.
What Tests and Maintenance Are Required for RMUs?
2026-01-25T00:00:00+03:00
What tests and maintenance are required for RMUs? Visual inspection, mechanical operation and interlock verification, gas pressure indicator, cable compartment, grounding connections, contact resistance, secondary circuit checks and thermal inspection are explained in plain language.
What Is an RMU? What Does It Do, How Does It Work and What Parts Does It Include?
2026-01-23T00:00:00+03:00
What is an RMU, what does it do and how does it work? The structure, duties, ring supply logic, load-break switch and circuit-breaker types, application areas and selection criteria of this compact medium-voltage switching system known as Ring Main Unit are explained in plain language.
What Tests and Maintenance Are Required for MV Cable Terminations?
2026-01-19T00:00:00+03:00
What tests and maintenance are required for MV cable terminations? Visual inspection, surface cleaning, stress control area inspection, connection tightness, screen and grounding arrangement, thermal camera check, partial discharge, VLF and tan delta approach are explained in plain language.
What Is an MV Cable Termination? What Does It Do, How Does It Work and What Types Are There?
2026-01-18T00:00:00+03:00
What is an MV cable termination, what does it do and how does it work? The duties, stress control structure, indoor and outdoor types, plug-in solutions, difference from a cable joint and application areas of this medium-voltage cable accessory are explained in plain language.
What Tests and Maintenance Are Required for MV XLPE Cables?
2026-01-15T00:00:00+03:00
What tests and maintenance are required for MV XLPE cables? Visual inspection, route review, termination and cable joint inspection, screen-grounding continuity, sheath test, insulation assessment, VLF, tan delta, partial discharge and thermal inspection are explained in plain language.
What Tests and Maintenance Are Required for Transformer Differential Protection Relays?
2026-01-11T00:00:00+03:00
What tests and maintenance are required for transformer differential protection relays? Secondary injection, differential and restraint characteristic testing, inrush blocking verification, CT polarity and ratio checks, vector group compensation, trip circuit, binary inputs and outputs, and event records are explained in plain language.
What Is a Transformer Differential Protection Relay? How It Works
2026-01-09T00:00:00+03:00
What is a transformer differential protection relay and how does it work? 87T current comparison, percentage differential and inrush blocking explained.
What Is an MV XLPE Cable? What Does It Do, How Does It Work and What Structure Does It Have?
2026-01-06T00:00:00+03:00
What is an MV XLPE cable, what does it do and how does it work? The structure, XLPE insulation logic, screen layers, application areas, advantages and selection criteria of this cable used in medium-voltage power transmission are explained in plain language.
What Tests and Maintenance Are Required for Distance Protection Relays?
2026-01-06T00:00:00+03:00
What tests and maintenance are required for distance protection relays? Secondary injection, Zone 1 Zone 2 Zone 3 verification, direction determination, CT/VT circuits, trip circuit, teleprotection, event records and periodic maintenance steps are explained in plain language.
What Is a Distance Protection Relay? How It Works
2026-01-05T00:00:00+03:00
What is a distance protection relay and how does it work? Apparent impedance logic, Zone 1-2-3 structure and mho and quadrilateral characteristics explained.
What Is High Voltage Operation Responsibility? Why Is It Necessary and What Does It Cover?
2026-01-02T00:00:00+03:00
What is high voltage operation responsibility, why is it necessary and which works does it cover? Operational safety, switching order, maintenance coordination, single-line diagram, grounding tests, periodic reporting and authorized engineer responsibility in HV installations are explained in plain language.
What Tests and Maintenance Are Required for Transformers?
2025-12-30T00:00:00+03:00
What tests and maintenance are required for transformers? Visual inspection, oil and insulation health, DGA, ratio test, winding resistance measurement, bushing checks, thermal inspection, OLTC, cooling equipment and dry-type transformer cleaning and maintenance steps are explained in plain language.
What Tests and Maintenance Are Required for Line Traps?
2025-12-22T00:00:00+03:00
What tests and maintenance are required for line traps? Visual inspection, main coil and tuning unit inspection, connection tightness, mounting structure, jumper checks, insulators and support elements, thermal inspection and PLCC performance verification are explained in plain language.
What Tests and Maintenance Are Required for High-Voltage Lines?
2025-12-21T00:00:00+03:00
What tests and maintenance are required for high-voltage lines? Line patrols, pole and tower checks, conductor and accessory inspections, insulator checks, shield wire and grounding verifications, thermal inspection, corridor maintenance and record management are explained in plain language.
What Is a Line Trap? What Does It Do, How Does It Work and Where Is It Used?
2025-12-20T00:00:00+03:00
What is a line trap, what does it do and how does it work? The duty of this equipment, also known as a wave trap, in PLC/PLCC communication, its carrier frequency behavior, effect on power frequency, relationship with coupling capacitors and application areas are explained in plain language.
What Is a High-Voltage Line? Components and How It Works
2025-12-15T00:00:00+03:00
A high-voltage line carries electrical power over long distances with low losses. Learn its conductors, towers, insulators, shield wire and safety clearances.
What Tests and Maintenance Are Required for Insulators?
2025-12-03T00:00:00+03:00
What tests and maintenance are required for insulators? Visual inspection, surface contamination and crack inspection, mechanical connections, cleaning, UV/IR inspection, leakage current approach and detailed diagnostic steps when required are explained in plain language.
What Is an Insulator? Function, Types and Selection
2025-11-16T00:00:00+03:00
What is an insulator and what does it do? Electrical insulation and mechanical support, porcelain, glass and composite insulator types and selection.
What Tests and Maintenance Are Required in Transformer Substations?
2025-11-15T00:00:00+03:00
What tests and maintenance are required in transformer substations? The main maintenance and test steps in a transformer substation are explained in plain language, including power transformers, circuit breakers, disconnectors, earthing switches, instrument transformers, surge arresters, protection relays, grounding system, auxiliary DC supplies and thermal checks.
What Tests and Maintenance Are Required for Earthing Switches?
2025-11-14T00:00:00+03:00
What tests and maintenance are required for earthing switches? Visual inspection, cleaning, contact surfaces, mechanical movement, interlock and position verification, grounding continuity, auxiliary contacts, connection tightness and required electrical checks are explained in plain language.
What Is an Earthing Switch? What Does It Do, How Does It Work and Where Is It Used?
2025-11-13T00:00:00+03:00
What is an earthing switch, what does it do and how does it work? The duty of this equipment, also known as an earthing blade, its difference from a disconnector and a circuit breaker, its use in MV switchgear, interlock structure and making capacity onto short circuit are explained in plain language.
What Is a Transformer Substation? What Does It Do, How Does It Work and Which Sections Does It Consist Of?
2025-11-13T00:00:00+03:00
A transformer substation converts the voltage of electrical energy and handles switching, protection, metering and distribution. Sections and types explained.
What Is a Transformer? Operating Principle, Types and Applications
2025-11-10T00:00:00+03:00
A transformer converts the voltage level of AC power by electromagnetic induction. Working principle plus power, distribution, dry-type and oil types explained.
What Is High Voltage? Limit Values, Applications and Safety
2025-11-10T00:00:00+03:00
What is high voltage, which voltage levels are considered HV and where is it used? LV-MV-HV limit values, high-voltage lines and transformer substation examples, high-voltage applications in transmission and distribution lines and basic safety rules are explained in plain language.
What Tests and Maintenance Are Required for Surge Arresters?
2025-11-09T00:00:00+03:00
What tests and maintenance are required for surge arresters? Visual inspection, surface contamination and crack inspection, connection and grounding checks, surge counter and disconnector verification, thermal inspection, leakage current evaluation, watts-loss and insulation tests are explained in plain language.
What Is a Surge Arrester? How It Works and Its Types
2025-11-06T00:00:00+03:00
What is a surge arrester and how does it work? MOV-based overvoltage protection against lightning and switching surges, arrester types and selection.
What Tests and Maintenance Are Required for Disconnectors?
2025-11-05T00:00:00+03:00
What tests and maintenance are required for disconnectors? Visual inspection, cleaning, mechanical movement check, contact surfaces, interlock structures, position indicators, connection tightness, contact resistance measurement, insulation checks and operating verification together with the earthing switch are explained in plain language.
What Is a Disconnector? Function, Operation and Types
2025-11-03T00:00:00+03:00
What is a disconnector and what does it do? Visible isolation, no-load operation, difference from a circuit breaker and MV disconnector types explained.
What Tests and Maintenance Are Required for Circuit Breakers?
2025-11-02T00:00:00+03:00
What tests and maintenance are required for circuit breakers? Visual inspection, mechanical maintenance, opening-closing coils, auxiliary contacts, timing test, contact resistance measurement, insulation checks, minimum operating voltage, lubrication and maintenance steps specific to vacuum or SF6 circuit breakers are explained in plain language.
What Is a Circuit Breaker? What Does It Do, How Does It Work and What Types Are There?
2025-11-01T00:00:00+03:00
A circuit breaker safely makes and breaks normal and fault currents. Its duties, vacuum and SF6 types, difference from a disconnector and selection explained.
What Tests and Maintenance Are Required for Voltage Transformers?
2025-10-28T00:00:00+03:00
What tests and maintenance are required for voltage transformers? Visual inspection, cleaning, primary fuse and connection checks, secondary circuit verification, ratio and polarity tests, burden assessment, insulation tests and capacitance and dissipation factor checks for CVTs are explained in plain language.
What Is a Voltage Transformer? What Does It Do, How Does It Work and Where Is It Used?
2025-10-27T00:00:00+03:00
What is a voltage transformer and what does it do? Operating principle, parallel connection, secondary voltages, inductive and capacitive VT types explained.
What Tests and Maintenance Are Required for Current Transformers?
2025-10-26T00:00:00+03:00
What tests and maintenance are required for current transformers? Visual inspection, cleaning, connection checks, ratio test, polarity test, accuracy check, burden assessment, insulation, excitation and primary injection verification are explained in plain language.
What Is a Current Transformer? What Does It Do, How Does It Work and How Is It Selected?
2025-10-25T00:00:00+03:00
What is a current transformer, what does it do and how does it work? The operating principle of current transformers used for measurement and protection, 1 A and 5 A secondary structures, current transformer ratio, accuracy class, burden value, connection rules and selection criteria are explained in plain language.