Protection Signaling Equipment (PSE) forms the critical communication backbone for transmission line protection schemes in modern power systems. This technical guide explores the migration from legacy Digital (E1/G.703) interfaces to Optical Ethernet interfaces over MPLS networks, explaining the technical rationale, implementation challenges, and practical considerations for utilities and EPC contractors. This guide provides comprehensive technical…
Category: Extra High Voltage EHV Substation Design
Autotransformers in EHV Power Systems: Theory, Maths & Practice
Autotransformers are among the most misunderstood yet critically important assets in modern power systems. While they appear deceptively simple at low voltages, at EHV levels (380–500 kV) they become system-defining components that directly influence fault levels, insulation coordination, grounding, and grid stability. This article provides a complete, utility-grade explanation of autotransformers, covering theory, mathematics, IEC…
Auxiliary Transformer Sizing (Substation Primary Design Course)
In this post, we wil explain auxiliary transformer sizing, as per SEC/National Grid standards. Auxiliary transformers play a critical but often underestimated role in substation design. While power transformers transmit energy to the grid, auxiliary transformers ensure the substation itself stays alive—supplying power to protection, control, HVAC, lighting, motors, communication systems, and essential services.This is…
The Rise of SF6-Free Switchgear: Alternatives, Advantages, and the Road Ahead
SF₆-free switchgear is no longer a future concept. Manufacturers have already begun mass-producing equipment without SF₆, and many installations worldwide are operating successfully today. In this post, we will discuss the following: The End of SF6? Why the Electrical Industry is Going SF6-Free For over 50 years, Sulfur Hexafluoride (SF6) has been the backbone of the electrical…
Classification of Lightning Protection Systems
In this post we are providing you an overview of Classification of Lightning Protection Systems (LPS). Lightning Protection Systems (LPS) are categorized into four classes (I, II, III, and IV). This classification is based on the level of lightning protection required. These classes are defined in IEC 62305 (Protection Against Lightning). The higher the class…
Synchronous Condenser, STATCOM, STATCOM with BESS, and SVC
In modern power systems, maintaining voltage stability and reactive power balance is becoming more challenging — especially with the increasing share of renewable energy.Several technologies are used to provide reactive power support and grid stability. The most common ones are: Each of these solutions has its own advantages, depending on the type of system and…
How do you select cable size for a motor or load
Selecting the right cable size is important for both safety and efficiency. An undersized cable may overheat, cause voltage drops, or even lead to fire hazards. An oversized cable increases cost unnecessarily. Cable size is selected based on the following key factors: Current Carrying Capacity (Ampacity): The cable must handle the full-load current of the…
Difference between MCB, MCCB, ACB, and VCB
MCB, MCCB, ACB, and VCB are most common types of Circuit breakers. Circuit breakers are essential devices that we use to protect electrical systems from faults and overloads. They come in different types depending on the application, voltage level, and breaking capacity. MCB (Miniature Circuit Breaker) MCCB (Moulded Case Circuit Breaker): ACB (Air Circuit Breaker):…
Feeder Protection Signaling
High-voltage power systems like 380kV transmission lines are the backbone of modern grids. They carry electricity over long distances, and any fault (like a short circuit or flashover) the system must detect it instantly and isolate it to protect equipment and keep the grid stable. That’s where feeder protection signaling comes in. In this post,…
SEC Standards Update: New vs Old
Saudi Electricity Company (SEC) has issued new standards that mayl soon replace the old ones. These updated codes are essential for engineers, consultants, and contractors working on substations, OHTL (Overhead Transmission Lines), and power system projects in Saudi Arabia. Key Points to Remember: Our Most Read Posts In the old SEC standards, the first letter…