👉 Qué son los SECCIONADORES ELECTRICOS en SUBESTACIONES ELECTRICAS de BAJA, MEDIA Y ALTA TENSION ⚡

What are Sectionalizers?

Introduction to Sectionalizers

• The video introduces the concept of sectionalizers, focusing on their definitions and real-life applications in electrical circuits.

• Sectionalizers serve four main functions: they must withstand nominal overload and short-circuit currents, provide visible or safe disconnection, maintain a grounded state when open, and operate without load.

Functions of Sectionalizers

• The first function is to handle nominal current levels during overload and short-circuit conditions; overload refers to currents above nominal levels while short-circuits can involve multiple times the nominal current.

• A visible cut-off is essential for safety; this ensures that operators can see when the circuit is open.

• Maintaining a grounded state when open prevents accidental reconnection under load conditions.

Types of Sectionalizers

• Different types exist based on operational power requirements (low, medium, high voltage), with specific designs like knife switches for low voltage applications.

• The construction includes two main parts: a base and movable blades that connect or disconnect the circuit.

Safety Features

• Some sectionalizers are designed to be operated remotely using poles to ensure safety from electric shock during maintenance.

• They must ensure that there’s no load present before opening; otherwise, damage may occur.

Additional Insights on Fuses

• Fuses integrated into sectionalizer systems act as protective devices against overcurrent by melting under excessive heat caused by high currents.

• Once a fuse operates due to an overload or short circuit, it cannot be reset until replaced; this ensures ongoing protection against faults.

Maintenance Procedures

• Proper procedures dictate that maintenance should only commence after ensuring all loads are disconnected from the transformer or equipment being serviced.

• Operators must verify that no voltage remains in the lines before proceeding with any work on electrical systems.

Understanding Unipolar and Bipolar Switches

Overview of Switching Mechanisms

• The discussion begins with the concept of unipolar switches, which allow current and voltage to flow through specific contacts when rotated.

• Bipolar switches are introduced, highlighting that they consist of two poles. Each pole is referred to as a "senador," with images showing both open and closed configurations.

Insulator Distances and Voltage Ratings

• The distance between insulators is crucial for voltage ratings; for example, at 145 kV, the distance is approximately 2.17 meters, while at 245 kV it increases to about 3.20 meters.

Operation of Sectionalizers

• Sectionalizers operate by contracting parts that elevate to make contact directly with the line. This mechanism ensures safe operation during maintenance or fault conditions.

Types of Switches and Their Functions

• Various types of switches are discussed, including rotary sectionalizers that function similarly but have different designs for operational efficiency.

• Tripolar sectionalizers are highlighted for their ability to connect multiple contacts simultaneously, allowing current passage effectively.

Remote Operation Capabilities

• Some switches can be operated remotely or manually from a control box located at the bottom, enhancing flexibility in managing electrical systems.

Symbols Used in Electrical Diagrams

• The presentation covers symbols used in electrical schematics for various devices like selectors and circuit interrupters, emphasizing their roles in circuit management.