Izolatory

Izolatory, in electrical engineering often referred to simply as insulators, are devices that provide electrical isolation and mechanical support for conductors in power systems. They are designed to carry no current in normal operation between energized parts and grounded or other non-energized components, and to withstand the electrical and mechanical stresses present in the system. Their main role is to prevent unwanted current flow while keeping conductors securely in place.

Most isolators are made from insulating materials such as porcelain (ceramic), glass, or polymer composites. They come in different configurations, including pin-type, suspension, strain (or post) isolators, and cap-and-pin variants. The form and material are chosen based on voltage level, environmental conditions, and required mechanical strength. Key design considerations include creepage distance, able to shed water and pollution, ultraviolet resistance, and resistance to mechanical impact and wind.

Performance and reliability depend on weather and contamination conditions. Pollutants, moisture, and salt can reduce dielectric strength and lead to flashover if a circuit is opened under load. Polymer insulators often use hydrophobic surfaces to improve rain shedding, while ceramic insulators are valued for long-term aging stability. Regular maintenance may involve cleaning, inspection for cracks or glaze wear, and replacement of damaged units. Insulators are subjected to routine electrical and mechanical tests and adhere to standards issued by bodies such as IEC and ANSI to ensure safe operation in substations, transmission lines, and other high-voltage installations.

Typical applications include overhead transmission and distribution lines, substation equipment, and specialized electrical installations where reliable electrical isolation and robust mechanical support are required.