Dielectric loss testing is crucial to ensuring the safety and efficiency of electrical equipment by examining how insulating materials dissipate energy under voltage. The HVEX Tangent Delta automates this test, offering precision and safety in high-voltage applications. This technology not only ensures compliance with standards but also monitors device integrity over time, preventing failures and optimizing electrical performance.

Electrical equipment tests are procedures conducted to evaluate and ensure the performance, safety, and compliance of electrical devices according to standards and specifications. These tests are essential at various stages, from development and manufacturing, before delivering a product to the end consumer, to installation and equipment maintenance.

The primary objective is to ensure that electrical equipment complies with applicable standards and regulations and operates safely and efficiently.

These tests can include a variety of assessments such as electrical resistance tests, insulation tests, operational load tests, short-circuit protection tests, among others. In this blog, we will discuss measurement tests for dielectric loss factors, also known as insulation capacitance, and the Tangent Delta.

Dielectric materials are substances capable of resisting the flow of electrical current. They are characterized by their low electrical conductivity, meaning they do not allow electrical current to flow easily through them. Instead, when exposed to an electric field, dielectric materials polarize, creating an opposing electric field that counters the applied electric field.

These materials are used in a wide range of applications in electrical and electronic engineering, including:

 Dielectric materials are frequently used to insulate wires, cables, and electrical components, preventing short circuits and ensuring the safety of electrical circuits.

 In capacitors, dielectric materials separate conducting plates, allowing the capacitor to store electrical charges.

In electrical transformers, dielectric materials isolate the conducting coils, preventing electrical current from passing between them.

They are used in various electronic components such as transistors, integrated circuits, resistors, and inductors to provide electrical insulation and other specific electrical properties.

Some common examples of dielectric materials include glass, plastics, ceramics, and paper. Each dielectric material possesses unique electrical properties that make it suitable for different applications.

Dielectric losses refer to the energy dissipated as heat when a dielectric material is subjected to an alternating electric field. Dielectric materials are insulating materials that do not conduct electrical current significantly. When an alternating electric field is applied to these materials, elementary dipoles attempt to follow changes in the electric field, resulting in internal friction and, consequently, energy dissipation as heat.

This energy dissipation is called dielectric loss and is a critical characteristic to consider in applications where energy efficiency is crucial, such as in capacitors, transformers, electrical cables, and other electrical devices.

The Tangent Delta is a fully automatic equipment developed to perform measurement tests of dielectric loss factor (tan δ) and capacitance in various electrical equipment, such as transformers, bushings, capacitors, current transformers, and potential transformers.

Dielectric losses can have adverse effects on electrical materials, depending on the context and application. Some reasons why dielectric losses may be undesirable include:

When dielectric materials dissipate energy as heat due to dielectric losses, it can reduce the energy efficiency of the device. In devices like transformers or capacitors, where energy is stored and transferred, significant losses can result in lower efficiency and higher energy consumption.

 Dielectric losses can cause overheating of electrical components, which can lead to damage to dielectric materials, reduced device lifespan, and even premature failure.

 In high-frequency systems such as radio circuits or wireless communications, dielectric losses can attenuate signals and reduce data transmission quality.

 In some cases, dielectric losses can affect the stability and overall performance of the electrical system, especially in sensitive applications that require signal precision and stability.

To mitigate the negative impacts of dielectric losses, it is essential to anticipate this phenomenon through measurement tests of dielectric loss factors and insulation capacitances.

Measurement Tests of Dielectric Loss Factors

Measurement tests of dielectric loss factors are procedures performed to determine the magnitude of dielectric losses in a dielectric material or electrical system. The dielectric loss factor, also known as dissipation factor or tangent delta (tan δ), measures how efficiently a dielectric material can store and release energy when subjected to an alternating electric field.

One method to conduct these tests is by using the HVEX Tangent Delta.

During tests with the Tangent Delta, the dielectric material is exposed to an alternating electric field, measuring the relationship between lost power (dielectric losses) and total applied power. This is typically achieved by measuring current and voltage in the dielectric material, enabling automatic calculation of capacitance and tangent delta. This evaluation assesses the insulation capacity of the equipment and prevents undue energization.

Dielectric loss factor measurement tests are crucial for device quality control, ensuring dielectric materials meet desired performance specifications and have dielectric losses within acceptable limits. They also enable proactive maintenance and diagnosis, facilitating long-term material monitoring and identification of potential issues like insulation deterioration.

With an internal source of up to 12 kV, or the option of using an external source and capacitor, this device offers versatile applications, adapting to various testing needs, including high-voltage applications.

Renowned for its accuracy, the Tangent Delta employs digital waveform analysis and bridge autocalibration technology. Its multilevel protection ensures operational safety, with swift action in cases of short-circuit or dielectric breakdown at AT terminals.

Dielectric loss testing is crucial to ensuring the safety and efficiency of electrical equipment by examining how insulating materials dissipate energy under voltage.


Tangent Delta (Loss Factor) and Capacitance Tester

HVEX Tangent Delta Tester is a fully automatic device designed to perform tests measuring the Dielectric Loss Factor (tan δ) and capacitance in various electrical equipment, such as transformers, bushings, capacitors, current transformers, and potential transformers.

Dielectric Loss Tests and the Tangent Delta Equipment

Quote

Tangent Delta and Capacitance Tester

‌