POWER & DISSIPATION FACTOR

TAN DELTA TESTING

At Power Products and Solutions, we offer Tan Delta testing to help monitor and assess the condition of aging infrastructure and cables used in medium to high-voltage systems.

What is Tan Delta Cable Testing?

Tan Delta cable testing detects issues in cable insulation like water trees, a form of insulation degradation that may not be apparent in VLF testing. Tan Delta testing is particularly effective for monitoring the aging of insulation and assessing the impact of moisture.



“Tan Delta” measures energy loss in insulation material. It measures the ratio of (lossy) current to the capacitive (useful) current in the insulation. A gradual increase in the Tan Delta value signals that the insulation is deteriorating and needs maintenance.

Power Factor vs Dissipation Factor

Tan Delta testing is often referred to as 'Power Factor and Dissipation Factor testing' because it evaluates closely related aspects of insulation performance: power factor and dissipation factor.

Power Factor

Measures the overall efficiency with which insulation handles electrical power, and how much energy is being stored and used.

Dissipation Factor

The extent to which the cable insulation loses energy 'dissipates' as heat.

Reasons to Have Tan Delta Testing Performed

Since Tan Delta testing helps assess the condition of aging cables, this test is ideal for determining deterioration caused by normal aging or moisture or contamination.

If your facility has experienced any moisture-related insulation cable degradation, Tan Delta testing will be able to detect this moisture, including tree-shaped channels.

By performing Tan Delta testing as part of predictive maintenance, you can assess patterns of insulation degradation. Increases in the Tan Delta value will indicate that insulation is deteriorating and help your facility prioritize and schedule electrical maintenance work before a failure occurs.