Tangent Delta and Power Factor

Non-destructive analysis of HV asset insulation

TD/PF is a form of offline testing that comprises a non-destructive diagnostic technique that evaluates the condition of the insulation in assets such as motors, generators, and cables.

Measurements quantify the dielectric losses in the asset insulation, and can indicate potential issues such as moisture ingress, degradation or aging of the insulation.

A benefit of TD/PF testing is its ability to monitor changes in insulation over time, so by periodically measuring and recording these values within Atlas by Monitra™, analysis of condition trending helps to identify progressive degradation or anomalies in the insulation. As a result, TD/PF testing can serve as a vital tool in predictive maintenance programs.

Test Standards.

Power Cables

IEEE 400.2-2013

IEEE Guide for field testing of shielded power cable systems using very low frequency (VLF) (less than 1 Hz)

IEC 63206:2019

Submarine power cables with extruded insulation and their accessories for rated voltages from 6 kV (Um = 7.2 kV) up to 60 kV (Um = 72.5 kV)

Rotating Machines

IEC 60034-27-1:2017

Rotating electrical machines - Part 27-1: Off-line partial discharge measurements on the winding insulation

IEC 60034-27-3:2015

Rotating electrical machines - Part 27-3: Dielectric dissipation factor measurement on stator winding insulation of rotating electrical machines

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