Radiated Energy; Full Illustration - Baur PD-SGS User Manual

P roduc t information
3.2.1

Radiated energy

A PD event will radiate energy in different forms and this energy can be picked up by the
PD-SGS in order to detect the source and locate it.
Electromagnetic radiation
PD creates electromagnetic (EM) radiation that dissipates in all directions away from the
source. Metal components, for instance the panels around switchgear, will pick up this
radiation and small voltages called Transient Earth Voltages (TEVs) are induced on the
surface. These very high frequency signals will be picked up by the PD-SGS and indicate
that there is a PD source nearby.
Acoustic radiation
Partial discharge also generates acoustic energy across a wide band of frequencies. This
acoustic energy can be detected in the ultrasonic range when there is a 'line of sight'
between the PD source and the detecting sensor. Sharp points, for instance on air insulated
cable terminations, are typical sources of corona that will produce acoustic emission. Cast
insulators are prone to surface tracking where electrical stress across the insulator's surface
causes discharge, and deteriorates the insulator surface and creates carbon tracks. This can
lead to flashover and failure of the equipment.
3.3

Full illustration

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1 Transport case
2 Handheld online PD detector PD-SGS
3 PD-SGS power supply / charger
4 Function tester PD-FT
5 Stereo headphones
P D-S G S
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