Understanding Partial Discharge

Partial discharge occurs in and around the insulation material on HV equipment such as cables and switchgear. It is caused by gaps, voids, contamination and defects in the insulation and this is where small 'arcs' take place. Once this process starts, it only increases and can lead to failures, so being able to detect partial discharge as early as possible has major safety, financial and security of supply benefits.

Unlike measuring Volts and Amps, PD measurements can be difficult due to the sensitivity of the measurement and environmental conditions out in the field. EA Technology's UltraTEV Plus² has been designed based on feedback from electrical engineers around the world and the result is a major break-through for the use of hand-held PD instruments: 

The UltraTEV Plus² tells the operator if the measurements are real PD or if it’s noise or interference. It can capture measurements and transfer them via Wi-Fi, so inspection staff can record data and move on to the next job. All information is then available for PD and asset management experts to analyse, make comparisons, look for trends and integrate information into corporate asset management systems.

PD measurement on cables is possible with the UltraTEV Plus²; and new analytical tools are available to interpret more complex results. 

Brian Matthews, senior asset engineer and member of the Partial Discharge User Group, said: “After assessing the new instrument we have found the new analytical tools such as the phase resolved plots very helpful in identifying genuine Partial Discharge”. 

Anne McIntosh, director HV 5-9s, EA Technology, says: “EA Technology has listened to our customers around the world; they asked for better understanding of the results, better ways to record and manage the information and for increased functionality. The UltraTEV Plus² meets these challenges; accurate condition information can be easily measured and better decisions made to improve the reliability and safety of electrical networks”.