Case Study: TOTUS Online monitoring prevents in-service failure of 345kV bushing in North America

Evidence: An arcing event was recorded in conjunction with a capacitance increase in the same bushing

Action: DGA test of bushing oil confirmed the arcing activity, leading to immediate bushing replacement

Background

TOTUS Bushing and PD monitoring was installed in 2018 on a 504 MVA three-phase transformer in North America.

The TOTUS bushing monitoring system continuously monitors bushing leakage current and partial discharges, summarizes the data hourly, stores this digitally and makes it accessible remotely.

Unique features of TOTUS include the ability to automatically reject noise, separate PD in bushings from those in the main tank and detect intermittent Arcing activities that can be correlated with other parameters such as bushing capacitance, load and temperature.