Transformer & Switchgear PD Monitoring

Minimize the Risk of In Service Failure
During the last few decades, maintenance professionals have grown to appreciate the importance of monitoring medium voltage (4 kV to 28 kV) metal enclosed bus. Despite best efforts by manufacturers in the design of bus for indoor and outdoor applications, switchgear is not immune to aging and degradation mechanisms, particularly in industrial environments. Failure investigations reveal the link to electrical tracking between phases or phase-to-ground, and across non-metallic insulating components that support the bus.

The failure process involves contaminants (pollution) and moisture condensation. Accumulation of partly conductive airborne particles on the insulation surface results in the flow of capacitive currents that lead to discharges, and subsequently to the carbonization of organic components of the contaminants. Furthermore, poorly cast current transformers (CTs) and potential transformers (PTs) may have internal insulation voids. These voids result in partial discharge (PD) activity that will eventually bore a hole through the insulation and result in a failure to ground.

Improve Predictive Maintenance Program for your Switchgear
Traditional off-line methods of monitoring switchgear for PD activity require considerable investment (e.g. an expert to perform the measurement during scheduled outages). The techniques developed by Iris Power for motor and generator PD monitoring have now been extended to provide cost effective and reliable monitoring systems for metal clad switchgear and bus. The advantages to a maintenance department seeking to enhance reliability are as follows:
Low testing costs.

Once the sensors are installed, maintenance personnel perform periodic measurements during normal operation. In the case of a continuous monitor, the alarm levels are set to provide a warning of increasing PD activity.

Iris Power can provide support to assist in the installation and calibration of systems (if requested), and to help plan your outage by identifying the section(s) of the switchgear or bus duct that are at risk and require corrective action(s).

Trending of data and support with interpretation from Iris.
The instrumentation and hardware required to perform on-line PD testing on large rotating machines (i.e. motors and generators) is compatible with that required for bus monitoring. Hence, if your plant already owns the Iris TGAB technology, you can use the same test equipment and procedures for bus monitoring, improving the return on your investment.

What needs to be done to start monitoring PD on switchgear?
To find out what needs to be done to start monitoring PD on switchgear contact IRIS Power.