SF6 Leak Detection Solution
SF6 Leak Detection Solution
See the problem before it’s a problem!
SF6 breakers are critical to reliable operation of utility grids and, with increasing fleet age, are a target for continuous improvement of maintenance practices. The breakers’ importance, coupled with a growing focus on environmental stewardship, has led many utilities to investigate better ways to monitor SF6 breakers and minimize maintenance costs associated with SF6 leaks.
MISTRAS has developed a wireless SF6 Monitoring System to address the need for accurate low cost predictive monitoring and not traditional standalone alarm monitoring. The system combines the latest advances in sensor, processor, wireless mesh networking & energy harvesting technology and packaging with patented algorithms that accurately track gas loss that facilitates proactive rather than costly reactive maintenance.
The system was specifically designed in combination with a leading electric utility for easy installation and operation in rugged, high voltage environments. Installation does not require an outage or special training. The system is scalable where new sensor nodes can be added and configured in minutes. Once operationalthe system compensates for ambient temperature effects, removing the diurnal swings that make current density monitors problematic.
Information from the system is made available to users via a secured intranet web browser or can be interfaced to the utilities SCADA system. The system also interfaces to the OSIsoft PI System for custom visualization and data transfer to the utilities maintenance management system.
System Economics
Reactive maintenance can greatly exacerbate the impact to maintenance budgets. This is due to leaking breakers typically alarming on low levels of gas during non-working hours because low ambient night-time temperatures correlate with low uncompensated pressure readings and increased leakage. This causesthe unscheduleddispatch of personnel to “roll the truck” or dispatch a crew in an afterhours overtime call to remote substations.
Addressing both reduced overtime expenditures and greater environmental sustainability can be aided by a solid predictive SF6 maintenance program. Such a program must appropriately monitor SF6 pressures, accurately compensate for temperature, and highlight leak trends to provide the predictive scheduling of maintenance activities. These advanced features are what the MISTRAS SF6 monitoring system incorporates and provides.