On-Line Circuit Breaker Predictive Maintenance

From a number of perspectives the active devices in an electric power delivery system, the circuit breakers, can be characterized as the weakest links in the network, as opposed to the passive components such as lines and transformers. That said, the unerring action of switching devices is critical to power delivery quality and reliability.

INCON-optimizer2

Addressing this priority in an appropriate manner and timeliness, on-line power circuit breaker monitors are widely used today by maintenance groups for real-time reporting of breaker operating conditions. These monitors provide an effective means to predict and prevent breaker mis-operations and failures. With the availability of real-time data, scheduled maintenance procedures are giving way to cost-effective reactive maintenance plans to reduce maintenance costs and out-of-service time.

Digital electronic technology exists today that can monitor conditions such as arc extinguishment time, mechanism transit time, accumulated contact wear, the presence of restrikes, number of operations, and control circuit failure. Any of these can be used as a decision set point to implement incipient breaker failure remedial techniques which, given the extremely rapid on-set of breaker problems in the switching sequence itself, can even include real-time tripping integration into protection schemes.

Responding to the demand for such a device as an all-important retrofit option for existing or even new breakers, INCON USA have developed and released their “OPTImizer” product for this application. The OPTImizer offers reliable and cost-effective circuit breaker wear and condition monitoring in service and on-line, being priced around AUD 2000 +GST ready to install. Using patented technology the OPTImizer+ monitors critical breaker operating characteristics to alert the need for maintenance only when significant problems appear or failure is imminent, reporting by exception. Uniquely, the product is not specific to any one breaker type and can be fitted to any breaker in minutes via a simple split core CT’s and the use of breaker auxiliary contacts.

On-line breaker monitoring provides intelligence about breaker condition so as to employ in turn immediate remedial protection and control schemes for protection from either incipient breaker failures or the possible occurrence of a breaker failing to clear a fault (or to allow restrikes) as a result of defective arc shutes. Employing such schemes offers a way to improve power delivery by predicting such issues, and avoiding breaker failure during fault clearance operations. The suspected breaker may then be examined, refurbished if necessary, and placed back into service. INCON’s offering indeed makes this objective a practical, yet affordable, reality.