This TechTalk serves as an inspection and routine testing guide for switchgear, switchboard assemblies, and their associated components. It supports a predictive maintenance strategy.
On-line condition assessment method | Component in operation at system voltage and operating temperature under mechanical and electrical stresses.
Electrical discharges (ED) in MV switchgear circuits are (1) Partial Discharges (PD) and (2) Partial Arcing (PA). The breakdown does not bridge the electrodes. i.e. Voids, cracks, contamination etc.
Medium voltage circuit breakers have, over recent years, seen very significant developments in both their operating function and also in the monitoring aspects of their condition.
One of the major sources of problems with circuit breakers is that caused by the deterioration of the main switching electrical contacts. The contacts in switchgear are required to provide two main functions that are mutually incompatible.
Electrical discharges (ED) in MV power circuits are (1) Partial Discharges (PD) and (2) Partial Arcing (PA).
Silicon rubber vermin guards were added to seal the top part of the bushing assembly against vermin ingress.
Vacuum interrupters are used to interrupt medium voltage AC current. Depending on the construction of the vacuum circuit breaker, the bellow allows the movable contact to move while maintaining vacuum.
Condition-based assessments and monitoring form an integral part of the maintenance strategy for medium voltage switchgear.
Failure of electrical switchgear can cause death, severe injury and significant damage. Switchgear failure is rare, but when it occurs, the results can be catastrophic.