Substation asset life extension
Your substation is a complex hub of high-voltage equipment that works hard every day to power your production. Do you know your critical substation assets? Do you have strategies in place for maintaining them?
Click on the substation components below to learn more about what they do, why they fail, and how you can prolong their reliable life.
Isolator switch
Also called a disconnect switch or disconnector, this component is essentially a substation “off” switch. It isolates the substation from the utility feed and is used for other applications. The isolator installed in air applications can be seen in the open (off) position with a visible gap that ensures a physical distance between the contact points. You’re likely already familiar with the isolator switch because it’s an integral part of the lockout/tagout (LOTO) procedure.
Isolators come in many different shapes and sizes. They can be manually operated, or motor operated locally, remotely, or automatically. Isolators can be standalone components, or they can be coupled directly to other components, such as circuit breakers or grounding switches.
Failure modes
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Insulation breakdown (due to voltage spikes, long-term overvoltage or lightning strikes)
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Operating mechanism wear/malfunction and misalignment
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Insulator wear/malfunction (supports the isolator switch)
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Contact wear or fused contacts
Reliability considerations
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Mechanical and electrical test of operating mechanism
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Alignment checks
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IR scanning for insulators
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Partial discharge (PD) measurements
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Visual inspection
