Question

When testing the timing of a high-voltage circuit breaker, what is the precise difference between the &#x27;contact parting time&#x27; and the &#x27;arcing time&#x27; in determining the total clearing time of a fault?

Accepted Answer

When a circuit breaker trips to stop a dangerous surge of electricity, it needs to separate its internal metal pieces, called contacts, to break the flow of current. The contact parting time is the duration from when the breaker receives the trip command until those metal pieces physically pull apart. However, electricity is stubborn and can keep jumping across the opening gap in the form of a bright spark, known as an arc. The arcing time is the specific window of time that this spark continues to burn after the contacts have already parted. Think of it like turning off a garden hose by pinching the pipe; the contact parting is when you start to squeeze, while the arcing is the final trickle of water that leaks out before the flow stops completely. You get the total clearing time by adding the contact parting time to the arcing time. The fault is not truly cleared until the arc is fully put out and the electricity has stopped moving through the gap.

When testing the timing of a high-voltage circuit breaker, what is the precise difference between the 'contact parting time' and the 'arcing time' in determining the total clearing time of a fault?

When a circuit breaker trips to stop a dangerous surge of electricity, it needs to separate its internal metal pieces, called contacts, to break the flow of current. The contact parting time is the duration from when the breaker receives the trip command until those metal pieces physicall....

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When testing the timing of a high-voltage circuit breaker, what is the precise difference between the 'contact parting time' and the 'arcing time' in determining the total clearing time of a fault?

When a circuit breaker trips to stop a dangerous surge of electricity, it needs to separate its internal metal pieces, called contacts, to break the flow of current. The contact parting time is the duration from when the breaker receives the trip command until those metal pieces physicall....

Community Answers