(A) Voltage withstand test
(B) Partial discharge scanning tests
(C) Life tests
(D) Impulse testing
Answer:(B) Partial discharge scanning tests
Explanation:
A partial discharge (PD) is an electrical discharge or spark that bridges a small portion of the insulation between two conducting electrodes.
Partial Discharge can happen at any point in the insulation system, where the electric field strength exceeds the breakdown strength of that portion of the insulating material.
Partial Discharge can occur across the surface of insulating material (mainly due to contaminants or irregularities), within gas bubbles in liquid insulation, in voids within solid insulation or around an electrode in gas (corona activity).
Partial discharge scanning tests:
85% of disruptive failures in high voltage (HV) and medium voltage (MV) equipment are Partial Discharge related.
Partial Discharge action ultimately leads to failure.
PD testing service does not require shutdown and is the best way to plan maintenance, repair, or replacement activities in a cost-effective and efficient way.
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