The insulation resistance between a transformer's primary and secondary windings should ideally be_____________?
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Answer: D. infinity
Explanation
Primary and secondary windings are electrically isolated from each other inside the transformer. Insulating materials separate the copper conductors to prevent direct electrical contact between circuits. An ideal insulation system prevents any current leakage resulting in infinitely high resistance. Transformers rely on electromagnetic induction rather than direct electrical connection to transfer energy. Insulation resistance is measured using high voltage megohmmeters during routine maintenance checks. Moisture and aging can degrade insulation quality over years of continuous electrical service.
Utilities test insulation resistance periodically to prevent catastrophic electrical short circuits and fires. Infinite resistance ensures user safety on secondary low voltage distribution circuits. Degraded insulation requires immediate reconditioning or replacement of the transformer unit. Zero resistance would indicate a severe short circuit between primary and secondary windings. Ten ohms represents an extremely low resistance that would cause dangerous electrical fault conditions. One thousand ohms is still far too low and signifies compromised winding insulation integrity.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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