What function do instrument transformers serve_______________?
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Answer: C. both A. and B.
Explanation
Instrument transformers encompass both potential transformers and current transformers used in power systems. Potential transformers step down high voltages to safe levels for standard measuring instrument connections. Current transformers reduce massive line currents proportionally so standard ammeters can monitor them safely. Instrument transformers isolate sensitive low voltage meters from high voltage transmission conductors. They provide standardized secondary outputs typically rated at one hundred twenty volts or five amperes. Accurate transformation ratios ensure that secondary meter readings precisely reflect primary system conditions.
Power substations rely entirely on instrument transformers to feed protection relays and metering equipment. High voltage grid monitoring would be impossible without instrument transformers stepping down electrical levels. Engineers must account for ratio and phase errors in instrument transformers during high accuracy testing. Option A only names potential transformers while omitting current monitoring transformer devices. Option B only lists current transformers while ignoring high voltage potential transformer equipment. Option D power transformers are designed for bulk energy transfer rather than measurement isolation.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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