Q4Electronic Measurement & Instrumentation
Question
2 marks
What is difference between CT and PT ?
Answer
CTs step down series currents into a short-circuited burden; PTs step down parallel voltages into an open-circuited burden.
1. Current Transformer (CT): Connected in series with the power line. It steps down high currents. Its secondary is practically short-circuited through a low-impedance ammeter. Operating a CT with an open secondary is dangerous.
2. Potential Transformer (PT): Connected in parallel across the power line. It steps down high voltages. Its secondary is practically open-circuited through a high-impedance voltmeter.