Capacitive voltage transformers isolate the measuring instruments, meters, relays, protections, etc., from the high voltage power circuit and provide a scaled replica of the voltage in the HV line. They enable transmission of high frequency signals through the high voltage (HV) lines. Coupling Capacitors are only used for coupling high frequency communication signals, making them equivalent to the capacitive part of a CVT.
Inductive voltage transformers are designed to provide a scaled down replica of the voltage in the HV line and isolate the measuring instruments, meters, relays, etc., from the high voltage power circuit.
Combined Instrument Transformers contain a current transformer and an inductive voltage transformer within the same body. Thus they are used in the same applications as their respective independent transformers; they separate meters, counters, relays, etc., from the high voltage circuit, and provide a scaled replica of the current and voltage in the HV line.
