Current Transformers Quiz

What is the primary purpose of an instrument transformer?

• To increase power in a system

• To transfer energy between circuits without voltage/current changes

• To step down high voltage and current for measurement and safety

• To operate only in DC circuits

What are the two main types of instrument transformers?

• Power Transformer and Auto Transformer

• Voltage Transformer and Isolation Transformer

• Current Transformer (C.T.) and Potential Transformer (P.T.)

• Distribution Transformer and Power Transformer

In a current transformer, how are the primary and secondary windings connected?

• Primary is parallel, secondary is in series

• Both primary and secondary are in parallel

• Primary is in series with the line, and secondary is connected to an ammeter

• Both primary and secondary are in series

Which of the following is true about the windings of a current transformer?

• Primary winding has more turns than the secondary winding.

• Secondary winding has more turns than the primary winding.

• Both primary and secondary windings have equal turns.

• The number of turns does not affect the transformer’s operation.

What happens to the secondary current in a current transformer when the secondary voltage increases by X times?

• Secondary current decreases by X times.

• Secondary current increases by X times.

• Secondary current remains unchanged.

• Secondary current becomes zero.

What is one major limitation of instrument transformers?

• They can only measure voltage and not current.

• They work only with AC circuits and not with DC circuits.

• They do not ensure operator safety.

• They cannot operate protection devices like relays.

How do instrument transformers ensure safety during measurement?

• By using only high-range meters

• By stepping down high voltage and current to manageable levels

• By operating only in low-power systems

• By isolating the primary circuit completely

Which of the following is NOT an advantage of instrument transformers?

• They make equipment handling easier.

• They allow the use of low-range meters for high-voltage systems.

• They operate efficiently in both AC and DC circuits.

• They can be used to operate protective devices like relays.

What happens to energy in a current transformer?

• It decreases with a decrease in current.

• It remains constant while stepping down current and stepping up voltage.

• It increases with an increase in voltage.

• It depends on the type of connected load.

Why are the ratings of low-range meters fixed when used with instrument transformers?

• To match the voltage level of the system

• To handle variable high voltage and current levels

• To standardize measurement, irrespective of high voltage or current

• To prevent saturation in the primary winding