Which instrument is representing an integrating type instrument? 

An energy meter is a type of integrating instrument.

Types of measuring instruments

The measuring instruments are divided into four major parts:

1.) Indicating Instrument

• The indicating Instrument displays only the value of the electrical quantities per time of measurement.
• This instrument gives the reading only when connected to the electrical supply. Otherwise, it goes to the zero position.
• Ammeters, Voltmeters, Wattmeters, etc are examples of indicating instruments.

2.) Recording Instrument

• The recording Instrument displays and records the reading of the electrical quantities per time of measurement.
• This instrument is generally used in the generating Station and substation.
• ECG and X-Rays are examples of recording instruments.

3.) Integrating Instrument

• The Integrating Instrument displays, record, and add the numerical value of the reading of the electrical quantities per time of measurement.
• The energy meter and Ampere-hour meter are examples of integrating instruments.

4.) Null Deflection Instrument

• The Null Deflection Instrument shows the reading of the electrical quantities without the deflection angle at per time of measurement.
• The potentiometer is an example of a null deflection instrument.