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Which of the following is not an integrating instrument?
DC Ampere-hour meter
Watt-hour meter
Voltmeter
All of the above
All of the above
Quick Summary: An integrating instrument records the total quantity of electricity or energy consumed over a specified period by accumulating the instantaneous values. While energy meters (Watt-hour and Ampere-hour) are integrating, a Voltmeter is an indicating instrument that displays instantaneous magnitude, making the original question and provided 'correct' answer (D) technically inconsistent as A and B are integrating.
An integrating instrument records the total quantity of electricity or energy consumed over a specified period by accumulating the instantaneous values. While energy meters (Watt-hour and Ampere-hour) are integrating, a Voltmeter is an indicating instrument that displays instantaneous magnitude, making the original question and provided 'correct' answer (D) technically inconsistent as A and B are integrating.
E=∫0tPdt — Represents total Energy consumed
Q=∫0tIdt — Represents total Charge transferred
Integrating instruments utilize an electromechanical system where the deflecting torque is proportional to the quantity to be measured, driving a counting mechanism (gear train). The total displacement (rotation) is proportional to the time integral of the quantity, expressed as Q=∫t1t2x(t)dt. Indicating instruments, like voltmeters, use a control mechanism (spring) to balance the deflecting torque, resulting in a steady-state pointer position proportional to instantaneous magnitude.
Indicating instruments display the instantaneous value of a quantity.
Integrating instruments totalize the quantity over a specific interval of time.
Watt-hour and Ampere-hour meters are classic examples of integrating instruments.
Voltmeters, Ammeters, and Wattmeters are primarily indicating instruments.
Integrating instruments provide total energy consumption for billing.
Indicating instruments provide real-time monitoring of electrical variables.
Integrating instruments do not provide instantaneous readings.
Indicating instruments require continuous observation to record trends.
Energy billing (Electricity meters)
Industrial power consumption tracking
Real-time voltage monitoring
| Feature | Integrating | Indicating |
|---|---|---|
Function | Accumulation over time | Instantaneous display |
The question statement in the prompt contains a logical error: DC Ampere-hour and Watt-hour meters are indeed integrating instruments. The only non-integrating instrument listed is the Voltmeter.
Standard Classification: Absolute, Indicating, Recording, and Integrating.
The provided option D is logically incorrect as A and B are integrating instruments; the only non-integrating instrument listed is the Voltmeter (Option C).
Always categorize instruments by function: Indicating (pointer), Recording (pen on chart), and Integrating (counting mechanism) to quickly rule out options in exams.