GATE EE

Electrical and Electronics Measurement

Basic of Indicating Instruments

Previous Years Questions

## Marks 1

Two balanced three-phase loads, as shown in the figure, are connected to a $$100\sqrt 3 $$ V, three-phase, 50 Hz main supply. Given Z1 = (18 + j24) $$...

Match the following.
...

A ($$0-50$$ $$A$$) moving coil ammeter has a voltage drop of $$0.1$$ $$V$$ across its terminals at full scale deflection. The external shunt resistanc...

The saw-tooth voltage waveform shown in the figure is fed to a moving iron voltmeter. Its reading would be close to _______.
...

The input impedance of the permanent magnet moving coil $$(PMMC)$$ voltmeter is infinite. Assuming that the diode shown in the figure below is ideal, ...

Three moving iron type voltmeters are connected as shown below. Voltmeter readings are $$V,$$ $${V_1}$$ and $${V_2}$$ , as indicated. The correct rela...

A periodic voltage waveform observed on an oscilloscope across a load is shown. A permanent magnet moving coil $$(PMMC)$$ meter connected across the s...

An ammeter has a current range of $$0$$-$$5A,$$ and its internal resistance is $$0.2\Omega $$. In order to change the range to $$0$$-$$25$$ $$A$$ we n...

A $$PMMC$$ voltmeter is connected across a series combination of a $$DC$$ voltage source $${V_1} = 2V$$ and $$AC$$ voltage source $${V_2}\left( t \rig...

A galvanometer with a full scale current of $$10$$ $$mA$$ has a resistance of $$1000$$$$\Omega $$. The multiplying power (the ratio of measured curren...

The effect of stray magnetic fields on the actuating torque of a portable instrument is maximum when the operating field of the instrument and the str...

A Manganin swamping resistance is connected in series with a moving coil ammeter consisting of a milli-ammeter and a suitable shunt in order to

A d.c. voltmeter has a sensitivity of $$1000$$$$\Omega /volt.$$ When it measures half full scale in $$100$$ $$V$$ range, the current through the voltm...

A moving coil galvanometer is made into a d.c. ammeter by connecting

An advantage of a permanent magnet moving coil instrument is that it is

The scale of a voltmeter is uniform. Its type is

For a given frequency, the deflecting torque of an induction ammeter is directly proportional to

Four ammeters $$M1, M2, M3$$ and $$M4$$ with the following specifications are available.
A current of $$1$$ $$A$$ is to be measured. To obtain mini...

Two $$100V$$ full scale $$PMMC$$ type D.C voltmeter having figure of merits ($$FOM)$$ of $$10k\Omega /V$$ and $$20k\Omega /V$$ are connected in series...

A $$0$$-$$10$$ $$mA$$ $$PMMC$$ ammeter reads $$4$$ $$mA$$ in a circuit. Its bottom control spring snaps suddenly. The meter will now read nearly

An unshielded moving iron voltmeter is used to measure the voltage in an a.c. circuit. If a stray d.c. magnetic field having a component along the axi...

The current $$i(t)$$ passing through $$10\Omega $$ resistor as shown in fig $$A$$. as a waveform as shown in fig $$B.$$ Then the reading of the d.c ...

## Marks 2

A 0-1 Ampere moving iron ammeter has an internal resistance of 50 m$$\Omega $$ and inductance of
0.1 mH. A shunt coil is connected to extend its range...

A dc voltage with ripple is given by $$v\left( t \right)\,\,\,\, = \,\,\,\,\left[ {100 + 10\sin \left( {\omega t} \right) - 5\sin \left( {3\omega t} \...

A periodic waveform observed across a load is represented by
$$$V\left( t \right) = \left\{ {\matrix{
{1 + \sin \,\omega t} & {0 \le \omega t ...

Two ammeters $$X$$ and $$Y$$ have resistances of $$1.2$$ $$\Omega $$ and $$1.5$$ $$\Omega $$ respectively and they give full-scale deflection with $$1...

The reading of voltmeter $$(rms)$$ in volts, for the circuit shown in the figure is ______.
...

The dc current flowing in a circuit is measured by two ammeters, one PMMC and another electrodynamometer type, connected in series. The PMMC meter con...

An analog voltmeter uses external multiplier settings. With a multiplier setting of $$20\,\,k\Omega ,$$ it reads $$440$$ $$V$$ and with a multiplier s...

An average-reading digital multimeter reads $$10V$$ when fed with a triangular wave, symmetric about the time axis. For the same input an rms reading ...

A current of $$ - 8 + 6\sqrt 2 \left( {\sin \,\omega t + {{30}^0}} \right)\,\,A$$ is passed though three meters. They are a center zero $$PMMC$$ meter...

A $$1000$$ $$V$$ $$DC$$ supply has two $$1-core$$ cables as its positive and negative leads: their insulation resistances to earth are $$4\,\,M\Omega ...

A DC ammeter has a resistance of $$0.1$$$$\Omega $$ and its current range is $$0$$ – $$100A.$$ If the range is to be extended to $$0$$ –$$500A,$$ the ...

A moving coil of a meter has $$100$$ turns, and a length and depth of $$10$$ $$mm$$ and $$20$$ $$mm$$ respectively. It is positioned in a uniform radi...

A moving iron ammeter produces a full scale torque of $$240$$ $$\,\mu Nm$$ with a deflection of $${120^ \circ }$$ at a current of $$10$$ $$A$$. The ra...

The inductance of a certain moving-iron ammeter is expressed as $$L = 10 + 3\theta - {{{\theta ^2}} \over 4}\mu H,\,\,$$ where $$\,\,\theta \,\,\,$$ ...

An ac voltmeter uses the circuit shown below, where the $$PMMC$$ meter has an internal resistance of $$100$$$$\Omega $$ and requires a dc current of $...

A $$100$$ $$\mu A$$ ammeter has an internal resistance of $$100\,\Omega $$. For extending its range to measure $$500$$ $$\mu A$$, the shunt required i...

A current of $$\left[ {2 + \sqrt 2 \sin \left( {314t + 30} \right) + 2\sqrt 2 \cos \left( {952t + 45} \right)} \right]$$ is measured with a thermocoup...

## Marks 5

For the given circuit the internal resistance of the ammeters as well as that of the current coil of the wattmeter are zero, and the voltmeters have a...