# A moving iron ammeter may be compensated for frequency errors by

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A moving iron ammeter may be compensated for frequency errors by shunt capacitance.

## Related questions

Eddy current damping cannot be used for moving iron instrument because

Measurement of power by voltmeter and ammeter method in a circuit resulted in calculated maximum errors of ±1 % and ± 2 %, respectively. The likely error in calculated power is (A) ± 3 % (B) ± 0.022 % (C) ± 1.5 % (D) ± 0.22 %

Moving iron instruments can be used for measuring (1) Direct currents and voltages (2) Radio frequency currents (3) A.C currents and voltages (4) Both (a) and (c)

The measurement range of an ammeter can be increased by using a:

A 150 V moving iron voltmeter of accuracy class 1.0 reads 75 V when used in a circuit under a standard conditions. The maximum possible percentage error in the reading is:

A permanent magnet moving coil ammeter has a coil resistance of 99 ohm and Full Scale Deflection (FSD) current of 0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5 F.S.D is:

If a line is 100 % series compensated it may result into series resonance at power frequency of?

The moving iron voltmeter indicates (a) the same value for dc and ac voltages. (b) lower values for ac voltage than for corresponding dc voltage. (c) higher value for ac voltage than for corresponding dc voltage. (d) none of these.

Two voltmeters of same range, one moving iron type and other permanent magnet moving coil type, are connected in parallel for measuring a.c. supply voltage. If the reading of MI type is 300V, the reading of PMMC type will be (a) zero (b) higher-than M.I. type (c) lower than M.I. type (d) same

Horizontally mounted moving iron instruments use   (a) Eddy current damping (b) Electromagnetic damping (c) Fluid friction damping (d) Air friction damping

An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be  (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field

A compensated wattmeter has its reading corrected for error due to (a) Frequency (b) Friction (c) Power consumed in current coil (d) Power consumed in pressure coil

In moving iron instruments, eddy current damping cannot be used as  (a) They have a strong operating magnetic, field (b) They are not normally used in vertical position (c) They need a large damping force, which can only be provided by air friction (d) The introduction of a permanent magnet required for eddy current damping would distort the existing weak operating magnetic field

A compact microstrip antenna may be obtained by

Leakage fluxes in a transformer may be minimized by : (A) Avoiding overloads (B) Keeping magnetizing current minimum (C) Reducing the reluctance of the iron core to minimum (D) Sectionalizing and interleaving the primary and secondary windings

"Any number of current sources in parallel may be replaced by a single current source whose current is the algebraic sum of individual source currents and source resistance is the parallel combination of individual source resistances". The above statement is associated with?

A 10A DC Ammeter has a resistance of 0.1 Ω is to be extended to 50 A, the required shunt wire is A) Manganin wire of 20 m Ω B) Constantan wire of 20 m Ω C) Manganin wire of 25 m Ω D) Constantan wire of 25 m Ω

A Wheatstone bridge cannot be used for precision measurements because errors are introduced into on account of: - a) Resistance of the connecting lead b) Thermoelectric EMFs c) Contact resistance d) all the above

In a d.c. compound generator, ‘flat-compound’ characteristic, required for certain applications, may be obtained by connecting a variable resistance  A) Across the series field B) In series with the series field C) In parallel with the shunt field D) In series with the shunt field

In d.c. choppers, for periodic time T, the output voltage can be controlled by frequency modulation by varying

A moving coli ammeter has a fixed shunt of 0.02 Ω with a coil circuit resistance of R=1 kΩ and needs potential of 0.5 V across it for full scale deflection. Calculate the value of shunt to give full scale deflection when the total current is 10 A. (1) 0.05 Ω (2) 0.005 Ω (3) 0.5 Ω (4) 0.0005 Ω

Errors can be found by outsiders during  (1) A structured walkthrough (2) Alpha testing (3) Beta testing (4) All of these

In an instrument transformer the errors can be reduced by  (A) Using high reluctance core (B) Using small cross sectional area (C) Using low permeability materials (D) Using low reluctance core

Which parameter or quantity may be measured by use of Maxwell's Bridge ? (A) Resistance (B) Capacitance (C) Inductance (D) Frequency

An induction type energy meter is found to run fast. Correction for this error can be made by  (A) Over-load compensation. (B) Voltage compensation. (C) Moving the brake magnet away from the centre of the disc. (D) Moving the brake magnet towards the centre of the disc.

The main sources of Errors in Permanent Magnet moving Coil (PMMC) are due to : - a) weaking of the permanent magnet due to aging at temperature effects b) weaking of spring due to aging and temperature effects c) change of resistance of the moving coil with temperature d) all the above

A linear time -invariant control system with unsatisfactory steady state error is to be compensated. Which is/are the correct type of cascade compensation to be provided ? 1. Lead 2. Lag 3. Lag -lead Select the correct answer using the codes given below : (a) 1 only (b) 2 only (c) 3 only (d) 1, 2 and 3

Clamp on ammeter is used for measurement of:

Permanent magnet moving coil instruments are used for

Consider the following statements with regard to Moving Iron (MI) instruments :  1. These instruments possess high operating torque.  2. These instruments can be used in ac and dc circuits.  3. Power consumption in these instruments is lower for low voltage range.  Which of the above statements are correct ?  (a) 1 and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1, 2 and 3

If a dynamometer wattmeter is connected in an ac circuit, the power indicated by the wattmeter will be (a) volt-ampere product (b) average power (c) peak power (d) instantaneous power