## electrician

### MCQ ON MEASURING INSTRUMENT PAGE - 4

1.
 Normally the scale of moving iron instruments will be … A Initially crowded, gradually widen scale B Initially widen, gradually crowed scale C Have a uniform graduated scale D Have a un-uniform graded scale Answer : D Explanation :
2.
 Moving iron instruments are used to measure both A.C and D.C quantities. What will happen if the terminals of a moving iron instrument are interchanged in D.C circuit? A It will give no deflection B It will indicate the same reading C It will givefull scale deflection D It will deflect in the reverse direction. Answer : B Explanation :
3.
 Instruments which must not be used in the circuit, when the power is ON are…. A Wattmeter ad power factor meter B Frequency meter and long tester C Phase sequence mete and energy meter D Ohm meter and megger Answer : D Explanation :
4.
 A house has 4KW connected loads and is fed by single-phase supply What range energy meter is recommended for the house? A 20 amperes B 15 amperes C 30 amperes D 10 amperes Answer : C Explanation :
5.
 In an induction type energy meter, the speed of rotation of the aluminum disc is proportional to the … A Current flowing through the load B Square of the current in the current coil C The voltage applied to the pressure coil D The current in the current coil and voltage in the pressure coil Answer : D Explanation :
6.
 A 3 phase 3  element energy meter of 415 V, 50Hz has its pressure coil rated for… A 230 volts B 240 volts C 415 volts D 440 volts Answer : B Explanation :
7.
 Your are testing an energy meterof 240 volts, 50Hz 5 amperes, 750 revolutions per KWh for its performance with some load. When the disc rotates 100 revolutions in 10 minutes, what is the energy sup A 13.33kWh B 1.33kWh C 0.133kWh D 0.0133 kWh Answer : C Explanation :
8.
 Ammeters used for current measurements in circuits with short overload time] differs from other application Ammeters used I short overload time circuit have.. A Non-linear scale B Extended scale C Linear scale D Fine scale Answer : B Explanation :
9.
 You have to connect an ammeter to monitor the current drawn by a 3-phase, 5HP , 415V, 50 Hz squirrel cage induction in motor, connected through a DOL starter. The range of ammeter, suitable for con A 0 to 30 amperes (extended scale) B 0 to 15 amperes (linear scale) C 0 to 10 amperes (non linear scale) D 0 to 5 amperes(extended scale ) Answer : A Explanation :
10.
 Which type of wattmeter can be used on AC only A Dynamometer type wattmeter B Electrostatic type wattmeter C Induction type wattmeter D Commulator type wattmeter Answer : C Explanation :
11.
 In a dynamometer type wattmeter, the deflecting torque is proportional to … A The square of the current in fixed coil B The current in the moving coil C The current in the fixed coil and in the moving coil D The current in the fixed coil Answer : C Explanation :
12.
 What type of quantity is measured in Ferranti type mercury meter? A DC watt-hour B DC ampere-hour C AC and DC watt-hour D AC watt-hour Answer : B Explanation :
13.
 The reading on a 3 digit milli voltmeter started flashing continuously when connected across a resistor to measure the MV DEOP ACROSS IT. The reason for flashing of display on milli voltmeter is th A The battery in the instrument is weak B There is not battery I the instrument C The measured value is over range D The display is damaged Answer : C Explanation :
14.
 Which one of the following measurement test an not be done with a multimeter? A Current drawn by an electronic circuit B Supply voltage to DC motor C Continuity test of motor ending D Insulating resistance of motor Answer : D Explanation :
15.
 In battery-powered digital multimeter, LCD displayed is most commonly used. The reason for this is A Mains power is not available everywhere B It requires only a small amount of power C LCD can be read even in dark D LCD has a bright displayed Answer : B Explanation :
16.
 The scale of a multimeter is set at the range of 60 V. the percentage of the indicated error is highest in the range of A 0 V to 10V B 20 V to 40 V C 40 V to 50 V D 50 V to 60 V Answer : A Explanation :
17.
 What are the measurements that can be done from a portable digital multimeter without a battery ? A Both voltage and current measurement B Except  resistance all other measurement C Only current measurement D No measurement is possible Answer : D Explanation :
18.
 What are the measurements for which multimeter is suitable without battery? A Voltage . Current and resistance B Voltage and current C Only for resistance D Resistance and voltage Answer : B Explanation :
19.
 On the scale of a power factor meter, the pointer indicates 0.8 leading power factor. This value means that the load is a … A Pure capacitance B High inductive and low capacitive reactance C High resistance and low inductive reactance D Low inductive reactance and high capacitive reactance Answer : D Explanation :