157551. The standard secondary voltage for a PT used in power system in :
157552. Which instrument always indicates true r.m.s. value irrespective of the waveform?
157553. A voltmeter gives inaccurate reading to measure the drop across a low resistance because :
157554. The phase difference between the currents in the two pressure coils in PF meter is :
157555. When a rewound armature is rolled on the surface of a leveled surface plate the armature stops at the same position of its periphery for each rolling, the portion of armature touching the surface plate is regarded to have :
157556. Which one of the follow ing characteristic is NOT applicable to synchronous motors?
157557. The colour of light depends upon :
157558. Which of the following lamp is a cold cathode lamp?
157559. You have to repair storage type water heater which has steam in the hot water. The possible remedy for this trouble can be found by checking :
157560. The reading on a 3 digit millivoltmeter started flashing continuously when connected across a resistor to measure the mV across it. The reason for flashing of display on millivoltmeter is that:
157561. Shunts and multipliers used in MC instruments are made up of Mangnin. The reason for using the above metal is that, it has :
157562. In order to operate a fluorescent tube set on DC supply, which of the following additional auxiliary device is to be connected?
157563. The power input increases by three times when the connection of three phase loads changes from star to delta at the same line voltage. What is the reason for this?
157564. In a parallel resonant circuit the capacitor current is :
157565. According to National electric code what is the specified minimum distance between the washing unit and the switch board :
157566. In the output voltage of a DC generator the ripple effects can be reduced by increasing the :
157567. The most economic method of electrical braking is :
157568. When a DC series motor is connected to an AC supply, then :
157569. Dummy coils in a DC generator is provided :
157570. When the number of poles and the number of armature conductors are fixed, then which winding of a DC generator will give the higher e.m.f.?
157571. Earth tester is used for measuring earth resistance in which generated DC is converted into AC by current reverser. The reason for using AC supply for resistance measurement is :
157572. The basic function of voltage stabilizer is to provide :
157573. A food mixture rated for 240 V AC fails to start when it is switched on. Which one of the following is NOT a cause for the above?
157574. In a transformer the leakage flux may he minimized by :
157575. The phase relationship between primary and secondary terminal voltage of a transformer is :
157576. The no load primary current Io in an ideal transformer is :
157577. One of the diode of a bridge rectifier connected to 100 V 50 Hz AC input is found to be damaged. The DC output of the circuit is 90 V. The minimum value of PIV of the diode required for replacement is :
157578. You are working with a fully automatic star delta starter. You notice that when start switch is pressed the motor starts in star but docs not change to delta. The trouble will be in :
157579. Watt-hour meter is classified ns a :
157580. During no load test of a 3 phase induction motor, the motor draws power :
157581. The recent method of smooth speed control of a three-phase induction motor over a wide range is :
157582. Rotor bars of squirrel cage rotor are sometimes skewed :
157583. For 66 kV lines the number of insulator discs used is :
157584. AC resistance of a line conductor is more than its DC resistance because of:
157585. The back emf set up in the armature of a synchronous motor depends on :
157586. The current drawn by an over excited synchronous motor will be :
157587. Two alternators are sharing an inductive toad equally. What will be happened if the excitation of one alternator is increased?
157588. A ceiling fan rotates slowly in either direction. The probable fault is :
157589. In repulsion motor, maximum torque is developed when :