Chapter 4 : AC Machine
... current (ac) than direct current (dc). For this reason, and because ac voltage is induced into the ...
... current (ac) than direct current (dc). For this reason, and because ac voltage is induced into the ...
Synchronous Motors
... When such a machine is connected in parallel with induction motors or other devices that operate at low lagging power factor, the leading kVAR supplied by the synchronous condenser partly neutralizes the lagging reactive kVAR of the loads. Consequently, the power factor of the system is improved. Fi ...
... When such a machine is connected in parallel with induction motors or other devices that operate at low lagging power factor, the leading kVAR supplied by the synchronous condenser partly neutralizes the lagging reactive kVAR of the loads. Consequently, the power factor of the system is improved. Fi ...
starter
... add an additional terminal (N) that links the supply to the no voltage coil. These starters are typically employed in applications where the motor is expected to operate above normal speed. The N terminal is necessary because higher speeds reduce field currents through the F terminal so that the han ...
... add an additional terminal (N) that links the supply to the no voltage coil. These starters are typically employed in applications where the motor is expected to operate above normal speed. The N terminal is necessary because higher speeds reduce field currents through the F terminal so that the han ...
PowerPoint presentation
... field speed • Motor runs a synchronous speed whatever the mechanical load provided rotor field is strong enough ...
... field speed • Motor runs a synchronous speed whatever the mechanical load provided rotor field is strong enough ...
PowerPoint presentation
... field speed • Motor runs a synchronous speed whatever the mechanical load provided rotor field is strong enough ...
... field speed • Motor runs a synchronous speed whatever the mechanical load provided rotor field is strong enough ...
PH I LI PS TECHNICAL REVIEW
... arrangement and the rotating magnet (fig. J), and he published an article on electromagnetic rotations in October 1821. The apparatus was copied and the experirnents repeated all over Europe [41. Peter Barlow, who lectured at the Woolwich Academy, repeated Faraday's rotation experiment and then repl ...
... arrangement and the rotating magnet (fig. J), and he published an article on electromagnetic rotations in October 1821. The apparatus was copied and the experirnents repeated all over Europe [41. Peter Barlow, who lectured at the Woolwich Academy, repeated Faraday's rotation experiment and then repl ...
Question Bank - Saraswathi Velu College of Engineering
... ii) Derive the emf equation of DC Machine, how can its direction be obtained? 2. Explain the open circuit and load characteristics of DC generators? 3. Explain the various types of DC motors with suitable diagram showing the connection of field coils to armature? 4. i) Explain the swinburne’s test t ...
... ii) Derive the emf equation of DC Machine, how can its direction be obtained? 2. Explain the open circuit and load characteristics of DC generators? 3. Explain the various types of DC motors with suitable diagram showing the connection of field coils to armature? 4. i) Explain the swinburne’s test t ...
Section 9.5 Electric Motors
... that they always supply current to at least one coil but not so wide that they directly connect the brushes to one another, the rotor will always start spinning when it’s turned on. The rotor of a DC motor turns at a speed that’s proportional to the voltage drop through its coils. Those coils have l ...
... that they always supply current to at least one coil but not so wide that they directly connect the brushes to one another, the rotor will always start spinning when it’s turned on. The rotor of a DC motor turns at a speed that’s proportional to the voltage drop through its coils. Those coils have l ...
Objective bits
... 17). Delay line is used to delay the signal for some time in the horizontal sections. a)True b)False. 18).If a positive potential is applied to the vertical deflection plates, then the beam on the screen moves upwards.a) True b)False. 19)The voltage which varies linearly with respect to time is appl ...
... 17). Delay line is used to delay the signal for some time in the horizontal sections. a)True b)False. 18).If a positive potential is applied to the vertical deflection plates, then the beam on the screen moves upwards.a) True b)False. 19)The voltage which varies linearly with respect to time is appl ...
2014
... a) Draw a neat sketch of 3- point starter used for a DC motor and explain the protective devices provided in it. b) A 100 kW, 500 V, 750 rpm, D.C shunt generator, connected to constant voltage bus bars, has field and armature resistances of 100Ω and 0.1Ω respectively, and delivers full load. If the ...
... a) Draw a neat sketch of 3- point starter used for a DC motor and explain the protective devices provided in it. b) A 100 kW, 500 V, 750 rpm, D.C shunt generator, connected to constant voltage bus bars, has field and armature resistances of 100Ω and 0.1Ω respectively, and delivers full load. If the ...
GCSE PHYSICS ELECTROMAGNETISM
... (b) A car of mass 1600 kg can be just be lifted. What is the least force that the electromagnet must use to lift the car? ...
... (b) A car of mass 1600 kg can be just be lifted. What is the least force that the electromagnet must use to lift the car? ...
Individual Group Control (IGC) 4N1 Motor Controller
... group control for up to four Somfy® Wired Technology (WT) motors with up to three intermediate positions per motor. Through the use of the DecoFlex Dry Contact Keypad (#1811402, required), users can access 3 preset positions as well as Up, Down and Stop. Keypads can also be used to set custom interm ...
... group control for up to four Somfy® Wired Technology (WT) motors with up to three intermediate positions per motor. Through the use of the DecoFlex Dry Contact Keypad (#1811402, required), users can access 3 preset positions as well as Up, Down and Stop. Keypads can also be used to set custom interm ...
Transformer Protection
... winding designed for (100 -500V) and is loaded with a resistor • Under earth fault conditions a current will flow in the secondary • Over voltage or over current relay could be employed • These could provide only 90-95% of the stator winding. ...
... winding designed for (100 -500V) and is loaded with a resistor • Under earth fault conditions a current will flow in the secondary • Over voltage or over current relay could be employed • These could provide only 90-95% of the stator winding. ...
... wherein four drive motors actuate pairs of orthogonal rollers pressing against the ball to create motion in the plane, while a fifth drive motor provides yaw motion to affect the body azimuth. Second, there is the “tri-wheel” principle [3] wherein three motors drive the ball in all three DOFs using ...
Commutator (electric)
A commutator is the moving part of a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. It consists of a cylinder composed of multiple metal contact segments on the rotating armature of the machine. The commutator is one component of a motor; there are also two or more stationary electrical contacts called ""brushes"" made of a soft conductor like carbon press against the commutator, making sliding contact with successive segments of the commutator as it rotates. The windings (coils of wire) on the armature are connected to the commutator segments. Commutators are used in direct current (DC) machines: dynamos (DC generators) and many DC motors as well as universal motors. In a motor the commutator applies electric current to the windings. By reversing the current direction in the rotating windings each half turn, a steady rotating force (torque) is produced. In a generator the commutator picks off the current generated in the windings, reversing the direction of the current with each half turn, serving as a mechanical rectifier to convert the alternating current from the windings to unidirectional direct current in the external load circuit. The first direct current commutator-type machine, the dynamo, was built by Hippolyte Pixii in 1832, based on a suggestion by André-Marie Ampère. Commutators are relatively inefficient, and also require periodic maintenance such as brush replacement. Therefore, commutated machines are declining in use, being replaced by alternating current (AC) machines, and in recent years by brushless DC motors which use semiconductor switches.