in any dc machine changing the polarity of the field will change its direction. here, in series motor, the field is in series with the armature, to which we feed the supply. hence, change the feeding polarity.
Trick question: all motors do if you invert the polarity of input.CommentNot a trick question! In the case of d.c. motors, for example, you have to reverse the polarity to either the field or the armature -not to both. If you reverse it to both, it makes no difference to the direction of rotation! For a three-phase induction motor, you must interchange any two line conductors.
The compound DC motor has the advantage of both, constant speed feature of the shunt motor and the capability to handle high starting torque feature of series motor.
ac machines can run only in one direction but dc machines can run in both the directions depending upon the direction of current flow into it. If we change polarity of input supply we can reverse the direction of motion of dc machineCommentThe above answer isn't altogether true, as it's very easy to change the direction of an AC machine. For example, to change the direction of rotation of a three-phase induction motor, the motor controller interchanges two of the three line conductors.The main difference used to be that the speed of DC machines is easier to control, but that is a thing of the past thanks to developments in electronic motor controllers.
it will run in same direction because flux and armature current both will be changed wih plarity.
Similar to DC permanent magnet motor (which I'm assuming you understand); except the stator is not a permanent magnet but an electromagnet. There are 2 separate coils on the stator, which are connected in series with the brushes and armature: supply ----- stator segment --- brush - armature - brush --- stator segment ----- return Since the stator coil segments are wired in series with the armature, reversing the supply will *not* change the direction of rotation; as both magnetic fields will reverse together. (But a reversing switch affecting only the armature *will* reverse the rotation.) And since the motor will always turn in the same direction independent of the supply polarity, this means it will work equally well from DC or AC; and the supply frequency will not affect the rotation speed.
All motors have the ability to rotate in either direction. The motor has to be connected to additional equipment to make this happen. In a three phase motor a reversing magnetic contactor is used and in single phase motor usually a drum switch is used.
To reverse a series wound motor, you must reverse the direction of the current flowing through both the armature and the field windings. This can be achieved by changing the connections of either the armature leads or the field leads, depending on the motor design.
only synchronous motor
You can't rotate only the inner circle. You can rotate the entire Widdy Board by grabbing it on both sides and moving it in the direction you want to rotate it.
The direction that they rotate does. Storm systems in the northern hemisphere rotate counterclockwise while ones in the southern hemisphere rotate clockwise. Tropical systems in both hemispheres tend to travel westward.
Two gears rotate in the same direction when they are both either on the same side of the gear train (parallel arrangement) or they have the same number of teeth. They rotate in the opposite direction when one gear is driving another gear and they have a different number of teeth.
both direction moving machine
A single phase induction motor has two sets of coils and a centrifugal start switch. The start winding is in series with the start switch. The start winding provides a rotating magnetic field in one direction enabling the motor to start. The motor can be reversed by reversing the connections of either the start winding or the run winding but not both.
A series DC motor can be thought of as having two components, the rotor and the stator. The rotor has windings which rotate and the stator's windings stay stationary. In a series DC motor these windings are connected in series. To make the motor turn backwards you must reverse the current through either the rotor or stator windings, but not both.
A split phase induction motor has two sets of coils and a centrifugal start switch. The start winding is in series with the start switch. The start winding provides a rotating magnetic field in one direction enabling the motor to start. The motor can be reversed by reversing the connections of either the start winding or the run winding but not both.
Both Venus and Uranus have retrograde, i.e. clockwise, rotation.
yes.because the direction of motor is same in both half cycles