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What else can I help you with?
What is the current in the secondary coil fi the current in the primary coil is 5.0A 10 loops on primary coil and 20 on secondary coil?
If I am not wrong then you have asked about a transformer. And its a current transformer. By theory of voltage transformer we know that Vs/Vp = Ns/Np So for answering your question we need the value of number of turns in primary and secondary coil. But you can use this equation to find your answer if you have other values. By using ohmic law you can convert voltage to current.
What is motoring mode of DC motor?
Read this Part I:DC Motor principles pg 1 Part I: Principles of DC Drive Control Learning Objectives: * to learn the basic characteristics of DC motors and their control parameters * to understand the various operating modes DCmotors and their representation: The basic principle of a DCmotor is the production of a torque as a result of the flux interaction between a "field" produced on the STATOR (either produced by a permanent magnet, or a field winding) and the current circulating in the "armature" windings on the ROTOR. In order to produce a torque of constant sign, the armature winding loops are connected to a set of "brushes" which commutate the current appropriately in each loop according to their geometric position. The commutator is a MECHANICAL RECTIFIER. Note that reversal of either the field current or the armature current results in a torque in the opposite direction. However, reversal of both fields does not change the torque direction, hence it can be used as a "universal motor" with DC or AC feed if both windings are in series. Basic Equations of a DC Machine: Steady state conditions (assume all time varying quantities have a constant average value) ( ) ( ) ( ) ( ) ( ) P T developed power T K I I A B T electrical torque V R I E R I K I armature voltage E K I Counter emf or Back EMF V R I fieldwinding d e e t f a load a a a a a v f v f f f f w w w w = = = + + = + = + = = (The back emf assumes that the magnetizing characteristic, E(If) is linear) Speed control: we can extract: v f a a a K I V - R I w = and one can control the speed with 1) Va "Voltage Control" 2) If "Field Control" 3) Ia (with If fixed) "Demand Torque" In practice, for speeds less than the base speed (rated), the armature current and field currents aremaintained at fixed values (hence constant torque operation), and the armature voltage controls the speed. For speeds higher than the base speed, the armature voltage is maintained at rated value, and the field current is varied to control the speed (note the hyperbolic characteristic). However, N +V (free wheeling diode) Armature Current (Rf, Lf) (La, Ra) Eo Rfc Field Control Resistor Fig 1: DC Motor Part I:DC Motor principles pg 2 this way the power developed Pd is maintained constant. This mode is referred to as "field weakening" operation. Case of Series Motor (or Universal Motor) In this case the field winding is series with the armature winding, hence If and Ia are equal. This leads to: v a a a f a K I V - (R + R )I w = One can either control the armature voltage (Voltage Control), or the armature current (Current Control) which is a measure of the torque control. Td , Pd Torque Power constant torque constant power speed Ia If Fig 2: Control Modes Torque Power constant torque constant power speed Td Ia Fig 3: DC Series Motor Control Part I:DC Motor principles pg 3 OperatingModes of DCMotors: Motoring: The back emf E < Va both Ia and If are positive. The motor develops a torque to meet the load torque. Dynamic Breaking: The voltage source is removed, and the armature is shorted. The kinetic energy stored in the rotor of the motor is dissipated in the armature resistance since the machine now works as a generator. Note here that theoretically, since the armature voltage is proportional to the speed, the motor would never stop... but in fact because there is also friction and viscous friction (windage), the motor will stop as soon as the speed is at a certain low value. Regenerative Breaking: The back emf E > Va , the machine acts as a generator, and the armature current flows towards the source, hence energy stored in the machine rotor is fed back to the source. Note however that this will cause the machine to slow down usually until E=Va and then revert to mode 1. Plugging: Plugging iswhen the field current is reversed, hence the back emf changes sign, and the equation of the machine becomes: a a a V = -E - R I hence a a a R I V E + = which means a very high torque generated in the opposite direction of rotation. Avery powerful breaking takes place. However it must be noted that the armature has to be opened as soon as the motor reaches zero speed, otherwise it will start rotating in the opposite direction. N +Va Rfc (La, Ra) E Ia (Rf, Lf) +Vf If Fig 4: Motoring Forward Tem w rated torque V1 V2 V3 V2 Tload FIG 5 torque speed V2 N +Va Rfc (La, Ra) E (Rf, Lf) +Vf Fig 6: Dynamic Breaking + Ia R V2 N +Va Rfc (La, Ra) E (Rf, Lf) +Vf Fig 7: Regenerative Breaking + Ia Part I:DC Motor principles pg 4 Two Transistor control of regenerative operation When the main switch opens, the armature current I(a1) has to be dissipated through the freewheeling diode. Then if one closes switch T1, the machine behaves as a generator with the energy stored in its inertia. Therefore the armature current I(a2)will start flowing and follws I(1). After a certain time one opens the switch T1, and the current I(a2) has to be redirected via diode D2 back to the source with I(2). This is because of the inductance of the machine acts as an emf restoring the flux stored in the magnetic field. Then one closes T1 again and so on. The chopping rate of switch T1 can be set in order to control the average current (Ia2), usually 1.5 times rated value. This is possible only if the speed is fast enough to provide terminal voltage. When the emf E reaches E=Ra.I(rated), the switch T1 remains closed for maximum breaking possible with the given emf. Four Quadrant Operation: Figure 8 summarizes the modes of operation in a four quadrant representation. Torque Speed Forward MOTORING Forward BREAKING Reverse BREAKING Reverse MOTORING Fig 8: 4 quadrant operation V2 N +Va (La, Ra) E Fig 7: Regenerative Control + T1 i2 i1 ia1 ia2 average Ia
What happen if the number of loops in the primary and secondary coils in a transformer are the same?
If the number of turns in the primary is the same as the secondary, this would be an isolation transformer. Primary and secondary voltages should match (minus the inherent transformer losses), as should the current.
How can transistors act as amplifiers or switches?
by creating two circuit loops
What are the application of differential compound generator?
Differential compounded generators are used in Ward Lenard motor generator loops. The shunt fields on these generators are separately excited and when the shunt field polarity is reversed by the controller the series field helps drive the generator voltage to zero thus aiding in the reversal of current.
Loops of wire that turn in the magnetic field of an armature create?
alternating current
What The distance that the pointer of a galvanometer moves depends on the amount of magnetism in the loops of the armature?
The distance that the pointer of a galvanometer moves is determined by the strength of the magnetic field present in the coils or loops of the armature. When an electric current flows through the coils, it interacts with the magnetic field produced by the coils, resulting in a deflection of the pointer. The greater the magnetism in the loops, the larger the deflection of the pointer.
Is it true or false several loops of wire wrapped around an iron core form the armature of a motor?
True. Several loops of wire wrapped around an iron core create the armature of a motor. This configuration helps to produce a magnetic field when current flows through the wire, allowing the motor to convert electrical energy into mechanical energy for motion.
What happens as you increasse and decrease the number of loops in an electromagnet?
Increasing the number of loops in an electromagnet strengthens the magnetic field produced, resulting in a stronger electromagnet. Conversely, decreasing the number of loops weakens the magnetic field, making the electromagnet less strong.
What is a long coil of wire with many loops?
armature
Will increasing the number of loops in a solenoid cause the strength of its magnetic field to decrease?
No, increasing the number of loops in a solenoid will actually increase the strength of its magnetic field. This is because more loops increase the amount of current flowing through the coil, which in turn increases the magnetic field produced.
What is the current ring theory of magnetism?
The current ring theory of magnetism suggests that magnetic materials possess microscopic "current loops" created by the movement of electrons within the material. These current loops produce magnetic fields and are responsible for the magnetic properties observed in materials.
The direction of a magnetic field produced by an electric current depends on the direction of the what?
The direction of a magnetic field produced by an electric current depends on the direction of the current flow. The magnetic field will form circular loops around the current-carrying wire, following the right-hand rule.
Why the magnetic field strength of an electromagnet be reduced in decrease the number of loops in the coil?
Reducing the number of loops in the coil decreases the amount of current flowing through the electromagnet, leading to a weaker magnetic field strength. The strength of the magnetic field produced by an electromagnet is directly proportional to the number of turns of wire in the coil, so fewer loops result in a weaker overall magnetic field.
What component is made of loops of wire that rotate in the magnetic field provided by the field poles and field coils?
An armature is the component that is made of loops of wire that rotate in the magnetic field provided by the field poles and field coils. This rotation induces an electromotive force and generates electrical energy in devices such as generators and alternators.
What is a current-carrying coil of wires with many loops?
solenoid
Would increase the strength of an electromagnet?
More coils of wire around the magnetic material.More current through the wire in the coil.Increasing the current flowing through the wire Increasing the number of loops of wireputting a piece of iron inside the loops of wire apex :)Increasing the current flowing through the wireIncreasing the number of loops of wire
