0
What else can I help you with?
Why is dc current used in the excitation of generator?
The field current is used for the excitation of generators.AnswerYou use DC current, because you want the resulting magnetic field to be constant. If you used AC, the resulting magnetic field would vary in both strength and direction.
How do you differentiat dc motior and ac motor physicaly?
if you power an ac motor with dc or a dc motor with ac you will likely start smelling smoke and the motor will be damaged. If the motor is marked "3-phase", "shaded pole", or "induction" it is an ac motor! BTW, there are ac/dc motors that will run on both, they are wound very much like dc motors but a bit differently.
Can you convert a DC motor to run on AC?
The easiest way would be to convert the AC power to DC by using a rectifier diode and a filter capacitor. In that way you can now run your DC motor on DC.
Why a DC motor is called DC motor?
DC, in DC motor, is an acronym for Direct Current, which means that it works on direct electrical supply by a battery. In an AC motor, the motor runs on Alternating Current Supply from other sources other than batteries, such as electricity from your house.No, d.c. is not an acronym. It is simply an abbreviation."a word formed from the initial letters or syllables taken from a group of words"http://www.thefreedictionary.com/acronymYes, a word. "dc" is not a word.
What would cause a meter to read negative voltage across a DC motor?
A DC motor generates power when it is rotating even when no supply is connected.
Is reluctance motor is a synchronous motor with dc excitation?
yes
How do you cut off the excitation of a dc motor?
short leads
Why you have to connect DC supply to the induction motor?
To start an induction motor we have to excite field. The excitation is done by connecting the DC supply to the field winding's.
Give 5 types excitation of DC motor?
there are 2 different types f excitation 1 seperately excited 2 self excited
How the DC generator are classified according to field excitation?
on the basis of field excitation, dc generators are classified into the following types:-1- separetly excited dc generators2-self excited dc generatorsthe behaviour of a dc generator on load depends upon the method of field excitation adopted
Does a induction motor need excitation?
The induction motor is the special kind of motor which runs below and above the synchronous speed. which the synchronous motor runs nearly equal the synchronous speed. The operation of synchronous motor runs with dc field excited hence separate dc field current is given to the field circuit. where as the induction motor the field and main field is drawn from the same supply hence no excitation is required. But due to this separate starting mechanism has to be required in case of the single phase induction motor.
Why would a dc motor show high amps no voltage and struggle to turn?
The current flowing in a dc motor is determined by (Applied voltage-Motor EMF) divided by armature resistance. The motor emf is a function of the field excitation of the motor and the speed at which the motor turns. When the motor starts, there can be no EMF because motor speed is 0 rpm. Therefore the motor will draw more current. But as the motor begins to speed up, if it has field excitation, it has to build up EMF and the current will drop. So : If the motor shows high amps and no voltage and struggles to turn the possible reasons are: 1. The motor has no excitation - The permanent magnets are weak or the field winding is faulty or the field is not being supplied. 2. The armature winding is faulty - it has shorted windings. This assumes your supply is healthy of course.
How can the field coils of a dc machine be connected with self excitation?
No
Why do you give dc source for separate excitation?
In a separately excited DC motor, the field winding is powered by an external DC source, independent of the armature circuit. This allows for precise control of the motor's speed and torque by varying the field current, which directly influences the magnetic flux. Additionally, using a separate DC source enhances the motor's performance and efficiency, as it can be optimized for specific applications without being limited by the armature's current.
Which excitation synchronous motor drawn reactive power?
Hi, Under excitation - inductive reactive power Over excitation - Capacitive reactive power.
Why The Excitation current is non-sinusoidal when applied voltage is sinusoidal?
excitation voltage is sinusoidal because it is taken from the terminal of alternator but excitation current is non-sinusoidal because it always dc.
Why do you give DC excitation to AC Synchronous motor?
If the synchronous motor is running near synchronous speed, it will begin rotating at synchronous speed when DC is applied to the rotor. Source: Electrical Machines, Drives, and Power Systems Theodore Wildi Section 17.3
