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Bushes, with reference to DC motors is a brushed DC motor which is a motor that designed to run from a direct current (DC) power source. This type of motor is an internally committed electric motor.
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Why are the brushes of a dc machine always placed at the neutral points?
The function of brush is to collect current from rotating commutator and supplies the current to external stationary load. The brushes of a DC machine are placed at neutral points because the current in the rotating part drops to zero at the neutral point. If brushes are placed in location other than the neutral points, then the current may be switched off and it causes magnetic field and it may also create voltage spikes and arc at brushes.
Why carbon brushes are used in DC machines?
Carbon brushes used in DC machines because carbon is soft material and it does not generate spikes when contact with commutator
What is interpole in dc motors?
the armature current is brought thru the interpole winding near the brushes this shifts the electrical null to reduce arcing with heavy loads there were arrangements with small motors to shift the brush holder rings but the interpole has no moving parts and works under all loading conditions
What is commutation in DC machines?
It is the process of conversion of generated ac voltage into the armature of a dc generator to dc voltage at the terminal of the dc generator by use of pair of brushes and commutator. OR It is the process of conversion of given dc voltage at the terminal of the dc motor to ac voltage in the armature windings in a dc motor by use of pair of brushes and commutator.
What are homopolar motors used for?
Not much, yet. Homopolar motors work on a principle called the Lorentz force law, the same principle that makes a rail gun work. They are the most basic and conceptually simple rotary electric motors possible. You may also see them referred to as Faraday Disks, or unipolar motors. Because they are so simple, they have the potential to be very efficient, but unlike AC (alternating current) induction motors, AC synchronous motors, or DC (direct current) brushless motors (the latter two are essentially the same), they require brushes, and therefore more maintenance. They also tend to work at low voltage and high current, which makes the brushes more lossy. My best guess is the problems with the brushes are why homopolar motors appear to have never found any commercial or military applications. However, a quick search on google will show that the Navy is interested in using them on ships and subs. Because they are the only truly DC motor, they should prove to be quieter than any other electric drive option they are considering. AC motors come with a lot of noise, just ask your washing machine.
Are DVD DC motors and DC motors same?
actually dc motors are of several types in which one of them are 1).brushed 2).brushless ...so the motor present in DVD are the brushless dc motors ...
Why do door motors get burned?
All motors are made up of 2 basic parts, a coil or coils of wire, and two or more magnets. the motors found in cars and car windows contain dc motors that use a pair of brushes to make contact with the coils that in turn drive the magnet. as u continually use the motor, the brushes are worn away due to friction, once the brushs no longer make contact with the commutator (the copper plates where the brushes come in contact with the coils) the door motor with stop working as no current is able to pass through the motor. you either have to get the brushes replaced, or replace the motor entirely
Why are the brushes of a dc machine always placed at the neutral points?
The function of brush is to collect current from rotating commutator and supplies the current to external stationary load. The brushes of a DC machine are placed at neutral points because the current in the rotating part drops to zero at the neutral point. If brushes are placed in location other than the neutral points, then the current may be switched off and it causes magnetic field and it may also create voltage spikes and arc at brushes.
How many brushes do most starter motors have?
Four
Are the fan motors on fanuc ac spindle motors ac or dc?
usually ac 110v even on the dc motors
What is the Need of dc motor?
DC motors are not common in industry. However traction motors are one such main DC motor application. There are many tools, toys, drones, which use DC motors run by batteries.
Does DC motor run at a varying speed?
only shunt dc motors have varaible speed control. compound dc motors do however NT as much, plus they are just a mixture of series and shunt dc motors.
Where do you find dc motors?
Examples of DC electric motors are the starter in your car and the motor in a DC controlled elevator, to name just two.
Why carbon brushes are used in DC machines?
Carbon brushes used in DC machines because carbon is soft material and it does not generate spikes when contact with commutator
What is the best type of DC motor for use with DC?
Basically anything that works with batteries usually works with DC motors, i.g. your hard drive, your cellphone vibrator, toys, etc. Also, even for large motors, the DC motor has the advantage of being easily controlled by input voltage. Induction motors, on the other hand, can use controlled input voltage but they will have to deal wth low torque when the voltage is low. DC motors are used for those little fans in your computer. Also, CD players also use DC motors to spin the discs. DC motors are important where absolute speed control and feedback are necessary. For your household appliances, including fan motors, those are AC motors, cheaper for the industrial strength and more efficient.
Why DC motors and DC generators are commonly known as DC machines?
because the dc motor will act as dc generator as same as dc generator acts as a dc motor .so it is called as dc machines.AnswerBecause generators and motors are machines, and operate on d.c.'A.C. machines' are generators, transformers, and motors which operate on a.c.
who is more efficient dc motor or ac motor and why?
DC motors are generally more efficient than AC motors. DC motors have a lower amount of inertial associated with them, making them more efficient to run.
