How do you calculate the no load speed of a DC motor?

By multiplying the velocity constant by the nominal motor voltage, obtain the theoretical no-load speed of the motor (zero torque and no-load speed) and plot it on the left vertical axis. Draw a straight line between this point and the stall torque and zero speed point on the graph.

What are the applications of DC machine?

Generally, the DC machines are used in supplying excitation of an alternator and it is also used in many applications like welding process, variable-speed motor drives and electrolytic and electroplating process. Small DC machines are used as a control device such as speed sensing, positioning, and tracking.

What are the main parts of DC machines?

Parts of a DC Generator

Stator. The main function of the stator is to provide magnetic fields where the coil spins.
Rotor. A rotor in a DC machine includes slotted iron laminations with slots that are stacked to shape a cylindrical armature core.
Armature Windings.
Yoke.
Poles.
Pole Shoe.
Commutator.
Brushes.

What is the most important part of the DC machine?

commutator

What are the characteristics of DC shunt motor?

Characteristics of a DC Shunt Motor:

Speed-Armature Current Characteristic:
Torque-Armature Current Characteristic:
Speed-Torque Characteristic:
Break in Field Circuit of a DC Motor:

Why DC shunt motor is constant speed?

In a shunt motor, the shunt field current Ish is always a constant since the field winding is connected in parallel to the armature winding and the supply voltage. If load change is not considered since a DC shunt motor has a constant flux φ and a constant supply voltage the speed of the motor remains constant.

What will happen when DC shunt motor is started with load?

Answer : Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease. Answer : With the increase in load on a d.c. shunt motor, speed of the motor reduces slightly.

What are the aims of performing a load test on DC shunt motor?

AIM : To perform load test on a DC series generator and to draw the internal and external (Performance) characteristics . saturation of the machine iron & rapidly increasing voltage drop of armature and armature resistance.

Why DC shunt motor is started on no load?

For DC shunt motor the field resistance is high and armature resistance is low so the variation of flux is very less when rated voltage is applied to the motor and motor speed does not exceeds rated speed at no load. So we can start the DC shunt motor with no load.

Which is the constant speed motor?

DC shunt motor

Why DC shunt motor is used in lathe?

The shunt motors are used where constant speed is required and starting conditions are not severe. The various applications of DC shunt motor are in Lathe Machines, Centrifugal Pumps, Fans, Blowers, Conveyors, Lifts, Weaving Machine, Spinning machines, etc.

What are the application of DC series and shunt motor?

How do you use a DC shunt motor?

A DC shunt motor (also known as a shunt wound DC motor) is a type of self-excited DC motor where the field windings are shunted to or are connected in parallel to the armature winding of the motor. Since they are connected in parallel, the armature and field windings are exposed to the same supply voltage.

How do you control the speed of a DC shunt motor?

Thus, there are three general methods of speed control of D.C. Motors.

Resistance variation in the armature circuit: This method is called armature resistance control or Rheostat control.
Variation of field flux Ф This method is called field flux control.
Variation of the applied voltage.

Which power is mentioned on a nameplate of a motor?

Which power is mentioned on a name plate of a motor? Explanation: Name plate of the motor shows rated values i.e. rated speed, rated current, rated voltage. It also shows output power available at shaft when all other quantities are set to rated values.