In DC series motor field coils or winding will be in series with the armature winding. The conductor size of the field winding will be having a thick wire (large cross section) with lesser turns.
Advantages of DC Series Motors
The main application where series motors are best suited is for traction applications. The torque of the series motor is proportional to the square of the field current (T α I2field). Therefore Starting torque for the series motor is quite high. Because of this property series motors are widely used in electric traction and in crane applications.
Disadvantages of DC Series Motor
- Speed regulation in the series motor is quite poor. With the increase in the load speed of the machine decreases. (DC shunt motor maintains almost constant speed from no load to full load).
- With decrease in the speed torque of the dc series motor drops sharply
- DC series motor should always require to be loaded before starting the motor. Therefore series motors are not suited for the applications where the load on the motor is completely removed and where motors are driving the belts. Mishap to the belt leads to motor operate on no load and attains dangerous speeds which damage the motor.