Why DC motor is started on no load?

As from Speed Equation Speed is inversely proportional to flux and for no load or less load the flux produced is also less hence the rotor rotates at very high speed which can damage the motor mechanically. This is the reason why series motor should never be started on light loads or no load conditions.

What happens when DC shunt motor is started with load?

When a load is applied to a DC shunt motor, its speed decreases, but the motor is able to self-regulate and quickly compensate for the lost speed.

Can we start DC shunt and DC series motor without load?

Since speed is constant and torque (τ) is proportional to armature current (Ia). So that, starting a shunt motor at a heavy load requires a high starting current. In order to avoid this high starting current, shunt motors are not started at heavy loads and they should be started without any load.

Which motor should not be started without load or light load?

A series motor should never be started at no load. With no mechanical load on the series motor, the current is low, the counter-EMF produced by the field winding is weak, and so the armature must turn faster to produce sufficient counter-EMF to balance the supply voltage. The motor can be damaged by overspeed.

Why a series motor should not be started without any load?

Which DC motor should not be started on no load?

If it is started without load the field current will be less, hence flux will be less and due to this motor speed will go infinite and damages itself. This is the reason why series motor should not be started without load and shunt motor can be started without load. , Made my first DC motor at age of 7.

Which motor can not be started on no load?

As field current is zero so field flux becomes zero. As speed of a motor is inversly proportional to field flux, so speed tends to infinity i.e, the case if dangerously high speed of DC SERIES MOTOR at no-load.

Which can be started on no load Unlike DC series motor?

Unlike DC series motor, DC compound motor can be started on no-load. Explanation: Cumulative motor takes best from shunt motor and series motor as well. Due to shunt field flux component, DC cumulative motor can be started on no load.

What will happen if the DC shunt motor field winding opened accidentally running on no load?

What will happen if the d.c. shunt motor opened accidentally running on no-load has its shunt field winding? The field will be reduced to only to the value of residual flux. The parts of motor may even fly apart.

Why a DC series motor should not be started without load Mcq?

at no load, it will rotate at dangerously high speed. at no load, it will rotate at dangerously high speed. …