Table of Contents

## What is efficiency of DC shunt motor?

The value of the efficiency of a DC motor could typically be in the range of 70 to 85%. Larger the machine higher will be the efficiency. Losses consist of Armature and field copper losses, core loss, friction and windage loss.

**How is DC motor efficiency measured?**

- You can measure the efficiency of a DC motor by conducting a load test on DC motor.
- Calculate the output power by the formula (2*pi*N*T) / 60 and input power by V*Ioad current.
- The above will give u the efficiency.
- The experimental set up is in the photo.

### How do you read a DC motor performance curve?

On a dc motor / gear motor performance curve, torque is usually represented by the X-axis. The intersection of the speed line (N) and the X-axis is the stall torque (T) point. This is where the motor produces its maximum torque and can no longer rotate.

**What is the condition for maximum efficiency of a DC shunt generator?**

The efficiency of a DC generator is maximum when those losses proportional to the square of the load current. Variable losses are equal to the constant losses of the DC generator i.e. armature circuit loss is equal to the sum of no-load rotational loss and field circuit loss.

## What is DC machine efficiency?

The motors are normally designed to have maximum efficiency while working at or near full load. The efficiency of a dc motor at normal operating conditions may be as high as 95%. A typical efficiency curve showing the manner in which the efficiency varies with the output is shown in Fig.

**How is torque measured in DC motor?**

How to measure torque of a motor? A relatively simple method to estimate electrical motor torque (AC – Synchronous or Induction; or DC – Brushed or Brushless) is to measure its electrical power input, the voltage and the current in the power line driving the motor.

### What is torque in a DC motor?

The torque is defined as the turning moment of a force about an axis. It is measure by the product of the force (F) and perpendicular distance (r) of the line of action of force from the axis of rotation, i.e., Torque,๐=๐นร๐โฆ(

**How do you calculate the efficiency of a shunt generator?**

The overall efficiency of a DC generator can be found by adding all the losses to the output power and comparing this with the input power.

## Which motor has maximum efficiency?

Maximum efficiency is usually near 75% of rated load. Thus, a 10-horsepower (hp) motor has an acceptable load range of 5 to 10 hp; peak efficiency is at 7.5 hp. A motor’s efficiency tends to decrease dramatically below about 50% load.

**Which DC motor has highest efficiency?**

Tests carried out on a 44 megawatt 6-pole synchronous ABB motor shortly before delivery showed an efficiency 0.25 percent greater than the 98.8 percent stipulated in the contract, resulting in the world record for electric motor efficiency.