# What does the rated power of motor really mean?

In everyone’s opinion, the treadmill may be a very familiar product, but you may not be familiar with the knowledge of some components related to the treadmill. Do you know the power of the treadmill motor in general? How does treadmill motor work? It is estimated that you do not know, this is some professional knowledge, and then I will introduce the rated power of motor for the treadmill. ## What is the rated power of the motor?

Electric treadmills are usually driven by the operation of the motor (motor), so the power of the motor generally refers to the rated power of motor, that is, the maximum power that can operate normally for a long time under the rated voltage (note that it is long-term operation, not short-term operation). , also refers to the mechanical power of the output end of the treadmill motor when it runs under the rated conditions specified by the manufacturer, and the unit is generally kilowatts (kW). If it is idling, its power is much smaller than the rated power; if it is overloaded, the power will exceed its rated power in a short time, but it cannot run for a long time, otherwise it will burn out.

This is the definition of the rated power of the motor on Wikipedia

## How to calculate rated power of motor?

The rated power of motor is its output power, and in the case of an electric motor, its shaft power. The input electrical power of the motor is larger than its rated power. Use the root number 3 to multiply the rated voltage and rated current of the motor, and then multiply the power factor. The value is larger than the rated power, which is the electrical power of the motor. Only by multiplying the efficiency, its value is equal to the rated power.

The motor power calculation formula can refer to the following formula:
P= F×v÷60÷η
In the formula, P power (kW), F traction force (kN), v speed (m/min), η transmission machinery efficiency, generally about 0.8.
For example, if η=0.8, μ=0.1, k=1.25 in this example,
P= F×v÷60÷η×k = 0.1×0.6KN(60KG)÷0.28÷0.8×1.25=0.33kW

## The difference between rated power and actual power of motor

Rated power refers to the power of the electrical appliance when it is working normally. Its value is the rated voltage of the appliance multiplied by the rated current. If the actual power of the electrical appliance is greater than the rated power, the electrical appliance may be damaged.

Under normal operating conditions, the output power of power equipment or the input power of equipment that consumes energy. Often in “kilowatts” as a unit. It also refers to the power that a factory-produced machine can achieve when it is working normally. That is to say, the power of a machine is usually referred to. The rated power of the machine is certain, P=Fv, so the force generated by the machine is inversely proportional to the running speed. For example, when the car is driving on a flat asphalt road, the traction force F required is small, and the speed per hour can be larger; when the road is uneven or uphill, the traction force required is large, and it must be driven at a low speed.

The actual power is to describe the energy consumed per unit time in the actual power consumption process of the electrical equipment. For the same electrical appliance, the voltage engraved on the nameplate is the rated voltage of the electrical appliance. When the electrical appliance works under this voltage, the power obtained is the rated power. In this case, the actual power is numerically equal to the value of the rated power. However, in most cases, the electrical appliance will not work under this voltage, so when the voltage across the electrical appliance is greater or less than the rated voltage, the power of the electrical appliance will increase or decrease with the change of the voltage. The power is called the real power.

## The relationship between rated power and actual power

The rated power of motor refers to the power marked on the nameplate of the motor, which indicates the maximum power that the motor is allowed to carry in a safe state. The actual power refers to the power dragged by the motor when it is actually running. The size is determined by the load and is equal to the product of the actual current and the actual voltage (the AC motor also includes the power factor); the actual power is less than the rated power, and the motor is safe to run. of. Their relationship is:

Rated power = rated current IN * rated voltage UN * root 3 * power factor

Actual power = actual current IN * actual voltage UN * root 3 * power factor

Since the calculation is too professional, we can have a general understanding. As long as we know that the motor with higher rated power, the cost will naturally be higher.