Guide: Proper cooling is therefore important

When an electric motor is in operation, the rotor and stator loss generate heat, which must be controlled using an appropriate cooling method.

Efficient cooling - or lack of it - has a significant impact on the life of the motor. This is especially true of the bearings and the insulation system, which are the components most vulnerable to overheating. Prolonged overheating can also cause metal fatigue.

The following rule of thumb illustrates the relationship between heat and lifetime:

• The service life of the motor's insulation system is divided by two for every 10 °C above the rated temperature and multiplied by two for every 10 °C below the rated temperature.
• The service life of the motor's bearing grease is divided by two for every 15 °C above the rated temperature and multiplied by two for every 15 °C below the rated temperature.

In addition to ensuring the life of the motor, it is important to maintain optimal temperature levels to avoid overall efficiency reduction.

Correct thermal control thus provides a more reliable and robust motor with a longer life. And with an efficient cooling system, it is often possible to use a smaller motor, which also leads to significant reductions in size, weight and cost.

There are many cooling options for electric motors. The optimal choice depends on your application, the operating environment in which the motor is installed and several other factors.