The noise of the motor is mainly composed of electromagnetic vibration noise, mechanical vibration noise and ventilation (aerodynamic) noise. In order to determine whether the noise generated by the motor is standardized, the motor noise will be tested specifically. Then the specific motor noise test methods are mainly divided into the following two types:

1. Establish a special test environment (silent room, silent box)

Since the motor needs a quiet environment to obtain accurate data when testing the noise, it is necessary to establish an environment that meets the requirements of acoustic testing, that is, a test silent room. The noise value in the silent room is generally lower than 40dB (A). In such a quiet environment, the noise value generated by the motor during operation can be effectively and accurately measured. If the motor is small in size, it can also be tested with a silent box. The silent box is a smaller version of the silent room. The acoustic effect and function are the same. Compared with the silent room, it is smaller in size, easy to move, and easy to carry.

2. Professional motor vibration and noise detector

There are also many manufacturers of professional noise detection instruments on the market. They will design and manufacture instruments specifically for testing motor vibration noise according to the accessories and causes of motor noise. Such instruments can also effectively measure whether the noise value of the motor meets the standard when it is working.

Regardless of which of the above test methods is used, it is worth noting that the motor should be kept in a no-load running state during the test, and the test should be carried out at the decibel level where the maximum noise is generated. The voltage and frequency should be kept at the rated value to ensure the accuracy of the test data as much as possible.