Grounding is a very critical safety protection requirement for motor products, no matter for motor or for operators and supporting equipment; Hengli motor GB14711 and GB755 are two key standards for motor products. For grounding related requirements, specific content is given in the standard. However, many motor manufacturers will deal with the motor grounding link poorly because of cognition or other factors. Hengli motor has strict control procedures from supplier selection and production process.

According to the requirements of the production standard, the motor must have a protective grounding device in accordance with the provisions, and the electrical connection between the motor stand and the protective grounding device should be permanent, reliable and good. When the motor moves on the equipment base, the protective grounding conductor should still be able to be reliably connected.

In the actual production and transportation, for most of the motor products, only the grounding mark and grounding screw are left on the motor body, and the grounding wire is provided by the customer; For long lead motors, most grounding wires are provided by the motor manufacturer. However, in view of the cognition problem between the supply and demand sides of grounding wire, there are always some random grounding parts of the motor, no matter the color or diameter of grounding wire, many of them do not meet the requirements. In order to prevent the occurrence of safety problems, whether the motor manufacturer or user, should be strictly in accordance with the provisions.

Basic requirements for motor grounding protection

● The motor must have a protective earthing device in accordance with the regulations. There should be a permanent, reliable and good electrical connection between the motor stand and the protective earthing device. When the motor moves on the equipment base, the protective earthing conductor should still be able to be reliably connected.

● If the motor USES wiring terminal to connect the ground wire, the wiring terminal shall meet the specific requirements. The connection of the protective grounding terminal shall be reliably locked to prevent accidental rotation and prevent the reduction of electrical clearance and creepage distance. It shall not be loosened without tools.

● The protection grounding terminal should not be used for any other purpose than protection grounding.

● The materials used to protect the ground conductor and the ground terminals and their connecting devices shall be compatible, resistant to electrical corrosion and good electrical conductors. If ferrous metal is used, electroplating or other effective measures should be taken to prevent corrosion.

● The grounding conductor shall be tough enough to withstand the vibration stress of the motor, and appropriate protection measures shall be taken to prevent the risk arising during the use and installation of the motor.

● The protective grounding connection shall be able to ensure true penetration of non-conductive coating layers such as paint. The connection may be cold pressed or by other equivalent means, and no hinged or soldering alone shall be used.

● The grounding body that penetrates the elastic rubber base shall be metal and shall not be grounded with conductive rubber.

Low grounding resistance of the path should be no greater than 0.1 Ω.