What is the grounding resistance of the motor?

In the case of a motor, the absolute resistance of the coil to the casing should be 5m or higher, the absolute resistance between the coil groups of each phase should be 2m or higher, and the grounding resistance of the motor protection grounding should be 4-8 ohms.

Grounding resistance is an important parameter to measure the grounding state. It is the resistance encountered by the current flowing from the grounding device to the earth, then to another grounding body or to a far place. It includes the resistance between grounding wire and grounding body, the contact resistance between grounding body and earth, the resistance between two grounding bodies or the resistance from grounding body to infinite grounding.

Grounding resistance directly reflects the good degree of contact between electrical equipment and "ground" and also reflects the scale of grounding grid. The concept of grounding resistance is only applicable to small grounding grids; With the increase of grounding grid area and the decrease of soil resistivity, the inductive component in grounding impedance plays an increasingly important role, so large grounding grids should be designed with grounding impedance.