Electrical standards

[Jako13!]

Does anyone know of any electrical standards that require the earth ring of the supply cable to be connected to the motor chassis I see a lot of new installs like it?

 

[telectrix]

maybe to eliminate the possibility of poor electrical conductivity between terminal housing and motor body.

 

[cliffed]

No,maybe high spec demanding it.

 

[Megawatt]

View attachment 62547
Does anyone know of any electrical standards that require the earth ring of the supply cable to be connected to the motor chassis I see a lot of new installs like it?

It looks like a redundant ground maybe in a hazardous location