[Al_The_Man]

Installed many systems earth grounding the DC supplies common and have not had a problem, I set up a 1/4" tapped copper ground plate and take every earthed common to it.
Together with equi-potential bonding.

Per the PDF: The concept of Earth consists of one homogeneous mass that is electrically neutral, i.e.
an equal number of negative and positive charges are distributed throughout the earth at any given time.

[mactec54]

Together with equi-potential bonding.

And how many Hobby user's can achieve this here on the Zone, you are talking a foreign language to a Hobby user, which only ends up with more problems, when they try and achieve a system that has an equi-patential bonded Ground system, what you did in the industry does not equal Hobby user, this is for dreamers only, you have been here long enough to know that

[Algirdas]

There is nothing complicated actually. Only the problem is the way of explanation. It depends on the level of understanding and education background. Up to now the best description of "grounding" and protective earth belongs to Siemens in my opinion. I recommend to learn. Covers almost all aspects of earthing, Very detailed.
Contains no expressions like "returning to source" or so.

[mactec54]

There is nothing complicated actually. Only the problem is the way of explanation. It depends on the level of understanding and education background. Up to now the best description of "grounding" and protective earth belongs to Siemens in my opinion. I recommend to learn. Covers almost all aspects of earthing, Very detailed.
Contains no expressions like "returning to source" or so.

If you are talking about Ac Power Earth Ground circuits then that would be correct, you are not going to find source being used in an Ac circuit, understand what is being discussed would help you understand why the word source is used

[Al_The_Man]

There is nothing complicated actually. Only the problem is the way of explanation. It depends on the level of understanding and education background. Up to now the best description of "grounding" and protective earth belongs to Siemens in my opinion. I recommend to learn. Covers almost all aspects of earthing, Very detailed.
Contains no expressions like "returning to source" or so.

Agree!
Good comment!