Only in a perfect world would there be zero current on a ground wire.
The current can be measured by measuring the field around the wire. There are many manufacturers of clip on ammeters which make a loop around the wire and then measure
The current or potential induced in the loop by the field resulting from the current in the ground wire.
That video was truly horrible. Was that metal scaffolding? I am surprised that fault carried on for 3
Minutes. A fuse should have blown or other protection operated.
Maybe if it was wooden scaffolding it was a high impedance fault undiscernable from high loads.
A clip on ammeter is is a good recommendation. I don't know how sensitive they were and the nature of the stray voltage.
The video was indeed terrible. I'm guessing the scaffolding was metal but that the wheels were rubber (it seemed as though the current was only going though the workers).
The current can be measured by measuring the field around the wire. There are many manufacturers of clip on ammeters which make a loop around the wire and then measure The current or potential induced in the loop by the field resulting from the current in the ground wire.
That video was truly horrible. Was that metal scaffolding? I am surprised that fault carried on for 3 Minutes. A fuse should have blown or other protection operated.
Maybe if it was wooden scaffolding it was a high impedance fault undiscernable from high loads.