What does the action of grounding vehicles together during electrical work help to prevent?

Grounding vehicles together during electrical work is primarily focused on preventing step potential damage. When performing electrical tasks, especially in environments where high voltages are present, there exists a risk that a fault could cause a substantial voltage difference between the ground and the vehicles. If these vehicles are not grounded together, this voltage difference can create a potential for current to flow between them, resulting in a dangerous step potential situation where a person could become the path to ground if they are standing between the vehicles or touching both.

By grounding the vehicles, any potential electrical charge that may build up is safely dissipated to the earth, ensuring that a uniform voltage level is maintained between the vehicles. This effectively minimizes the risk of harmful voltage differences that could lead to electric shock or other electrical hazards. As such, grounding is a crucial safety measure in maintaining a safe working environment when multiple vehicles are involved in electrical operations.