This is a rough shot... Voltage violations would relate to the allowable delivered voltage range and deviation extent/time. So, power distributors should deliv

This is a rough shot... Voltage violations would relate to the allowable delivered voltage range and deviation extent/time. So, power distributors should deliver, through a transformer say 235V±10V and allowable deviation might be some number of cycles (2? No idea) The real collapse arises when the power demand reaches the limits of the distribution leg. Maybe the local substation is rated at 1 GW. As the number of loads grows in a step-wise manner the components of the system reach capacity and voltage reduction occurs as amperage and power output is increased