If you have a robust insulation resistance testing program for your major cabling, it's unlikely a cable failure will happen. Unfortunately, most facilities do not have such a program. Plus, unlikely does not mean impossible, even if you do have such a program. In fact, these failures always seem to happen during a major heat wave, in the dead of winter, or in the middle of a critical production run.
Speed and safety are both essential when a cable failure occurs. Many people see these two goals as being diametrically opposed, as if you improve one at the cost of the other. But with proper planning, these goals work in the same direction.
Trying to plan when you're already in emergency mode doesn't work too well, and that kind of high-pressure situation is when people are most tempted to cut safety corners to save time. So plan now. Material acquisition is the first step.
Odds are you don't have spools of 400MCM cable sitting around. But somebody does, because cables do fail and that size of cable is nearly always in a critical application. What can you do to ensure you can quickly find who has the cables you need, when you need them? We'll answer this question in Part 2.