Why is this important?
Regardless of whether the reference is to a main or a control circuit: Provided that no risk is present, an initial insulation fault should not trip a protective device and thus lead to an immediate interruption of the circuit. Particularly in complex, interrelated processes, a shutdown can have fatal consequences, shut down the entire production and also damage machinery.
In some cases not only the machinery has to be repaired, but high restart costs can also be incurred. This is where the machinery planner or designer comes in. By selecting the right system type, potential hazards can be prevented and, as a result, maintenance can be rendered more predictable and cost-effective.