Section 111.51-5 - Protection of vital equipment(a) The coordination of overcurrent protective devices must be demonstrated for all potential plant configurations.(b) Protective relays and overcurrent protective devices must be installed so that: (1) A short-circuit on a circuit that is not vital to the propulsion, control, or safety of the vessel does not trip equipment that is vital; and(2) A short-circuit on a circuit that is vital to the propulsion, control, or safety of the vessel is cleared only by the protective device that is closest to the point of the short-circuit.