If service equipment is modified, is it necessary to recalculate the available fault-current?

Modifying service equipment can have various implications on the system's overall fault-current levels. When service equipment is altered, whether through the addition, removal, or replacement of components, it can change the impedance of the circuit. These changes might increase or decrease the available fault current at any point within the system.

Recalculating the available fault current is essential because it ensures that protective devices, such as circuit breakers and fuses, are adequately rated to handle potential faults without failing. This evaluation helps to maintain system safety and compliance with electrical codes, which are aimed at preventing equipment damage or safety hazards in the event of a fault condition.

Therefore, it's vital to assess the fault-current levels each time the service equipment is modified, as this practice aligns with safety standards and best practices in electrical engineering.