Research — Illustrative (draft, unvalidated)
Fault current along a feeder — auto
No controls here. A 500 MVA source feeds a feeder, and the fault point travels from the bus out to 10 miles and back. All three fault currents fall as line impedance builds up. The tick marks where single line-to-ground drops below line-to-line: close to the source the line's zero-sequence path is short, further out it dominates.
Fault distance from the source
0 mi (at the bus)line-to-ground falls below line-to-line10 mi
Reading —
Feeder one-line and fault current bars (illustrative feeder, not site data)
Fault current status
Fault current (three-phase)
Loop impedance
X/R ratio
How the check read it
Client-side port:the logic and table in this page are a TypeScript port of the harness function, checked against values exported from the Python tests. Not a live API call. Module maturity, quoted from the domain page: “Draft; outputs should not feed compliance decisions until reviewed. Only conductor ampacity and the transformer hottest-spot function are anchored to an independent published reference; the grounding decrement and surface-layer factors each match one published point. Everything else is tested for internal self-consistency only.” Fault current is in the second group: internal self-consistency only, with no independent published benchmark. The port is checked against values exported from the Python function, which proves it matches the Python, not a real system. Symmetrical RMS, no DC-offset factor.Real functions this maps to:
calculate_available_fault_current, source_impedance_from_fault_mva, calculate_line_constants.Not modeled: double line-to-ground faults, fault resistance, motor contribution, transformers in the path, and asymmetry. Illustrative choices of this page, not harness defaults: source zero-sequence impedance set equal to positive-sequence, source X/R of 10, and feeder impedance from calculate_line_constants for one conductor geometry (not a particular utility's line).See also:Fault current (interactive)