Prospective fault current
Updated 2026-10-27
Data records
- Prospective fault current is the current that would flow if a fault of negligible impedance occurred at a given point in an installation; the ground fault value follows from the supply voltage and the loop impedance between the line and protective conductors, and the short-circuit value from the line-to-neutral impedance.
- An installation tester derives the prospective ground fault current by dividing the measured supply voltage by the measured line-to-protective-conductor loop resistance, and the prospective short-circuit current by dividing it by the measured line-to-neutral resistance, showing the current beside the impedance reading.
Elsewhere in the family
- Energization Checks related entry on Electrical Testing Reference
Sources
- Electrical Testing Reference editorial taxonomy, Electrical Testing Reference editorial taxonomy of test methods, 2026-10 edition, Electrical Testing Reference. Held as: Own observation.
- Fluke product page, Fluke 1664 FC Installation Multifunction Tester, web page edition, Fluke. Held as: Public page. Publisher page
Changelog (4 entries)
| Date | Revision | Change |
|---|---|---|
| 2026-10-27 | created (gloss.prospective-fault-current.definition) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (gloss.prospective-fault-current.definition) | |
| 2026-10-27 | created (gloss.prospective-fault-current.usage) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (gloss.prospective-fault-current.usage) |
Cite this page
Cite the governing standard for the fact itself; cite this page as the finding aid.
"Prospective fault current." Test Instrument Reference. 2026-10-27. https://www.testinstrumentreference.com/glossary/prospective-fault-current/.
Test Instrument Reference, Prospective fault current (Oct. 27, 2026), https://www.testinstrumentreference.com/glossary/prospective-fault-current/.
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title = {Prospective fault current},
howpublished = {\url{https://www.testinstrumentreference.com/glossary/prospective-fault-current/}},
organization = {Test Instrument Reference},
publisher = {Test Instrument Reference},
year = {2026},
note = {last substantive change 2026-10-27}
}{{cite web |title=Prospective fault current |website=Test Instrument Reference |publisher=Test Instrument Reference |url=https://www.testinstrumentreference.com/glossary/prospective-fault-current/ |date=2026-10-27 |access-date=}}