Leakage clamp meter
Updated 2026-10-27
Data records
- A selectable low-pass filter restricts the reading to the power-frequency fundamental, excluding harmonic currents from the measurement.
- Recording and comparing leakage readings over time on a live circuit shows a rising trend before it causes a failure or a nuisance trip, so a developing problem is found without taking the equipment out of service.
- Instruments of this class log readings internally or to a mobile application and include a comparator that flags a reading above a set threshold, which speeds up locating a leakage source among many circuits.
- A leakage clamp meter measures small alternating currents, typically the leakage current in a ground conductor, with a clamp jaw whose construction and shielding keep external fields from distorting readings at the lowest levels.
- Leakage clamp meters are used to locate the source of intermittent GFCI and RCD trips by reading the standing leakage of each circuit and appliance while it runs, without disconnecting anything.
- The resolution of the lowest range is what distinguishes a leakage clamp from a general clamp meter: the finest step is a small fraction of a milliampere, while the upper ranges of the same instrument cover ordinary load currents.
- Measurement is true RMS, so leakage with a complex, non-sinusoidal waveform is read correctly.
Sources
- AEMC product page, Clamp-on Leakage Current Meter Model 566, web page edition, AEMC Instruments. Held as: Public page. Publisher page
- Fluke product page, Fluke 368 FC Leakage Current Clamp Meter, web page edition, Fluke. Held as: Public page. Publisher page
- Hioki product page, AC Leakage Clamp Meter CM4001, web page edition, Hioki. Held as: Public page. Publisher page
Changelog (15 entries)
| Date | Revision | Change |
|---|---|---|
| 2026-10-27 | created (instr.leakage-clamp-meter.filter) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.filter) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.insulation-live) | |
| 2026-10-27 | revised (instr.leakage-clamp-meter.insulation-live) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.insulation-live) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.logging-comparator) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.logging-comparator) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.principle) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.principle) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.rcd-trips) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.rcd-trips) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.resolution) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.resolution) | |
| 2026-10-27 | created (instr.leakage-clamp-meter.true-rms) | |
| 2026-10-27 | review_status unreviewed -> software_reviewed (instr.leakage-clamp-meter.true-rms) |
Cite this page
Cite the governing standard for the fact itself; cite this page as the finding aid.
"Leakage clamp meter." Test Instrument Reference. 2026-10-27. https://www.testinstrumentreference.com/instruments/leakage-clamp-meter/.
Test Instrument Reference, Leakage clamp meter (Oct. 27, 2026), https://www.testinstrumentreference.com/instruments/leakage-clamp-meter/.
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title = {Leakage clamp meter},
howpublished = {\url{https://www.testinstrumentreference.com/instruments/leakage-clamp-meter/}},
organization = {Test Instrument Reference},
publisher = {Test Instrument Reference},
year = {2026},
note = {last substantive change 2026-10-27}
}{{cite web |title=Leakage clamp meter |website=Test Instrument Reference |publisher=Test Instrument Reference |url=https://www.testinstrumentreference.com/instruments/leakage-clamp-meter/ |date=2026-10-27 |access-date=}}