Three lamps find wiring faults; they do not find a bad earth
A socket tester is three lamps and a legend: a pattern of lit and unlit indicators maps to reversed live and neutral, a missing earth, or a missing neutral. It is the fastest way to find a crossed pair in a room full of sockets. What it cannot do is judge the quality of an earth — a high-resistance connection can still light the lamp — and better models say so on the case. Some add an RCD trip test. We compare the faults indicated, RCD testing, socket standards covered, display type, and the documented limits.
Six fault types · RCD test · LCD voltage display · leakage measurement
A socket tester with an LCD showing the actual voltage, six wiring fault indications, an RCD trip test and a leakage measurement — the fullest function list in this hub, at the lowest price.
Best for: Checking a whole property quickly, where reading the actual voltage saves a second trip with a multimeter.
Battery-free · Schuko sockets · trips a 30 mA RCD from a test button
A battery-free socket tester for Schuko outlets that trips a 30 mA RCD directly from its test button — nothing to go flat, nothing to forget.
Best for: The tester that lives in the bag for a year and works when you finally reach for it.
2.0-inch LCD · RCD test at 30 mA / 230 V AC · connection and wiring faults
A trade socket tester with a 2.0-inch LCD reporting the connection state, and an integrated RCD test at 30 mA on 230 V AC.
Best for: Checking many sockets in sequence, where a readable screen beats decoding a lamp pattern each time.
CAT II 300 V stated · six fault types · six LEDs · one-button RCD test
A socket tester stating CAT II 300 V — the only socket tester here that publishes a category — with six LED indications and a one-button RCD trip test.
Best for: The socket tester to buy if you want to know where the instrument is rated to be used.
Socket tester with RCD trip · plus a 12–1000 V contactless pen · auto power-off
A two-piece kit: a socket tester with RCD trip function and a separate non-contact voltage pen covering 12 to 1000 V, with automatic power-off after three minutes.
Best for: Equipping someone from nothing, where owning both tools matters more than owning the better one of each.
Reversed conductors, a missing earth and a missing neutral or line. The most common faults.
An earth that is present but poorly connected, an insulation fault, an insufficient conductor size. It does not replace a full check.
A residual current device should be tested periodically to confirm it still trips. The tester's button does that, by cutting the circuit.
A general reversal often comes from the board rather than the sockets. Useful information in itself.
It is designed for one socket type and one earthing system. Old or foreign sockets can give unusable readings.
No, the opposite: it works on a live socket. A check on a live installation.
Do not intervene without competence: reversed wiring or a missing earth are for an electrician. The tester establishes; it does not repair.
It spots reversed wires, a missing earth or a broken neutral, not a poor earth or an undersized conductor. A full check needs a measuring instrument and a qualified person.
A socket tester sees reversals and a missing earth, not a poorly connected earth or an insulation fault: it does not replace a full check. A reversal on every socket points at the board, and a fault found is a matter for an electrician.
A column is raised only if four instruments in five publish the value. Below that, it would be measuring the silence of the manuals.
| Model | Price | Faults detected | Functions |
|---|---|---|---|
| amropi 745302626168 | — | — | Socket tester with RCD trip · auto power-off |
| PANCONTROL PAN SOCKET-TEST-2 | — | Schuko sockets | trips a 30 mA RCD from a test button |
| Testboy Testavit Schuki 6 | — | connection and wiring faults | — |
| GOMETY PBY39 | — | six fault types | one-button RCD test |
| Wigearss INSP0533 | — | Six fault types | RCD test · leakage measurement |
Specifications: manufacturer sheets for measuring instruments and the matching Amazon product pages. Prices and availability: Keepa. Every figure in this table names its source.
Most recent revision in this category: August 31, 2026.
