Tech & Gadgets · Head-to-head
Klein Tools RT250 GFCI Receptacle Tester with LCD vs IDEAL Electrical 61-502 120V AC GFCI Receptacle Tester
Which should you buy? Our verdict on both, pulled from our full The Best Outlet Testers: 4 Compared (and One to Skip) comparison.
The RT250 is the only tester in this group that reports the supply voltage and the GFCI trip time as numbers instead of a lamp pattern, and Klein publishes the list of conditions it does not indicate. The IDEAL 61-502 gives you the same certified wiring indication with a GFCI button and nothing else, which is the right trade for a second bag or a drawer.
Klein Tools RT250 GFCI Receptacle Tester with LCD
Buy itThe tester that shows you an actual voltage and an actual GFCI trip time instead of asking you to decode three lamps.
- The backlit LCD names the fault and displays line voltage, so a supply that is low or high shows up as a number you can act on.
- Reports the time a GFCI took to trip after the tester creates its 6 mA to 9 mA ground fault.
- Klein publishes a full instruction sheet that states outright which conditions the tester does not indicate, quality of ground among them.
- Conforms to UL 1436, so it cannot assess the grounding circuit however green the display reads.
- Klein's own note says it does not indicate reversal of neutral and ground conductors, multiple hot wires, or combinations of defects beyond a dual open neutral and ground.
- CAT II 135 V keeps it at the receptacle, not at the distribution side of the installation.
IDEAL Electrical 61-502 120V AC GFCI Receptacle Tester
Buy itA plain lamp tester with a GFCI button, certified to the same wiring standard as the screens, and honest on its own product page about needing a real ground.
- Indicates correct wiring plus open ground, reverse polarity, open hot, open neutral, hot and ground reversed, and hot on neutral with hot open.
- cULus certified to UL 1436 and CSA C22.2 No. 160, the same indication standard the LCD models are built to.
- IDEAL states on the product page that the receptacle must be properly grounded for the GFCI test to work, which is the failure people usually blame on the tester.
- No display, so you get a lamp pattern and no voltage reading at all.
- No GFCI trip time, so you learn that a device tripped but not how quickly it did.
- Same UL 1436 blind spots as every lamp tester, ground quality included.
Side by side
| Klein Tools RT250 GFCI Receptacle Tester with LCD | IDEAL Electrical 61-502 120V AC GFCI Receptacle Tester | |
|---|---|---|
| Our verdict | Buy | Buy |
| Best for | Anyone who wants one plug-in tester and would rather read a voltage and a trip time than a pattern of lamps. | A second bag, a service van door pocket or a kitchen drawer, where a certified basic wiring check is all you actually need. |
| Price tier | $$ · mid-range | $ · budget |
The bottom line
Our overall pick is the Klein Tools RT250 GFCI Receptacle Tester with LCD - The tester that shows you an actual voltage and an actual GFCI trip time instead of asking you to decode three lamps. Choose the IDEAL Electrical 61-502 120V AC GFCI Receptacle Tester instead if a second bag, a service van door pocket or a kitchen drawer, where a certified basic wiring check is all you actually need.
Want the full picture, including the other options we compared and the popular one we'd skip? Read the complete The Best Outlet Testers: 4 Compared (and One to Skip).