Klein Tools RT250 GFCI Outlet Tester

The Klein Tools RT250 GFCI Outlet Tester puts a refreshing new spin on the traditional GFCI outlet tester. Coming in at only around $21 USD, this thing is a steal of deal.

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Link to purchase from Lowes: Klein Tools RT250 GFCI Outlet Tester

5 things that make this stand out:

1) The first and probably most obvious thing worth mentioning is the beautifully lit LCD display. While most receptacle testers use a chart and light combination to decipher whether your receptacle has been wired correctly or not, this clearly tells you the results directly on the backlit display. It can be easily read in a dark room or even in direct sunlight.

2) The second thing that makes this stand out is that it gives you the voltage reading. Most GFCI outlet testers, and even some in the same price range, don’t have this feature. This can be a very valuable piece of information to have while you’re troubleshooting.

3) A third and highly underrated feature on the RT250 is how bright and vibrant the “correct” and “fault” LED indicator lights are. Some testers can be very difficult to read and decipher whether or not the receptacle has been wired correctly or not because their lights are dim and finicky. That’s not an issue with the RT250, as there’s no mistaking whether your receptacle is faulty or functional when you see these indicator lights illuminate. You can easily see them from across the room, which can save you some time if you’re running a one man show.

4) A fourth killer feature of the RT250 is the fact that the GFCI tester actually tells you how long it took the GFCI to trip. It’s a fantastic feature that’s not seen in many GFCI testers. This can be a very valuable piece of information while troubleshooting. If your GFCI isn’t tripping immediately, you’ll know that it’s probably time to replace it.

5) The fifth, and arguably best feature of the RT250, is a feature that Klein Tools calls the “auto hold function”. In the humble opinion of Mad Electrician, this is a complete game changer. Since the RT250 is powered using three AAA batteries (which are included with the tester) when it’s unplugged from testing, it will actually hold the results on the LCD display for 10 seconds. This means that if you’re testing a receptacle that’s in a hard to reach place, or anywhere that prevents you from being able to read the LCD display, you’ll have 10 seconds after unplugging it to read the results. With most other testers, in these situations, you’re pretty much just out of luck.

The negative:

There’s really only one complaint that Mad Electrician has with the Klein Tools RT250, and that’s the fact that without the three AAA batteries, it won’t work. At all. Now this isn’t a huge deal, especially since most meters and testing equipment require batteries to function anyways. It’s understandable that the tester doesn’t hold any readings while it’s unplugged since it doesn’t have a power source, but it would be nice if it still functioned like simpler testers while plugged in, even if that just meant illuminating the “correct” and “fault” lights. Thankfully, the RT250 does seem to have a good battery life, and it doesn’t turn on by accident very easily, so you shouldn’t find yourself in many situations where this is an issue.

Final thoughts:

All in all this is a fantastic tester. For only around $21 (depending on where you purchase from), this thing is an absolute steal of a deal. If you don’t own one yet and you’re an electrician, or even just someone who does the occasional electrical project, this is a no brainer.

Watch the Full Review:

See Mad Electrician’s video “This is Way Cooler Than I Thought - Klein Tools RT250 GFCI Outlet Tester” for an in depth, no non-sense review.