Extech EX505 Multimeter Review

If you are into electrical stuff, then you must have heard of the Extech multimeter. We say that because this company is among the best makers of the instrument. If you work with HVAC appliances, you will need the best HVAC controls multimeter that walks the talk.

The Extech can test various electrical properties apart from the most obvious, like current and resistance. You will, however, be delighted to know that it’s also a good HVAC multimeter.

With that out of the way, let’s see review the Extech Ex505 multimeter and see why you should consider it.

Extech EX505 True RMS Industrial MultiMeter Review

If you are looking for an affordable multimeter that offers smooth functionality in a good design, then this is it. It is a handy companion for professionals that deal with heavy-duty HVAC appliances.

That’s because it is not only accurate but also has a simple easy to use design. The true RMS scale plays a huge role in the instrument being that accurate, which sits right for many professionals.

The scale ensures accurate results by cutting down on data distortions as much as possible. Sure, we don’t expect a multimeter to be entirely accurate, as there will always be a margin of error.

It, however, should be accurate enough with a negligible chance of getting the odd erroneous results here or there.

The Design

What immediately jumps at you is the double molded design this multimeter has. The double molding makes it waterproof and resistant to damage to the elements. It also makes it quite durable since you can’t damage it with simple falls. Related Article: Best multimeter for home and auto

The design is also quite simple, meaning you won’t struggle to get the hang of it. It, however, could give trouble to someone entirely new to the multimeter.


In addition to the regular tests, a multimeter can do this one also tests temperature. It comes with a probe that enables you to test for liquid temperature with it. Type K probe that tests for temperature is often accurate up to 400 Celsius degrees.

Autoranging and True RMS Scale

The ability of a multimeter to automatically set the range is often underestimated. That is until you have an unfamiliar multimeter in your hands. The automatic ranging multimeters are not only easier to use but also give more accurate results.

With automatic ranging, the Extech Ex 505 can set itself to a range that depends on the source of the electrical property you are testing. It also has a True RMS scale that further ensures that the multimeter’s result is as accurate as possible. Some people, however, do prefer the manual ranging multimeters, though harder to use.

Auto Shutoff

To ensure you don’t return to a dead battery, it has the auto-shutoff function. The multimeter will automatically shut off when the screen is idle for a particular time to save the battery.

Safety Rating

There is always a degree of danger when you are dealing with electrical instruments. That is why you need a safe multimeter. And this safety rating of the CAT IV 600V multimeter is quite safe. The safety rating means you can safely use it even when testing external wires prone to being dangerous.


Everyone needs a multimeter that can test different electrical properties. The Extech ticks all the right boxes as far as versatility is concerned. You can use it to test for very many electrical properties.

Some of the tests it makes possible to test as frequency, voltage, and temperature. Furthermore, it can also work in multiple environments. The fact it is water-resistant means you can use it even around water.

If you drop it in the water, you have to retrieve it and wipe it off the water. Minimal contact with water doesn’t have much effect on it.

Who Needs This Multimeter?

Extech Ex505 is the ideal multimeter for a heavy-duty HVAC professional. As such, it might not be the best option for an absolute beginner as they might have issues with a few of the features.

The fact this multimeter works best in an industrial setting means it wouldn’t be the best option for someone who’s only working with it at home. A simpler alternative would suffice at home.

However, with the manual, anyone can learn to use it. Not a lot of the futures are hard to grasp, which should give hope to a beginner.


  • Tough and durable
  • Waterproof and Accurate
  • Excellent display and Affordable


  • Testing AC voltage isn’t that fast

What We Didn’t Like

Although it has a true RMS multimeter, it can at times be entirely inconsistent with accuracy. That is a significant cause for worry since everyone would want their multimeter to be as accurate as possible.

Some of the features are also not mounted that well. For instance, the temperature infrared component could easily come off if the instrument falls. However, this doesn’t mean this isn’t a good multimeter.

What Do Users Say?

This multimeter has a rating of 3.9 out of 5. Although it has mostly good reviews there are several negative ratings regarding its durability and sturdiness.

Final Thoughts

Extech is a good option if you are looking for a sturdy and durable multimeter. It is also quite versatile. Although with a few drawbacks, you wouldn’t go wrong choosing it.

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