Best Non-Contact Voltage Testers: Buying Guide

Updated Feb 27, 2021

If you feel confident in handling basic home electrical projects, such as replacing a wall switch, receptacle, light fixture, doorbell, or thermostat, you’ll need essential electrical tools, which include a way to check for the presence of AC electricity. This is where the non-contact voltage testers come into play.

Recall note: Klein recalled about 1.69 million NCVT-1 testers in 2021 because they could look ready when they wouldn’t detect voltage. The recall covers date codes ending in H7. If you own one, check it against CPSC’s notice. For current picks, see our voltage tester guide.

Top Pick: Klein NCVT-4 w/ IR Thermometer

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What to like:

A voltage tester may not need to survive the demands of a rugged environment, but I still appreciate the use of thick plastic and heavy-duty construction.
Having a screw cap for battery replacement may seem like a small detail, but compared to other brands and models that require squeezing and / or prying the battery cover off, the screw cap is a great feature.
You’ll notice the absence of the flat extended tip, so you test from the surface of the receptacle. A silent tester doesn’t prove that a receptacle is dead, especially a tamper-resistant one, so confirm with a second tester before you touch any wires.
The dual-range capabilities (12-1000VAC) can detect voltage on AC electric throughout the home: outlets, cords, switches, circuit breaker, power strip, thermostats, doorbells (before and after the transformer), humidistat, and security systems.
There isn’t a flashlight on the NCVT-4, as the IR thermometer takes up that space, but the Blue LED standby lamp is bright enough to help light dim areas.
The IR thermometer is very useful for investigating air leaks and lack of adequate insulation. Is the built-in IR thermometer a proper substitute for a thermal imaging camera? No! But you can conduct surface temperature variation tests to make a few home efficiency improvements.

In Summary: I have always preferred Fluke electrical tools, and I wasn’t initially convinced that I needed to keep a non-contact voltage detector, as my Fluke T+PRO Electrical Tester already has a lot of great features: detect live voltage even when the batteries are dead, detect AC/DC voltage, GFCI trip, and the backlit LED display gives exact voltage numbers.

As useful as the Fluke T+PRO is, the Klein NCVT-4 also has its key attributes, and I’m happy to keep both devices in my electrical tool kit.

Best Non-Contact Voltage Tester with LED Light: Milwaukee 2202-20

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Best Non-Contact Voltage Tester for Standard and Low Voltage: Klein Tools NCVT-2

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Best Non-Contact Voltage Tester with Flashlight: Extech DV25

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Non-Contact Voltage Detector Buyer’s Guide

Easy to Use: Place the tip of a non-contact voltage tester near a device or wire where AC voltage is present. The tip will illuminate or change colors from its standby mode – and an audible alert may sound (varies per detector) – if voltage is detected.

Technical Details: To better understand how a non-contact voltage detector works, we’ll defer to the professionals at Fluke.

Understanding the Comparison Chart: Some of the information is self-explanatory, but the listed information may not be.

Maximum Voltage Range: A typical single household circuit from the electrical panel ranges from 110-240 VAC. The difference between a 600 or 1000 VAC capable detector will be irrelevant for common homeowner use and only pertains to trained professionals working with higher voltage applications, e.g. outside power coming to the circuit panel.
Low Voltage Range: To check thermostats and doorbells (transformer outlet), a low voltage or dual-range detector will be needed, as these components typically operate at 24VAC or lower.
CAT III Rating: Refers to measurements on hard-wired equipment in fixed installations, distribution boards, and circuit breakers. Other examples are wiring, including: cables, bus bars, junction boxes, switches, and socket outlets in the fixed installation.
CAT IV Rating: Rated test instruments are designed for testing on the primary supply source, which also includes 120V or 240V overhead or underground lines that power detached buildings or underground lines that power well pumps. The CAT IV rating covers the highest and most dangerous level of transient over-voltage.

DID YOU KNOW? Depending on the context, low-voltage and high-voltage are relative terms and vary by definition. Understand the type of electricity – mains electricity – delivered to your home.

MANUFACTURER & MODEL	VOLTAGE RANGE	CAT RATING	AUDIBLE INDICATOR	WORK LIGHT	POWER SWITCH	BATTERY TYPE
EXTECH DV40 + IR THERMOMETER	50 – 1000VAC	CAT III – 1000V			✓	3 x LR44
EXTECH 40130	100 – 600VAC	CAT III – 600V	✓		✓	2 x AAA
EXTECH DV20	100 – 600VAC	CAT III – 600V		✓	✓	2 x AAA
EXTECH DV24	50 – 1000VAC	CAT IV – 1000V		✓	✓	2 x AAA
EXTECH DV25 DUAL-RANGE	24 – 1000VAC	CAT IV – 1000V	✓	✓	✓	2 x AAA
EXTECH DV26	100 – 1000VAC	CAT III – 1000VAC, CAT IV – 600VAC	✓	✓	✓	2 x AAA
EXTECH DV30 ADJUSTABLE SENSITIVITY	12 – 600VAC	CAT III – 600V	✓			4 x LR44
EXTECH DVA30 + CURRENT	12 – 600VAC, 200mA to 1000A	CAT III – 600V	✓			4 x LR44
FLIR VP50	24 – 1000VAC	CAT IV – 1000V		✓	✓	2 x AAA
FLUKE 2AC VOLTALERT™	90 – 1000VAC	CAT IV – 1000V				2 x AAA
FLUKE 1AC-II A1 VOLTALERT™	90 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
FLUKE 1AC II A2 VOLTALERT™	90 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
FLUKE 1LAC II A VOLTALERTT™	20 – 90VAC	CAT IV – 1000V	✓		✓	2 x AAA
FLUKE LVD2 VOLT LIGHT	90 – 600VAC	CAT IV – 600V		✓	✓	1 x AAA
GREENLEE GT-12A	50 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
GREENLEE TR-12A	50 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
GREENLEE GT-16 ADJUSTABLE	5 – 1000VAC	CAT IV – 1000V	✓			1 x AAA
KLEIN NCVT-1	50 – 1000VAC	CAT IV – 1000V	✓	✓	✓	2 x AAA
KLEIN NCVT-2	12 – 1000VAC	CAT IV – 1000V	✓	✓	✓	2 x AAA
KLEIN NCVT-3 W/ LED BAR GRAPH	12 – 1000VAC	CAT IV – 1000V	✓	✓	✓	2 x AAA
KLEIN NCVT-4 W/ IR THERMOMETER	12 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
MILWAUKEE 2202-20	50 – 1000VAC	CAT IV – 1000V	✓	✓	✓	2 x AAA
MILWAUKEE 2200-20	50 – 1000VAC	CAT IV – 1000V	✓		✓	2 x AAA
MILWAUKEE 2203-20 DUAL-RANGE	10 – 49VAC, 50 – 1000VAC	CAT IV – 1000V	✓	✓		2 x AAA
SANTRONICS ULTIMATE AC	50 – 1000VAC	CAT IV – 1000V	✓			2 x AAA
SANTRONICS AC	50 – 1000VAC	CAT IV – 1000V				2 x AAA
SANTRONICS LOW AC	24 – 90VAC	CAT IV – 1000V				2 x AAA
SANTRONICS DC	6 – 50VDC	N/A	✓
SPERRY VD6504	50 – 1000VAC	CAT III – 1000V, CAT IV – 600V	✓		✓	1 x AAA
SPERRY VD6505 – ADJUSTABLE	12 – 1000VAC	CAT III – 1000V, CAT IV – 600V	✓		✓	1 x AAA

Empirical Data: Beyond explaining and comparing the common specs between voltage detectors, we also selected and purchased several of the non-contact voltage detectors to include firsthand observations, and we chose a top pick.

Each brand and model tested had different audible sound levels. I would like to see manufacturers list the db level in their specs as it can be an important factor.
All testers detected static electricity. However, the manufacturers took this false reading into consideration. Non-contact voltage detectors will only cause flashes of light and possibly single chirps – instead of a steady light and steady audible alarms for true voltage.
A response from Santronic said, “Our voltage testers are manufactured, printed, and packaged in the US.”