No toolbox is complete without a non-contact voltage tester. It gives you a quick, easy and reliable way to check whether a wire or outlet is carrying electric current. Since the first step in working on electric equipment is to make sure that it is not energized, you can see why a NCVT is an essential tool for hobbyists and professionals alike.
No matter if you want to replace a light fixture, doorbell, outlet or need to work on electrical wiring, a non-contact voltage tester is the tool that lets you know whether it is safe to proceed. It is a useful tool for any project that involves alternating current (AC).
There are many different non-contact voltage testers available, and it can be tricky to figure out which one to buy. To make it easier for you, I have compiled a list of the best non-contact voltage testers and added a buyer’s guide that tells you what to keep an eye on when purchasing one.
| Best NCVT | Summary | Price | Best Offer |
|---|---|---|---|
| Klein Tools NCVT-3 | Best overall | $32 | |
| Fluke 1AC II VoltAlert | Best high-end | $35 | |
| Klein Tools NCVT-2 | Best on a budget | $25 | |
| Amprobe VP-440 | Smallest NCVT | $31 | |
| Klein Tools NCVT-4IR | Best for HVAC | $40 |
What is a Non-Contact Voltage Tester?
A non-contact voltage tester (NCVT) is a tool that lets you check for alternating current (AC) voltage without having to touch any wires or components. It is an essential tool to make sure that the environment you are planning to work in is electrically safe.
How Does a Non-Contact Voltage Tester Work?
NCVTs contain a sensor in their tip that checks for electricity in a conductor, like a wire or a power outlet. If there is a voltage present, then the NCVT lets you know through a visual indicator (usually an LED light) and, in some models, an audible sound from a buzzer.
Non-contact voltage testers work by detecting the magnetic field that is generated by alternating current passing through a conductor. This magnetic field travels through insulation and plastic, so even at a distance the NCVT can tell whether electricity is present.
Because there is no need for you to directly touch wires, outlets or other electrical equipment, non-contact voltage sensors are one of the safest ways to check for voltage.
What is a NCVT Used for?
Non-contact voltage testers are used in any situation where you need to make sure there is no voltage present, for example when:
- Working on electrical wiring.
- Changing light bulbs.
- Checking circuit breakers.
- Working with outlets.
- Troubleshooting intercoms, doorbells or security equipment.
In short, any time you do any DIY homeowner tasks that involve AC electricity, a NCVT is useful.
Top Non-Contact Voltage Testers in 2024
The Klein NCVT-3 is the non-contact voltage tester that made it as the all-round best pick. It has several excellent features that set it aside from the competition, but despite that it does not cost a fortune.
For starters, it is a dual-range model. What this means is that it can accurately detect both high and low voltages. To make things even better, the NCVT-3 has a LED bar graph on its side that lets you know exactly what voltage you are dealing with. Both of these features take away the need for buying separate high- and low-voltage testers.
Another great feature is the built-in flashlight. When working with wiring, you can often find yourself in areas that are poorly lit, like crawl spaces, attics and areas above ceiling-mounted lights. Having extra light available in these situations is a large benefit. Unlike with other testers, the flashlight on the Klein NCVT-3 works independently of the testing function, so you can even use it as a standalone tool.
As for durability, the tool has been designed to last. Klein claims that the NCVT-3 can withstand falls from up to 6.5 feet, and it also comes with an IP67 rating. This means that the device is fully dust-sealed and can be submerged in up to 1 meter of water. So even if you intend to use your non-contact voltage tester in a wet or dirty environment, the NCVT-3 will handle it just fine.
Standout Features
- Battery life indicator
- Independent flashlight
- Compatible with tamper-resistant outlets
Technical Details |
|
|---|---|
| Voltage range | 12-48V AC and 48-1000V AC |
| Safety rating | CAT IV 1000V |
| Indicators | LEDs & audible beeper |
What We Like
- Packed with features
- Built to last
- IP67 dust- and waterproof
Could Be Better
- Fragile battery cap
If you are familiar with electric testing tools, then it should not surprise you that a Fluke product is listed as the best high-end non-contact voltage tester. Fluke products are known for their quality, reliability and accurate testing. When it comes to NCVTs, this is no exception.
The Fluke 1AC II VoltAlert comes with Voltbeat technology that is exclusive to Fluke testers. This feature continuously checks whether the circuitry and battery are working correctly. This gives you the peace of mind that when the tester is malfunctioning, you will be notified before you do any testing.
To warn you that a voltage is present, the 1AC II has both a brightly illuminating tip, and a clear beeping sound (that you can disable for use in quiet environments). This dual notification system eliminates any doubt that you miss the detection of a live wire or outlet.
This model is designed with durability in mind, but even if it breaks in its first 2 years of use, you always have Fluke’s excellent warranty to fall back on.
One of the only downsides of the Fluke 1AC II is that it does not detect lower AC voltages, because it only has a 90V to 1000V detection range. If you need to test lower voltages, then you might want to look at the Fluke 1LAC-A-II. The 1LAC-A-II comes with a 20-90V range and helps you reliably detect lower voltages. Don’t forget, these can be dangerous as well!
Standout Features
- Self-testing functionality
- Multiple indicators
- Long battery life
Technical Details |
|
|---|---|
| Voltage range | 90V-1000V AC |
| Safety rating | CAT IV 1000 V |
| Indicators | High intensity LED + sound |
What We Like
- Quick voltage detection
- Durable
- 2 year warranty
Could Be Better
- No low-voltage AC detection
The Klein Tools NCVT-2 is the cheapest non-contact voltage tester in this line-up. Despite its low price, it does its job well and is an excellent choice when you are on a budget.
The NCVT-2 features an auto power-off function that automatically turns the tool off after a period of non-use. Not only does this save battery life, but it also makes sure that you won’t find the device empty if it accidentally gets turned on.
The tool is able to detect both low voltage (12-48V AC) and standard voltage (48-1000V AC). To illuminate your workspace, it has a bright LED built in.
Standout Features
- Auto power-off
- Dual voltage notification (LED & warning tone)
Technical Details |
|
|---|---|
| Voltage range | 50V-1000V AC |
| Safety rating | CAT IV 1000 V |
| Indicators | Bright red LED and warning tone |
What We Like
- Great value
- Compact
- Easy to use
Could Be Better
- Low volume notification sound
- No low voltage detection
If you are looking for a small non-contact voltage tester without many bells and whistles, you might want to look at the Amprobe VP-440. It does not have much to offer in terms of extra features, but the device makes up for it with its compact size, reliability and ease of use.
The VP-440 is so straightforward that it does not even have an on/off button. It is simply always on. But because this tester has energy-efficient circuitry and no battery-draining features, it takes several years before you need to replace the batteries. Ideal if you are looking for a tool that you only use once in a while!
No extra features, like a flashlight or LCD bar graph, means that the device is extremely compact and you can easily carry it on you, or store it without taking up much space.
There is no buzzer on the tester either. To some, this might be a downside. But for the people who get annoyed by a beeping sound each time they check for a voltage, this can actually be a benefit.
Standout Features
- Always ready to use
- Small
- Great sensitivity
Technical Details |
|
|---|---|
| Voltage range | 50V-1000V AC |
| Safety rating | CAT III 1000V |
| Indicators | Tip lights up |
What We Like
- 'No Hassle' warranty
- US-manufactured
- Compact
Could Be Better
- No buzzer
The Klein Tools NCVT-4IR is a non-contact voltage tester with infrared thermometer designed for HVAC (heating, ventilation and air conditioning) applications. Despite this professional-sounding label, it is not just for professionals. DIY homeowners can find great benefit in this model as well.
The standout feature of this model is its infrared thermometer. You can use it to measure the temperature of anything you point it at (as long as it is not highly reflective) with a 0.1 degree resolution. The device can measure from -22 to 482 °F (-30 to 250 °C), which covers almost anything around your home, office or workshop.
To have a clear idea of the surface that you are testing, the device has a laser pointer that helps you target the measurement area. This ensures that you get accurate readings and you don’t accidentally get the temperature of the wrong part of an object.
The NCVT-4IR detects voltages from 12 to 1000V, so you can use it for high- and low-voltage testing. To ensure a long battery life, it comes with an auto power-off function that disables the device when it is not in use.
If you are more into construction than HVAC applications, then the Klein Tools NCVT-6 is also worth looking at. It is nearly identical to the NCVT-4IR, but instead of a laser thermometer it comes with an integrated laser distance meter. Perhaps a better choice if you find yourself measuring distances more often than temperatures.
Standout Features
- IR thermometer
- Backlit LCD
- Auto power-off
Technical Details |
|
|---|---|
| Voltage range | 12V-1000V AC |
| Safety rating | CAT IV 1000V |
| Indicators | Visual and audible indicators |
What We Like
- IP54 dust and water protection
- Dual indicators
- High safety rating
Could Be Better
- Fragile battery cap
Buyer’s Guide – What to Look for When Choosing a Non-Contact Voltage Tester
When buying a non-contact voltage tester (NCVT), it is important to pick the one that is best for your needs. Not all NCVTs have the same features, and because of this, a multimeter that is best for others might not be best for you.
Let’s go over some aspects of NCVTs that you should pay attention when making your purchasing decision:
Safety
Because you will be using your non-contact voltage tester around electricity, safety is the number one thing to pay attention to. You want to be safe when you use the tool and not have to worry about accidentally getting electrocuted.
Safety for electric testing equipment is classified by measurement categories, which rank from CAT I to CAT IV. CAT IV is the safest category. When it comes to non-contact voltage testers, there is no reason to go with anything less than CAT III. You can find more details on the safety categories in the buyer’s guide for multimeters.
Also important is the maximum voltage that the testing tool can deal with. For example, you might see a NCVT with a safety rating of CAT III 1000V. This tells you that the device can safely deal with voltages of up to 1000 volts.
When doing typical DIY work with electricity around the house, you will encounter voltages of around 120V (US) to 230V (EU). Three-phase voltages can be higher, up to around 400V.
Most non-contact voltage testers have a maximum voltage 600V or 1000V. With these maximum voltages you will be safe when working with standard voltages, but you also have protection against overvoltages (dangerous voltage spikes that occur when something is not working properly).
Build Quality
A non-contact voltage tester that is built to last will serve you a lot longer than one that is not. If you are looking to buy a NCVT that lasts you a lifetime or that you need to use in your day-to-day job, a high build quality is the way to go.
One of the ways you can recognize a durable non-contact voltage tester is by the following features:
- Dust tight housing. Keeping dust out of the housing of the NCVT is one way to make sure that it does not break down prematurely.
- Water resistant housing. Needless to say, water and electricity don’t mix very well. If you want to use your NCVT in wet or muddy environments, you want to make sure that no water can get in if you happen to drop the device.
- Drop test rating. It is likely that at some point during its life, a tool gets dropped. Knowing that a tool is built to withstand drops from a certain height gives you peace of mind that it won’t break easily.
Dust and water protection often go hand-in-hand, and are measured with an Ingress Protection rating. For example, the most common IP rating you will encounter is IP67. The 6 indicates complete protection against dust, whereas the 7 indicates that the tool can be submerged up to 1 meter in water without ceasing to work.
All of this is more relevant if you will use your NCVT a lot in demanding environments. But even if you will only use it for the occasional home improvement stuff, it helps to have a tool that is there for you when you need it and won’t crap out on you in the worst moment.
One non-contact voltage tester you might be interested in if you are looking for durability is the Southwire 40150N. It comes with an IP67 rating and a 6′ drop test rating.
Dual Range Voltage Detection
Many non-contact voltage testers either detect high voltage alternating current (outlets, electricity wiring, lighting fixtures, switches), or low voltage AC (doorbells, security equipment, thermostats, etc.). You can also find models with dual-range voltage detection, however.
For example, the Klein Tools NCVT-2 comes with two detection ranges, one low voltage (12-48V AC), and one high voltage (48-1000V AC). You don’t even need to manually switch between them, as this is done automatically for you.
Dual-range testing lets you use a device in a wider range of applications, and takes away the need for multiple testing devices with different ranges.
Sensitivity
Some NCVTs come with an adjustable sensitivity dial. Adjusting the sensivity lets you fine-tune the device. This helps prevent false positives (from neighbouring wires, for example), but also makes sure that the voltages that you do want to detect are being seen by the tool.
Size
If you want to carry your non-contact voltage tester with you on the go, or always have it within reach in your pocket, then it is a good idea to go with a pen-style tester.
These models are small, portable and often come with a pocket clip that allows you to clamp the device onto your pocket.
Price
A good non-contact voltage tester does not need to cost much. You can find reliable models for about $20. But if you want it to come with extra features, you should be prepared to spend a bit more.
Whichever model you decide to buy, make sure that it has all the functionality you need, and that the device meets the required safety standards. It is not worth saving money if the tool does not meet your needs, or if it does not do a good job at keeping you safe.
Testing Functionality
If you only need to check for the presence of AC voltage, then a non-contact voltage tester is a great option. But if you want to test for more things, however, it is a better idea to get a multimeter instead.
Multimeters let you test and measure both AC and DC voltage, measure current, check for continuity, and a whole lot more. They do cost more than NCVTs, but are still a bargain for all the functionality they give you.
Battery Life
Non-contact voltage detectors typically work on either AAA batteries, or watch batteries. You aren’t able to recharge these, so it is important that the NCVT makes the best use of the charge that it has available.
Some of the better NCVTs, like the Fluke 1AC II, come with low-power circuitry that limits the amount of current drawn from the battery, an auto-off function that makes sure that the device doesn’t stay on until the batteries are drained, and sometimes even a battery check function.
All these functions ensure that the device is always ready for you when you need it, and you won’t need to find a fresh set of batteries before you can continue with the project you are working on.
Voltage Notification
A non-contact voltage tester that is great at detecting voltage, but doesn’t have a clear way of letting you know, is useless. So when buying a NCVT, it helps to check the notification methods that the device has.
The most common way of voltage notification is an LED that is placed in the tip of the device. When the tip is held in the proximity of a magnetic field (like when a voltage is present), the LED lights up.
Another way the device can let you know that it has found a voltage, is through sound. Some models come with an incorporated buzzer that creates an audible noise when the device is in the presence of a magnetic field.
The more methods of notification, the less risk of misinterpreting the results of the voltage test. Look for a non-contact voltage tester with bright notification LEDs and a clear, audible buzzer.
Additional Functionality
Some NCVTs come with additional functions that can prove practical in certain situations. The function you will encounter most often when deciding which non-contact voltage tester to buy is a flashlight. Certainly useful if you find yourself working in low-light situations.
Other functions you might come across are an infrared thermometer, like on the Klein Tools NCVT-4IR, and even a laser distance meter, like on the NCVT-6. This type of additional functionality makes these tools great options for HVAC applications and construction work.
Brand
In general, I recommend sticking to well-known and reputable brands. But this is especially the case when it comes to tools that will be used around electricity. Safety is extremely important in this situation, and trustworthy tools are essential.
Reputable brands for non-contact voltage testers are Fluke, Klein Tools, Gardner Bender, Amprobe and Southwire. Going with a device of one of these brands is a safe choice.
As usual in the Buyer’s Guides on this site, I have left out the off-brand tools that are a waste of your time and money.
Are NCVTs Safe?
Yes, NCVTs are very safe. As long as you are using a quality tester that is properly insulated and has no exposed metal or conductive elements, you do not need to worry about being shocked by the tool.
If the tool is structurally damaged in any way, it is better to discard it and replace it with a new unit. Better safe than sorry.
Do Non-Contact Voltage Testers Work on Direct Current?
They do not. NCVTs work by detecting the electro-magnetic field that is generated by alternating current (AC). Direct current (DC) typically does not create the same electro-magnetic field, and therefore NCVTs are not a good option for detecting DC.
Similarly, if you work with alternating current that travels through shielded cables, you will have trouble detecting it with a NCVT. These cables have electromagnetic shielding that help block the electro-magnetic field.
Is a Voltage Tester the Same as a Multimeter?
No, there are some big differences between voltage testers and multimeters. Voltage testers typically only test whether a voltage is present or not. If you want to know how much voltage is present in a circuit, you will need to use a multimeter instead.
Another difference between the two is that non-contact voltage testers do not require you to touch any wires or terminals. When working with a multimeter, this is something that you need to do. In order to get a reading you need to connect the two probes to the actual circuit.
Multimeters also have a lot more functions than voltage testers, hence the “multi” in multimeter. You can use them for testing voltage, current, resistance and sometimes even capacitance, temperature, decibels and more.
How Much Does a Non-Contact Voltage Tester Cost?
You can expect to spend a minimum of $15-$20. Depending on any extra features you want, the price can increase. You could go for a model that costs less than $15, but then you are likely to run into quality and safety issues.
Conclusion
Safety is the most important aspect in working with electricity, and a non-contact voltage tester is a tool that helps you with that. No matter if you are a DIYer or an experienced electrician, it is essential to be careful and to not take any unnecessary risks. By doing so, you can deal with minor electrical repairs and fixes around the home yourself.
If you happen to be a homeowner that wants to fix minor electrical issues, then the Klein Tools NCVT-3 is the tester I recommend. Not only does it detect high- and low-voltage alternating current, but it also has a built in flashlight that you can use in dimly lit areas. Aside from around the house, it is also an excellent fit for commercial and residential applications.
Professionals that need a non-contact voltage tester don’t need to look any further than the Fluke 1AC II VoltAlert. It comes with the durability and reliability that you can expect from Fluke. It works flawlessly for voltages between 90V and 1000V.
If you also need to detect lower voltages (20-90V), you can complement it with the Fluke 1LAC-A-II.
For people on a budget, the Klein Tools NCVT-2 is one of the best options. Despite having half the cost of the other non-contact voltage testers in this buyer’s guide, it still provides adequate testing. And with its dual (visual & audio) notification system and auto-power off function, it provides excellent value.
If you need to work on projects that involve more than just detecting the presence of a voltage, a digital multimeter might be a better fit for your needs. Aside from detecting a voltage, it can measure the value as well. Digital multimeters can also measure amperage, resistance and a variety of other electrical properties. If you ever plan on doing more intermediate or advanced electrical work, you can’t go without one.
