Whether you happen to be a professional electrician, a small appliance repair person or a safety-conscious homeowner, the purchase and use of a multimeter can save you extra time, stress and money. A multimeter helps determine the amount of current and voltage in electrical circuits and wiring.
A compact and dependable unit in your toolkit like our top choice, the Fluke 115 Compact True-RMS Digital Multimeter, means you can get a quick and safe read on a breaker, broken outlet or dead battery whenever you need it.
Even a minor shock can be dangerous, so using a quality multimeter is vital for any project involving electricity. The consequences can range from mild shock to serious injury, and even death. Anyone working with electricity should take all due care and caution when dealing with potentially live wires, especially nonprofessionals.
While the importance of proper safety around electricity cannot be overstated, it is also important that a multimeter can test most any projects, from electronic hobbyist projects to electrical installations.
Digital multimeters are one of the most common units available to everyday consumers. The built-in digital screen makes the numerical output easy to read. While less commonly used by the everyday hobbyist, analog multimeters utilize a needle indicator that points to the appropriate number on the display. They usually have fewer features, but provide instant readings and are less expensive than their digital counterparts.
While not generally familiar to the common layperson, the IEC or International Electrotechnical Organization, is the governing body that regulates and releases technical standards for all kinds of electronic and electrical equipment. However, the most important thing that you need to know is whether the multimeter you intend to purchase has the appropriate rating for the work you intend to do.
IEC categories or CATs are rated I through IV (1-4), with each representing a new level of electrical power and potential risk. CAT I multimeters are typically used to test electrical circuits in PCs and laptops, while CAT II multimeters are ideal for testing plug-in loads and standard mains sockets, including power tools and washing machines. CAT III multimeters are used for testing industrial equipment and building construction, whereas CAT IV multimeters are commonly used for testing components of the national electrical grid.
Given that most typical consumers will hopefully never have the need to test if their local transformers are working properly, purchasing a CAT II or III multimeter should be more than sufficient for most people’s purposes.
While you might be eager to use your brand new multimeter to test every electrical connection in the immediate vicinity, it is important to be aware of the capabilities of the multimeter. If you don’t know what the standard voltage is for the device or circuit you’re testing, you may essentially be taking a stab in the dark with pointed probes.
The vast majority of multimeters have convenient central selector dials to easily switch between voltage ranges to ensure an accurate and speedy reading. Even better, most multimeters are already set for the ranges of commonly used and tested equipment powered by both AC and DC current, including DIY projects, automobile stereo, household wiring and commonly used computer components.
While the term may be unfamiliar to some, an ohm is the standard of measurement for determining the resistance of a material to electricity. Naturally, the more resistant a particular object or material is, the harder it is to transmit electricity. This can be very useful when determining if a connection is working properly or not.
For example, an electrical connection in good working condition will register as having little to no resistance, whereas an interrupted or otherwise severed connection will display an “infinite” level of resistance. Given that there is no way to pass electricity safely through a broken or damaged connection, this particular setting can save you a lot of time and trouble.
Depending on your desired features along with budgetary considerations, a quality multimeter can cost $21-$186, and sometimes more.
A. Just like any piece of electrical equipment, multimeters are prone to the effects of aging circuitry. If you repeatedly experience errors with multimeter readings that aren’t corrected through diagnostic testing, it might be time to start searching for a replacement.
A. Yes, especially if you fail to give the unit proper maintenance, such as replacing broken leads. Furthermore, any defective component or exposure to voltage beyond its IEC CAT can also lead to potential shocks.
What you need to know: This is a robust and reliable multimeter for use in general construction and minor industrial setups.
What you’ll love: This unit is CAT III 600 V safety-rated and can withstand high operating and storage temperatures. It features a large white LED backlight for testing in areas with poor lighting and can be used to perform diode tests, as well as testing for continuity, capacitance and frequency.
What you should consider: Some users have reported that they can only read the unit’s display at a specific angle.
Where to buy: Sold by Amazon
What you need to know: Affordable and dependable, this multimeter is great for automotive testing and commercial applications.
What you’ll love: This unit includes professional features such as Auto-Ranging capability and True RMS for measuring AC voltage, and offers an impressive array of tests.
What you should consider: Users have reported issues with measurement consistency and short testing leads.
Where to buy: Sold by Amazon
What you need to know: This is an excellent multimeter for testing all kinds of commercial and consumer electronics.
What you’ll love: This unit beeps when the digital multimeter’s probes are placed close to the object being measured (non-contact voltage alert). It can perform measurements of both AC and DC amps and voltage, as well as capacitance readings, continuity and diode testing, resistance, and measures frequency and duty-cycle. It also provides over-range protection for all modes.
What you should consider: Users have reported issues with the unit failing within months of purchase and providing faulty readings.
Where to buy: Sold by Amazon
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Daniel Martin writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.