Failure to take proper precautions when working with electrical components can result in serious injury or death. Follow the manufacturer's instructions for all tools, and wear appropriate safety gear. Check to see if you need a permit. Observe applicable building and electrical codes. Contact a licensed electrician if you have any doubts or questions about the connections or if your home's wiring doesn't appear compatible with the changes you're making.
Multimeters
A multimeter, which is sometimes called a volt-ohm meter, is one of the most common electrician’s tools. Essentially, it's used to test for and measure electrical voltage. Electricians use these tools to perform a variety of tasks, such as measuring the voltage of batteries and detecting faults and other electrical problems. There are two main types of multimeters, which are differentiated by the kind of readout they offer: digital multimeters and analogue multimeters. These meters can be used by DIYers for a variety of projects around the home. For more information, see our DIY Basics video: How Do I Use a Multimeter?
Digital Multimeters
One of the most common types of multimeters found in stores is the digital multimeter. These electrical testers come with a variety of features and settings and are most easily recognized by their digital display screens, which are much easier to read than some other types of meters. The price of these devices can vary greatly depending how advanced the features are, but multimeters with a digital readout typically cost more than analogue models.
Analog Multimeters
Analog multimeters measure current or amperage using a moving needle rather than a digital display. Analog meters are often the most economic option, but they do come with a couple of drawbacks. You must take care when using them as their internal mechanical parts are delicate and can be damaged if the tool is dropped. This type of meter can also be more difficult to read for less-experienced DIYers. Analog meters also may not read as accurately as digital ones when used as a voltmeter, but the moving needle may be better for slow-voltage detection.
Auto-Ranging Multimeters
Auto-ranging multimeters have the added benefit of automatically adjusting their internal range to help locate the right current, resistance or voltage of the electrical component you’re testing. This handy feature is typically found on higher-end testers.
Clamp Meters
As the name suggests, a clamp meter allows electricians to measure the current in a circuit by clamping it around a cable, wire or other conductor. This device allows professionals to get an accurate measurement without disconnecting or cutting the power to any wires, unlike with probe-style testers. Clamp meters come in basic models or advanced models with additional features, such as voltage, continuity and resistance measurement capabilities.
Non-Contact Voltage Meters
Non-contact voltage testers are an economical choice for simple DIY projects, such as replacing a light switch, where the user only needs to know if a current is present. These devices typically beep or light up if voltage is detected but don't offer any advanced measurements.
Other Types of Test Meters
- Moisture meters measure the amount of dampness present on a surface such as wood or concrete. This device is useful when trying to diagnose the source of mold and moisture problems in a home.
- Digital thermometers measure the temperature of an object or area and offer a precise readout for situations when accuracy is important.
- Infrared thermometers use infrared light to measure the temperature of an object or area without making direct contact with it.