Digital Multimeters - Voltage, Current & Resistance Testing

Digital Multimeters for Electrical Testing

Digital multimeters are essential diagnostic tools for measuring electrical values including voltage (AC/DC), current, resistance, and continuity. These handheld testing devices provide accurate digital readouts on LCD displays, making them indispensable for electricians, technicians, and DIY enthusiasts.

Key Measurement Functions

Modern digital multimeters measure multiple electrical parameters in a single device. Standard functions include AC/DC voltage testing up to 600V or 1000V, current measurement in amperes, resistance testing in ohms, and continuity checking with audible beepers. Many models feature auto-ranging capabilities that automatically select the appropriate measurement range.

Display and Accuracy Specifications

Digital multimeters feature LCD screens with count ratings typically ranging from 2000 to 6000 counts, determining measurement resolution. Accuracy ratings are expressed as a percentage of reading plus digits (e.g., ±0.5% + 3 digits). Backlit displays improve visibility in low-light conditions, while hold functions freeze readings for recording.

Safety Ratings and Categories

CAT (category) ratings indicate the maximum voltage and environment where a multimeter can safely operate. CAT II is suitable for household electronics, CAT III for distribution panels and fixed installations, and CAT IV for utility connections and outdoor applications. Proper safety rating selection prevents electrical hazards.

Additional Testing Capabilities

Advanced digital multimeters may include diode testing, capacitance measurement in farads, frequency measurement in hertz, temperature sensing with thermocouple inputs, and transistor testing. Non-contact voltage detection and true RMS measurement for accurate AC readings are valuable features for professional applications.

Build Quality and Portability

Durable housings with rubber holsters protect against drops and impacts on job sites. Test lead storage, kickstands for hands-free viewing, and compact designs enhance portability. Battery life varies by model, with most using 9V or AA batteries providing hundreds of hours of operation.