A digital multimeter is an indispensable tool for testing, diagnosing, and troubleshooting electrical circuits, components and devices and works by measuring two or more electrical values—principally voltage (volts), current (amps) and resistance (ohms). It is a standard diagnostic tool for technicians in the electrical/electronic industries and is a must-have for any toolbox. Digital multimeters long ago replaced needle-based analog meters due to their ability to measure with greater accuracy, reliability and increased impedance.
Things to consider when buying your Digital Multimeter (DMM)
DMM Specifications
Choose a digital multimeter with a higher main voltage than is required to operate electrical devices that you want to observe the readings for
It is important not to use the multimeter above the current range it can withstand
When buying higher-end digital multimeters, check whether it provides the true RMS value
DMM Accuracy
Accuracy is defined as the maximum permissible error limit in the observed readings.
DMM Resolution
DMM Resolution is defined as the number of digits up to which the signal strength can be measured. It is the measurement of the change in the output signal, as a result of the smallest fluctuation made in the input signal.
Input Impedance
If you need to measure more sensitive electronic devices, accurate measurements can be attained by choosing a multimeter with high input impedance
Frequency Measurement
Some DMMs are capable of measuring the frequency and in turn monitoring voltage and current within a frequency range. If your device is powered by steady AC voltage, ensure that it maintains the correct frequency.
Temperature Measurement
If you have frequent temperature monitoring needs, a multimeter with a dual differential temperature function allows you to measure two temperatures simultaneously.