Digital multimeters are electrical measuring tools that measure electrical (or non-electrical) quantities such as AC and DC voltage, resistance or current. There are used in routine maintenance of electrical equipment, when laying down new electrical wiring, etc. They can serve as parameter testers for network components, but also as testers or thermometers use to check heating components. Digital multimeters vary depending on their functions and measuring range and accuracy.
Continue
Digital multimeter measuring range
Determines the extent to which a multimeter is able to measure different quantities. Make sure to carry out measurements only in the range specified by the manufacturer, otherwise you risk damaging the device.
How accurate are they?
Modern digital multimeters have a measuring accuracy of 1 to 0.25%, which means there is some margin for error, but it’s so small that measurements have sufficient probative value. Conversely, laboratory devices, designed to provide most accurate measurements possible, have a margin of uncertainty of 0.1% or less. With older analogue multimeters, expect an accuracy of 0.5-2%.
Standard digital multimeters can measure
- Voltage (volt, V), the electric potential difference between two points.
- Electric current (ampere, A), i.e. the rate of charge flow past a given point in an electric circuit over time.
- Electrical resistance (ohm), the ability of an electric conductor to pass electric current.
- Electrical capacitance (farad, F), the amount of charge required to increase a conductor’s electric potential by unity.
- Frequency (hertz, Hz), i.e. the number of cycles per second in an alternating current.
- Conductivity (siemens, S), i.e. the ability to conduct electric current.
- Inductance (henry, H), the ability to generate a magnetic field.
Other digital multimeter functions and features
- Automatic range change - the device automatically selects the measuring quantity range. This ensures more accurate results.
- MIN/MAX - records the minimum and maximum values during the measurement, so you have an overview of the measuring range.
- Overload protection.
- Diode tester.
- Measuring temperature, humidity, light, sound – a multimeter can also serve to check potentially heating components.
- Backlit display allows you to work in the dark.
- Extra lamp for work in the dark.
- Audible warning when certain values are exceeded.
- Automatic shut-off when left idle to save battery life.