Types of Electrical Test Devices: Their Features & Functions

Electrical Technicians Electrical technicians use many types of electrical test tools. Each piece of equipment has a distinct function in operations that involve electricity. Here’s a quick guide to the most commonly used electrical test devices, along with their features and uses.


A voltmeter is used to measure the voltage difference between two points. This tool can measure the amount of voltage that ranges from millivolts to hundred of volts. Also, it can show the current’s polarity. Positive and negative values you can read from the voltmeter represent the current’s direction. Electricity flows from positive to negative.

This tool comes in two types: the older analog version and the digital type. While digital voltmeters are costlier than its traditional counterpart, they provide better features.


An oscilloscope is a tool used to measure the changes in voltage over time. This device has a screen that displays a graph showing voltage change. It is an excellent tool for determining the frequency of digital signals or AC voltages. This tool is highly useful in repairing electronics.


An ammeter is designed for measurement of electric current or amperage. Note that the voltage that is measured by a voltmeter is different from current. Current is defined as the rate at which electric charge passes a circuit’s certain point.

According to dealers of electrical test tools, ammeters can measure from the millamp level to around 10 amps. Amperage higher than that allows an easier measure of the current-generated electromagnetic field. In such situations, technicians use an ammeter that is clamped around the wire.


A multimeter is a tool that combines the features and functions of a voltmeter and an ammeter. The typical digital multimeters you can find in the market are also designed to measure continuity and resistance. You can use most of them to check transistors, batteries, and diodes.

These are only some of the different types of electrical test devices. Thanks to modern technology, manufacturers are able to improve the features and boost the functions of these tools. In effect, technicians and even everyday homeowners can benefit from faster, safer, and more convenient electrical operations.