Electrical and electronic engineering students, engineers and technicians use various measuring devices to check various electrical quantities in a circuit, such as voltage, current, continuity, power, etc., and to check and test various electronic components, such as diodes, transistors, relays, capacitors, resistors, etc. Multimeters, which are capable of performing different tests and measurements, are used in laboratories and industries for repair and troubleshooting of electrical equipment and devices.
What is a Multimeter?
A multimeter is an electrical measuring instrument used to measure electrical parameters such as voltage, current, resistance, etc. It can measure "multiple" electrical quantities, depending on the type of multimeter.
They are handheld devices that vary in size, precision, and accuracy. They are primarily used by electricians, engineering students, and hobbyists to troubleshoot electrical equipment and circuits.
Working of a Multimeter
Multimeters can be either analog or digital. But the working process is the same for both types of multimeters.
It has a dial for selecting the desired measurement. It has multiple measurement symbols written on it. Rotate the dial to select the measurement. It also allows you to select the appropriate measurement range. Some meters have an auto-ranging feature.
It has two probes, black and white. The black probe always plugs into the black "COM" or common port, while the red probe plugs into one of the other red ports depending on the measurement.
The probes are used to connect the meter to the circuit. The multimeter's internal circuitry measures the selected parameter and displays the reading on an LCD display or scale.
However, the considerations and configurations used to connect a multimeter to a circuit or component vary depending on the type of measurement.
Types of Multimeters
Analog multimeter
An analog multimeter is the oldest form of multimeter. It has a needle that rotates along a scale. They are cheap but difficult to read. However, they are more sensitive than a digital multimeter. It can sense even small changes in the reading.
Digital Multimeter
A digital multimeter or DMM measures the amount of electricity and displays it on an LCD screen. It calculates the readings digitally and displays it on an easy to read digital screen. On the other hand, an analog multimeter displays the readings without any calculations and therefore has a fast response time.
