Multimeter, types, uses

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What is a multimeter?

It is an electronic tool widely used by every electrical and test equipment engineer. The voltage, current, and resistance—the three primary electrical properties—are mostly measured with a it.
It has multiple functions such as ammeter, voltmeter and ohmmeter. Positive and negative indicator arrows are located atop a digital LCD screen on this handheld device. The wiring in your home, electric motors, and power supply may all be tested using this device.

Parts:

It consists of three parts:

1)Screen
2)Selection button
3)Ports
The display usually has four digits and the option to show a minus sign. Some have backlit displays for better viewing in low light conditions.

They can be configured to read a number of different parameters, including current in milliamps (mA), voltage (V), and resistance (ohms), using the dial.

Two sensors connect to two ports on the front of the device.The "ground" or "-" circuit is generally always where the "common" signal, abbreviated as "COM," is attached. The COM sensor is usually black, but there is no difference between the red and black sensors other than color. 10A is a special port used when measuring high currents (more than 200mA). The red probe is typically attached to the port designated as mAV. This port allows you to detect voltage (V), resistance (Ω), and current (up to 200mA). A banana plug that connects to a multimeter is located on the end of the probes. This metre is compatible with any banana-plugged probe. This allows the use of different types of probes.

Types:

Multimeters come in a variety of varieties, each with unique features and applications. Here are a few popular multimeter types:

Analog:

Analogue multimeters display measured values using a mechanical pointer and dial. Due to their simplicity and usability, they are still used by certain professionals as the classic form of multimeter. Resistance, voltage, and current can all be measured with analogue multimeters.

DigitalDMM):

DMM are the most commonly used type today. They offer digital readouts on an LCD or LED display, which makes them precise and simple to read. Electricity can be measured in a number of ways, including voltage, current, resistance, capacitance, frequency, and temperature. They might also come with extra capabilities like data logging, auto ranging, and connection options for data transfer to a computer.

Clamp Meter:

It is designed to measure electrical current without having to disconnect the circuit. It has a hinged "clamp" that can be clamped around a conductor to measure the current flowing through it. Clamp meters are typically used in applications where it is not possible or safe to break the circuit to insert a standard multimeter.

Automotive:

Specialised multimeters created specifically for automotive purposes.They can measure various vehicle-specific electrical parameters, such as battery voltage, engine speed, deceleration angle and temperature. These multimeters frequently come with extra features like diode tests, duty cycle measurements, and settings specifically for automotive systems.

Desktop:

Bench multimeters are more complex, bigger made for lab or business application. Generally speaking, they are more accurate, precise, and offer more measuring choices than portable multimeters. Large screens, several input channels, and sophisticated networking options are common features of bench multimeters.

HVAC:

HVAC (Heating, Ventilation, and Air Conditioning) are specialized multimeters designed for HVAC professionals. They have specialised features and measurement ranges made just for HVAC applications, such as temperature measurement, testing for motor run/run capacitors, and testing for flame detectors.

Fluke MM:

You can choose from a number of collaboration features for your Fluke DMM. It usually contains a large screen and is used to measure voltage and electrical resistance.The measurement of humidity, duty cycle, pressure, frequency, and other variables can be done with a variety of devices with extensive features. It is one of the most widely used and well-known instruments.

Currents, volts, and other electrical units can all be calibrated using this particular sort of multimeter. Fluke multimeters are protected against voltage spikes. This is a small handheld device used to measure voltage, current and test diodes. The multimeter has multi-selectors for selecting the desired function. For the majority of measurements, the Fluke MM chooses a range automatically. This means you don't need to know or determine the amplitude of the signal to get an accurate measurement, it is sent directly to the correct port for the desired measurement. The fuse is protected from damage if connected to the wrong port.

Functions:

These tools can read different values depending on the model. Therefore, the main types of multimeters are mainly used to measure current, resistance, voltage, continuity test, and the entire circuit can be tested as follows.

Resistance in ohms
Capacity in farads
Temperature in Fahrenheit/Celsius
AC voltage and current
Henry's inductance
DC voltage and current
Frequency in Hz
Conductivity at Siemens
decibels
Duty cycle

Different probes or accessories for specific multimeter types, such as those for measuring acidity, light level, alkalinity, wind speed, and relative humidity, may also be included.

Difference between analog and digital:

Analog multimeter	Digital multimeter
Limited electrical quantities, such as resistance, voltage, and current, are measured using an analogue multimeter.	The digital multimeter is used to calculate various electrical quantities such as voltage, current, capacitance, resistance, diode and impedance values, etc.
Size of the analog MM is larger.	Digital MM size is more compact.
Frequency range up to 2kHz.	The frequency range is higher than that of analog.
This gauge gives a reading on the scale next to the pointer.	This counter provides a numerical reading on the LCD screen.
They are manually calibrated.	They calibrate automatically.
The design is simple.	The use of parts like electronics and logic makes the design complex.
They are less accurate due to parallax errors and incorrect pointer readings.	They are very accurate.
The maximum AC frequency to be calculated is lower.	The maximum AC frequency to be calculated is higher than the counter.
No ADC is required to view the measurement.	An ADC is required to view the readings.
Input impedance is unstable.	The input impedance is stable.

When the polarity is reversed, the multimeter's needle tries to rotate anticlockwise.	When the polarity is switched, this multimeter displays a negative value.
They are cheaper.	They are expensive.
The output of this counter cannot be connected via external equipment	The output of these meters can be connected via external equipment.
It measures current using a galvanometer.	Viewing the readings requires an ADC.
It has less electrical noise.	It has more electrical noise.
Allows accept only one input signal per operation.	Multiple input signals are accepted, and users can choose the desired signal from the variable display.

Advantages and disadvantages of digital multimeters:

The advantages of a digital multimeter are as follows.

This ensures an automatic o/p display.

The meter's measurement results can be synchronised with a PC, recorded, and kept in memory.
Includes automatic polarity functions
The accuracy of the meter readings cannot depend on the battery charge
This ensures accuracy
Resistance to mechanical damage.
Multifunctionality
Zeroing not required
The measurement accuracy is high
Intervals between measurements can be chosen manually or automatically.

The disadvantages of a digital multimeter are the following:

Expensive compared to similar.

The measurement fluctuations cause this multimeter to malfunction.

It can be difficult to find one that exactly fits your needs.

Advantages and disadvantages of an analog multimeter:

The advantages of an analog multimeter are as follows.

Possibility to take measurements at temperatures below -30°C
It does not require the use of energy from a fixed power source when measuring current and voltage.
When high accuracy is not required, a fast operation with a large number of measurements can be performed.
All measurements can be easily performed with this tool.
You can see the signal strength

The disadvantages of an analog multimeter are the following:

These gauges are great.
it is expensive
Voltage polarity not recognized
They are sensitive to vibration or shock.

The pointer is unreliable for measuring voltage at frequencies higher than 50 Hz and moves slowly.
Not true because of the influence of the Earth's magnetic field.
An unexpected signal change can be detected more quickly with an analog multimeter than with a digital multimeter.
They are sensitive to vibration, mechanical damage.
The input impedance is lower, so there is more error when measuring a lower voltage.

Types of multimeter applications:

Applications of types of multimeters mainly include various electrical and electronic component testing projects, and are also used in various measurement applications in multimeters.

Multimeter type applications mainly include various electrical and electronic component testing projects, and are also used in various multimeter measurement applications.

Temperature and environmental conditions

cheap weather station
DMM internal temperature
Voltage measurement

Measurement of high and low direct current
Peak-to-peak and average DC current measurement
Current measurements

Measurement of direct current
True RMS AC
Resistance measurement

micro ohmmeter
DC resistance measurement
DC resistance measurement
Time and frequency measurement

fast frequency
Time measurement