Here we are using two switches namely S 1 and S 2 to select the desired meter. Actually it is a voltage source. We may use additional range-selector switches to choose particular range required in reading amperes volts and ohms.
Digital Multimeter Circuit Using Pic Microcontroller Analog To Digital Converter Pic Microcontroller Multimeter
We use a rectifier to measure an AC voltage or current with the multimeter.
Block Diagram Working Principle and Construction of Digital Multimeter in Digital Instruments Video Lecture of Analog and Digital Instruments Chapter in Sub.
When such a meter is connected in the circuit to measure voltage it will draw negligible current thus will measure the correct voltage. The sensitivity of a multimeter varies from 8k ohm per volt to 20k ohm per volt. Thanks for reading about the analog multimeter working principle. Analog multimeters work based on the deflection of a needle from its zero position point.
During a measurement one needs to read the correct value just under the needle.
The main part of an analog meter is a galvanometer that consists of a small winding. The winding can rotate about a pin and a needle is attached to it. The following figure represents the digital multimeter block diagram with all the functional blocks. Digital Multimeter Block Diagram The auto-ranging digital multimeter DMM only requires you to choose your electrical quantity you are attempting to measure make sure you are properly placing your leads into the correct terminals and.
A analog or analogue multimeter is one of the trusty workhorses of the electronics test industry.
Analogue multimeters have been in use for very many years and sometimes go by the name VOA as a result of the fact that they measure volts ohms and amps. It may be cheaper to purchase an inexpensive analog meter and disassemble it for the meter movement alone. Although the thought of destroying a working multimeter in order to have parts to make your own may sound counter-productive the goal here is learning not meter function. The meter will read one of three things000 1 or the actual resistor value.
In this case the meter reads 097 meaning this resistor has a value of 970Ω or about 1kΩ remember you are in the 20kΩ or 20000 Ohm mode so you need to move the decimal three places to the right or 970 Ohms.
If the multimeter reads 1 or displays OL its. A multimeter or a multitester also known as a VOM volt-ohm-milliammeter is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter can measure voltage current and resistance. Analog multimeters use a microammeter with a moving pointer to display readings.
Digital multimeters DMM DVOM have a numeric display and may also show a.
Working Principle of Digital Multimeter. As shown in the block diagram in a typical Digital multimeter the input signal ie ac or dc voltage current resistance temperature or any other parameter is converted to dc voltage within the range of the ADC. If youre doing any kind of electrical workno matter what the application isone of the best tools you can have at your disposal is a multimeter. If youre just getting started heres how to use one and what all those confusing symbols mean.
Multimeter is a measuring instrument.
It can be used to measure voltage current and resistance. An analog meter Figure a moves a needle along a scale. The function of the meter can be changed by switching the dial. Analog multimeter shown in the figure is cheap but difficult for beginners to read accurately.
Most modern multimeters are digital.
Working Principle of Voltmeter. Its Working is based on the principle of Ohms law. Ohms law states that Voltage across a resistance is directly proportional to the current passing through it. Any basic meter has a potential difference across its terminals when a full-scale current flows through it.
Block Diagram of ADC The analog signal is first applied to the sample block where it is sampled at a specific sampling frequency.
The sample amplitude value is maintained and held in the hold block. It is an analog value. Make sure that maximum analog input voltage should be less than 25V DC. Connect a digital multi meter at the Input terminals of the voltage sensor.
Now switch on the board supply.
Now observe both LCD and digital multi meter both displays the same voltage or very similar voltages. If possible try to slowly vary the analog input voltage. The basic circuit of one type of analog electronic voltmeter is illustrated in figure 1. This particular circuit is made up of three stages.
An input attenuator an electronic amplifier and an electromechanical voltmeter stage.
Electronic Voltmeter Circuit Diagram Block Diagram. Working Principle of digital voltmeters. From the above block diagram t he voltage to be measured is given to the input signal present in the circuit diagram. And next to this signal is processed onto the pulse generator which generates a train of rectangular pulses by using both analog and digital techniques.
1 Digital Voltmeter and Multimeter.
How does a Digital Voltmeter Work. An AD converter or ADC Analog to Digital Converter converts an analog voltage sample and returns a binary number that describes the sample. Basic Block Diagram of Digital Voltmeter. Working Principle of Digital Voltmeter.
The block diagram of a simple digital voltmeter is shown in the figure.
Explanation of various blocks Input signal. It is basically the signal ie. Voltage to be measured.
