Here we are using two switches namely S 1 and S 2 to select the desired meter. The basic principle behind digital multimeters is the Analog to digital converter because without this we are not able to convert the analog output into digital form. We may use additional range-selector switches to choose particular range required in reading amperes volts and ohms.
How To Use A Multimeter Multimeter Electrical Engineering Projects Electrical Projects
We use a rectifier to measure an AC voltage or current with the multimeter.
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.
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. An AVO Mk 8 Analogue Multimeter dB scales and ranges.
Some analogue multimeters will have a dB scale on them.
The analogue meter is not a power meter and it also cannot directly compare readings to provide a ratio. The readings are typically used for looking at the standard line audio signals and the decibel readings are relative to 1mW into 600Ω. Block Diagram Working Principle and Construction of Digital Multimeter in Digital Instruments Video Lecture of Analog and Digital Instruments Chapter in Sub. 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. Figure 1 shows a block diagram of a typical meter movement where a moving coil is deflected against a set of calibrated springs within the magnetic field of a permanent magnet when a current is applied to the coil. It should be noted that an analog meter is an electro-mechanical device and will display an average reading. The model recommended in the parts list is sold as a voltmeter with a 0-15 volt range but is actually a milliammeter with a range multiplier resistor included separately.
It may be cheaper to purchase an inexpensive analog meter and disassemble it for the meter movement alone.
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. Block diagram of analog multimeter electronic circuit schematics. Glossary of key terminology used in printed circuit board.
Connect analog output signals to a daq device national.
Multimeter clock simpson 260 alan parekhs electronic. 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 above block diagram consists of two blocks. Half wave rectifier and DC voltmeter. We will get the corresponding circuit diagram just by replacing each block with the respective components in above block diagram. So the circuit diagram of AC voltmeter using Half wave rectifier will look like as shown in below figure.
A multimeter is a handy tool that you use to measure electricity just like you would use a ruler to measure distance a stopwatch to measure time or a scale to measure weight.
The neat thing about a multimeter is that unlike a ruler watch or scale it can measure different things kind of like a multi-tool. Most multimeters have a knob. The unit shown above is typical of a handheld analog multimeter with ranges for voltage current and resistance measurement. Note the many scales on the face of the meter movement for the different ranges and functions selectable by the rotary switch.
This work is on an analogue multimeter.
A multimeter is a tool basically used to measure current voltage and resistance. An analog multimeter is the most commonly used instrument by technicians and engineers in the laboratory as well as other repair works. 31 BLOCK DIAGRAM OF THE SYSTEM 32 CIRCUIT DIAGRAM 33 CIRCUIT OPERATION AND. 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. 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. The block diagram shows the comparator circuit reference control and Hi Limit LED added to the original virtual instrument design. The analog voltmeter VI can be obtained at the bottom of the article in the Download Code box. Block diagram of Digital multimeter.
