Design and construction of digital multi meter using pic. Multimeter has multi functionalities like, it acts like ammeter, voltmeter and ohmmeter. Digital multimeters combine the testing capabilities of singletask metersthe. Connect the red test lead to the vma probe socket and the black lead to the com probe socket max 10a. Power dissipation effects when measuring resistors designed for temperature measurements or other resistive devices with large temperature coefficients, be aware that the multimeter will dissipate. A digital multimeter dmm is a test tool used to measure two or more. Some common quantities are such as inductance, capacitance, temperature, frequency, speed and rms values. How can the working principle of digital multimeter be. A digital multimeter dmm may look complicated and intimidating at first glance, but once you understand the display, dial, and port panel, youll have a better grasp of dmm basics.
Digital multimeters dmm, once called voltmeters, have been. B a digital voltmeter for which you will use an adc chip, the adc0831 to measure voltages. It allows the user to set the multimeter to read different. At the end of this article you will learn how to measure voltage with multimeter, measure dc current, check for. The meter with holster that is giving the main body, though downsized, high resistance against the shock of a drop. In general, stick to dc circuits the settings on the multimeter with straight lines, not curvy lines. Digital muti meter only this meter is a handheld and battery operated digital multi meterdmm with multi function. The standard and basic measurements performed by multimeter are the measurements of amps, volts, and ohms. Multimeter notes in the lab we will use a digital multimeter dmm to measure resistance, voltage, and current in our circuits. This thesis describes the design and construction of digital multimeter. General the instrument is a pocket digital multimeter, which is used to measure dcv, acv, and dca, resistance, diode and continuity test. Not all multimeters have a dedicated continuity mode. Keysight truevolt series dmm operating and service guide.
The basic building blocks of digital multimeter are several aid converters, counting circuitry and an attenuation circuit. Simple instructions on how to use a digital multimeter. The multimeter tests continuity by sending a little current through one. Switched range multimeters have the standard v, a and. An introduction to the digital multimeter wisconline oer. Whereas in a digital multimeter, the range is adjusted automatically.
The fluke 101 multimeter the product is a 6000 count instrument. Digital multimeter working principle analyse a meter. In figure 25, the first difference you notice between the multimeter and the lvct is the. Multimeter uses and functions how to use a digital. At the very basic level you have the device itself, along with two probes, which are the black and red cables that have plugs on one end and metal tips on the other. Comparison of digital and analog meter can be damaged when dropped from bench level no usually damaged by rough treatment pointer attempts to deflect to. Switch on your multimeter, and set the dial to continuity mode indicated by an icon that looks like a sound wave.
Construction of microcontroller based digital voltmeter. Digital multimeter noncontact voltage tester to 600 v ac magnegrip holster with magnetic hanging strap 600 v acdc 10 amps acdc, fully safety fused resistance to 20 mw continuity beeper 1. All multimeters measure ac and dc voltage voltmeter, ac and dc current ammeter, and resistance ohmmeter. The available truevolt digital multimeter dmm models are. All the quantities are digitized using analog to digital converter and displayed in the digital form on the display. Multimeters can be used for testing batteries, household wiring, electric motors and power supplies. In this system, a typical multimeter may in this system, a typical multimeter may include features such as the ability to measure acdc voltage, dc current, resistance, temperature, diodes, frequency and connectivity. At first glance, a digital multimeter might look pretty confusing and maybe even a bit intimidating.
The most basic things we measure are voltage and current. Current, voltage, and resistance measurements are considered standard features for dmms. It is an ideal tool for labs, household and wireless enthusiasts. The product is battery powered with a digital display. The basics of digital multimeters the basics of digital multimeters by jim gregorec, ideal industries, inc.
How to use a digital multimeter measure voltagecurrent. By combining a versatile 8bit cpu with insystem programmable flash on a. Digital multimeter is a test equipment which offers several electronic measurement task in one tool. How to use a multimeter for starters, lets go over some of the different parts of a multimeter. The concept of the way the digital multimeter works is relatively straightforward, but it can be understood that measuring varying waveforms or intermittent voltages can give unusual results. This tutorial will show you how to use a digital multimeter dmm, an indispensable tool that you can use to diagnose circuits, learn about other peoples electronic designs, and even test a battery. A a digital ohmmeter which you can implement using the bs2 rctime command to measure resistance. For unattended monitoring of signals over time, to detect intermittent problems. Endowed with the key touching function instead of the traditional mechanical knobs, is a new type of 3 56 digital multimeter equipped with the lcd display device with the text height of 33mm which has the merits of visual display, easy operation, stable performance and high reliability. The digital multimeter principles resource guide provides the framework for handson activities and is a valuable instructional tool for training in group settings everything you need to teach the basics of digital m ultimeter. This dial has scales to indicate values for each of the tests the meter. The basics of digital multimeters ideal electrical. Design and construction of digital multimeter using pic.
Also it is important to select the right accuracy setting for the time that the measurement can be taken. Successful completion of tasks covered in the textbook can be documented by a certificate of completion included in the textbook. And for those of you who are more visual learners like me. Digital multimeter there are two main types of multimeters. You can determine this value by combining results from dc and ac measurements, as shown below. In an analog multimeter, the range has to be adjusted by the user. In this system, a typical multimeter may include features such as the ability to measure acdc voltage, dc current, resistance, temperature, diodes, frequency and. The meter is a handheld 312 digital multimeter for measuring dc and ac voltage, dc current, resistance, diode, transistor and continuity test with battery operated. High accuracy measurement, even with a low power factor. The multimeter is an electrical measuring instrument that combines the functions of an ammeter current measurement, a voltmeter voltage measurement, and an ohmmeter measurement of the value of resistance. Introduction the dvm810 is a compact multimeter with a 3 12 digit lcd for measuring dc and ac voltages, dc currents, resistance, diodes and transistors hfe. Safety information the fluke 101 complies with iec 610101 cat iii 600 v measurement category. This thesis describes the design and construction of digital multimeter using pic microcontroller. This instrument, kt117, is a digital multimeter which designed for making measurement of the lowvoltage equipment.
The megger has one current coil and the two voltage coils v 1 and v 2 the voltage coil v 1 is passed over the magnet connected to the generator. Skip to step 6 for an alternate way to perform a continuity test. Position the selector switch to the desired amp range and switch the meter on. It will measure up to volts dc and 750 volts ac in a cat ii environment and up to 600 volts ac and dc in a cat iii environment. In a digital multimeter the signal under test is converted to a voltage and an amplifier with an electronically controlled gain preconditions the signal. Features of digital multimeter digital multimeter is the most advanced instrument that makes use of modern integrated circuits for making electrical measurements. Digital multimeter working principle electrical a2z. Design and construction of digital multimeter using pic microcontroller khawn nue, dr. The construction of the megger is shown in the figure below. Digital multimeter principles is part of a comprehensive instructional package and is a must for all technicians, from contractors to maintenance staff. This animation simulates the action of various electrical quantities. Generally dual slope integration type adc is prefprred in the multimeters. View logged values graphically in the field right on the meter.
It can be used to measure dc voltage, ac voltage, dc. Some can also measure other electrical quantities such as frequency or even. Development of a digital multimeter international journal of. Laserliner multimeter xp operating instructions manual 88 pages brand. A digital multimeter or dmm is test equipment used for resistance, voltage, current measurement and other electrical parameters as per requirement and displaying the results in the mathematical digits form on an lcd or led readout. The lcd screen present on the upper portion of the multimeter basically displays four or more digits and also shows negative value if necessary. One of the first and oldest multimeters is theanalog meter, figure 2 and the other, now more widely used meter is the digital multimeter figure 1. When the pointer of the pmmc instrument deflects towards infinity, it means that the voltage coil remains in the weak magnetic field and thus. A digital multimeter dmm is an instrument that can measure several basic electrical quantities and shows the measurement with a number in a display. Connect the multimeter to the decade box and to one end of a battery. In this article we will learn how to use a digital multimeter and how this will help us in our journey with electronics, this will be a very basic article which will take your through the different operations of a multimeter will illustrative pictures and videos. Construction of a voltmeter and an ammeter from a galvanometer. Objectives at the end of this exercise you will become familiar with.
The current is converted to voltage by passing it through low shunt. Measurement and instrumentation construction of a digital voltmeter definitiona voltmeter is an instrument used for measuring electrical potential difference between two points of an electrical circuit. Measurement and instrumentation construction of a digital voltmeter definitiona voltmeter is an instrument used for measuring electrical potential difference between two. It is a type of multimeter which functions digitally. Tips on choosing and using a dmm, a musthave tool for almost all engineers. The digital multimeter is an instrument which is capable of measuring a. The first digit on many multimeters is only able to display a 1 so the ranges are limited to1 9. It is also known as the voltmeter or ohm meter or volt ohm meter. Digital multimeter principles instructors resource guide. It is an ideal instrument for hobbyists, for use in the field, for laboratories and workshops and for domestic applications. All configurations can be tested and any resulting connection errors are indicated.
There are pushbuttons on the meter to indicate which type of measurement is being made, and other pushbuttons to select the. The dm383b is a handheld, battery powered digital multimeter that is designed to meet iec 10101 en 610101, standards, the emc directive, and other safety standards see specifications. It is a handheld device with positive and negative indicator needle over a numeric lcd digital display. The following table summarizes the front panel keys and the menu structure. The multimeter displays 0 ohms with the leads shorted together. This meter is a handheld, battery operated digital multimeter dmm with multifunction. To better understand digital multimeters, its helpful to become clear on the basics of electricity. A same meter movement emmc is used to measure all the three quantities. Digital display digital multimeter dmm electronic volt ohm millimeter with digital display. The dm62 and dm66 digital multimeters combine a rich feature set, precise measurements, and quality construction into tools of exceptional. Introduction analog multimeter multimeter is a combination of a voltmeter, ohm meter and current meter.
Do not input a limit value over the range when measuring. Introduction whats included one autoranging digital multimeter one user manual one set of test leads one 9v battery. In this learning activity youll explore the functions and proper operation of a digital multimeter. An introduction to the digital multimeter by patrick hoppe. A warning identifies conditions and procedures that are dangerous to the user.