USE MULTIMETER MANUAL BEFORE YOU

You can also use it for checking continuity of wires and fuses. With this guide, youвЂ™ll learn the ins and outs of troubleshooting your home and household electronics using one of your toolkitвЂ™s handiest instrument.A digital multimeter or DMM is a useful test instrument for measuring voltage, current and resistance, and some meters have a facility for testing transistors and capacitors. Let us take a look at these common measurements using a digital multimeter.No more scratching your head at malfunctioning appliances. Resistance, voltage and current are the common measurements taken with the multimeter. How to Use a Multimeter Custom Search Having learnt the basics of analog and digital multimeters, you are now ready to make measurements.

Digital multimeters (DMM, DVOM), meanwhile, have a numeric display, and can also display a graphical bar indicating the measured value.Once reserved for engineers and electronic technicians, multimetersвЂ”sometimes called вЂњmultitestersвЂќвЂ”have come down in price and size, making them indispensable for homeowners who have basic knowledge of circuitry. Analog multimeters uses a microammeter with a moving pointer to show the readings. A typical multimeter can be used to measure voltage, current and resistance and even to check for conductivity.

Use Multimeter Manual Before You

Because multimeters vary from model to model, be sure to study your specific unitвЂ™s operating manual before you get started.Analog multimeters, or volt-ohm-milliammeters (VOM), have been around for decades and can still be found, affordably, at any do-it-yourself-type store. Learn the basics, however, and youвЂ™ll soon be able to perform a number of diagnostic tests on your own. Unlike a multimeter test, the curve tracer exercises the.If youвЂ™re new to multimeters, these gadgets may seem daunting at first. Set your meter to the diode test setting.

To avoid blowing a fuse, destroying the multimeter, or risking injury, do not attempt to test current higher than the maximum allowed for your unit.Among other things, multimeters can determine: While you can test household voltage with a multimeter, electrical-current-testing is limited to low-voltage circuits, such as small direct current (DC) motors or low-voltage alternating current (AC) appliancesвЂ”your thermostats and doorbells, for example. Applications and LimitationsBoth VOM and DMM models measure voltage, resistance, and current, replacing the need for individual voltmeters, ohmmeters, and ammeters.

Since polarity isnвЂ™t an issue in AC voltage, it doesnвЂ™t matter which probe you insert in either hole of a wall outlet insert both probes, and the multimeter will display the voltage at the outlet.Safety Tip: Hold probes by their insulated handles. If youвЂ™re testing a 12-volt car battery, select the next highest optionвЂ”20 DCV.Then make sure to connect your test leads to the proper jacks before testing: For voltage testing, plug the red lead in to the port labeled вЂњV.вЂќ For this and all multimeter tests, the black lead plugs into the common (COM) port.To test a batteryвЂ™s DC charge, touch the red probe to its positive terminal and the black probe to its negative terminal the multimeter will display the existing charge in the battery. For example, if youвЂ™re measuring the voltage in a 120-volt wall outlet, turn the multimeter knob to the next highest optionвЂ”200 ACV. Start by selecting the corresponding current on the multimeter and a voltage range higher than the current youвЂ™re testing. Conductive ability of an electrical pathwayWith a multimeter, you can measure both AC and DC voltageвЂ”particularly useful for locating short circuits or determining if a rechargeable battery is holding a charge.

The lower the reading, the less the resistance to electrical flow. When you touch the black and red probes to both ends of a component, simultaneously, youвЂ™ll get a reading. While you can test individual capacitors and components directly on a circuit board, youвЂ™ll get a more accurate reading if you remove a component and then test it. Plug the red lead into the port with the ohmвЂ™s symbol, вЂњО©,вЂќ and select the lowest ohmsвЂ™ function on the dial. If, for example, a microwave isnвЂ™t operating as it should, this checkup could help you you determine if you should replace a single non-functioning component on the circuit board or buy a new microwave outright.First, make sure the appliance is unplugged before testing. Multimeter in hand, you can test resistance in circuit board components and appliance elements throughout the house.

Measuring DC Voltage and ResistanceThe video below shows a multimeter being used to measure voltage from batteries (DC (direct current) voltage) and the resistance of some resistors.вЂ“> Measuring DC Voltage Selecting the DC Voltage RangeTo measure DC voltage using a multimeter, simply turn the selector dial on the multimeter to the DC voltage setting. A multimeter can be used to measure voltage, current, resistance, continuity and other parameters. If a multimeter bears the words, вЂњ10A MAX FUSED,вЂќ do not test any current you suspect might be higher than 10 Amps.A multimeter is a measuring instrument that anyone involved in electronics will need to use at some stage. Multimeters are вЂњfusedвЂќ at a maximum amount of voltage, which is typically lower than household current. When youвЂ™ve hooked up the circuit correctly, turn on the power source to measure the electrical flow rate, or amps, through the circuit.Safety Tip: As previously mentioned, do not test a circuit that exceeds your multimeterвЂ™s capability. Finally, the neutral power-supply lead (usually white) connects to negative appliance wire (also white).

Getting the leads the right way around (correct polarity вЂ“ red on positive and black on negative) does matter on the old analog multimeters (the type with the indicator needle). Black on positive and red on negative) then a digital multimeter will show a negative sign next to the voltage reading on the display.On a digital multimeter, it does not matter if the leads are reversed when measuring voltage. PolarityIf the red and black multimeter probes are connected the wrong way around to the battery (i.e. This connection may have other symbols marking it as well, such as the ohm symbol (О©).After applying the probes to the battery, the voltage of the battery will be shown on the multimeter display.

Using certain multimeter models, you can test to be sure that components вЂ” such as diodes, capacitors, and transistors вЂ” function properly. This can be seen by the measurements taken in the video.A multimeter is an electronics testing device that, um, tests multiple things, including resistance, voltage, and current. A single 1.2V cell is measured last.When 1.2V batteries are fully charged, they will have a voltage of slightly more than 1.2V. The second battery measured contains two cells or 1.2V Г— 2 = 2.4V. The first one measured has six cells, so the voltage should be about 1.2V Г— 6 = 7.2V. Measurement ResultsIn the video, batteries made up of 1.2V rechargeable cells are used.

You will use a multimeter all the time. Find a model whose price you like and then splurge on the next higher-priced model. You can find them for about if you want fancy features, you can spend over $100.

How a multimeter worksA multimeter has a set of leads: a black one and a red one.

How To Use Multimeter