Have you ever encountered electrical supply failure at your home or any of your electric appliances gone out of power suddenly? Or you are an electronics enthusiast and want to know how to use a multimeter? If you want to diagnose and sort out minor faults at your home or office then this guide is really made for you. With little general knowledge, you can check the outlet’s voltage, any appliance’s amperes and resistance as well.
This blog can also help you if you are a working electrician and keen on electrical knowledge. Multimeters are the most helpful tool in the electrical and electronics fields. Along with voltage, current, and resistance we can also use them to check diodes, continuity, capacitance, frequency, and some more advanced parameters.
First of all, we strongly recommend that if you don’t have electrical background you should first get proper safety training before using multimeters. As you know it’s a dangerous work of playing with live wires having high and low voltage in them. Without safety measures, there would be more chances of getting shocked accidentally. Don’t worry you don’t have to be an engineer to do some basic tasks.
Before doing any task with multimeter you should first consider safety and take necessary measures. Make sure that you are not barefooted, without insulation gloves, and children are away from you if you are at home. Read multimeter’s manual carefully and try to act upon it completely. This will ensure your and your meter’s safety.
How to Measure Voltage?
Voltage test is the most common test people do through multimeters. Voltage is actually a potential difference between any two points of conductor from which electric charge or current is flowing. There are mainly two types of voltage, one is called low voltage and the other is high voltage. In low voltage, we generally have 120v and 220v systems in different countries, in three phase 440v systems. High voltages are specific to grids and powerhouses only.
- First of all turn on your multimeter, put test leads to related sockets. COM or common is a black color test lead that is used only for common or neutral.
- Digital multimeters have separate sockets, one is for voltage and resistance, other is for checking current. So for testing voltage put red lead into voltage socket.
- Now is the time to set the right switching option. On dial of multimeter, switch rotary selector to voltage. If your multimeter has a manual range then set range according to voltage level, for example, if you are testing volts under 200 set range under 200 volts.
- In auto range multimeters there’s no need to set range, meter will automatically detect that.
- Now is the time to select points where you will connect multimeter’s probes and get voltage readings. Always select intact and easily accessible connection points, so you can get best accurate readings.
- Be clear about which is a neutral point and which is phase in case you are working on single phase system. In three phase you can connect probes to any of two phases, in order to get phase to phase readings.
- Carefully connect black lead to neutral or common, red to live phase and watch results on multimeter lcd.
- Double check the results for more satisfaction.
Check current through multimeters?
If you have a clamp multimeter then your life is easy, as it’s a best device to check amperes. You only need to encircle live wire through the clamp jaw, and you’ll get readings without even making physical contact. Clamp meters work on faraday’s law of mutual induction and are so amazing handy devices.
The procedure of testing current through digital multimeter is given below,
- To measure current through DMM you have to break circuit first, don’t forget to turn off power before breaking circuit.
- Set meter’s range to maximum amps which is generally 10A and 20A max in some digital multimeters.
- Take a look on sockets, to ensure that test leads are at right position.
- Now connect test leads to broken wires, it can be done more perfectly by alligator clips otherwise you can also do it by probes.
- Check readings on multimeter lcd.
Measuring Resistance through Multimeter?
Resistance is another common test performed by multimeters. Resistance is actually the overall opposition of the conductor against flowing charge. Specially ground resistance should be regularly checked to make sure circuit’s safety. The process of testing resistance by multimeter is not much different from voltage and current. Below are some points about the procedure of ohm measurements in multimeters.
- First of all check test leads should be at resistance checking socket, generally with this sign Ω .
- Now turn off circuit where you want to measure resistance. Without disconnecting circuit you can’t measure it.
- Now adjust ohmic range from rotary dial switch. Set resistance range more than the magnitude you are going to test for more good sensitivity. For example if you want to measure 1 ohm resistance, set range to 20 ohms.
- Now connect test probes to circuit or element under test and check readings.
Continuity Test With Multimeter
Continuity as its name suggests is a general test that tells whether the circuit is complete and ready for current flow. It’s just like when an airplane has to be landed at the airport, teams monitor if the runway is clear, and everything is fine. Then they allow airplanes to land on the runway. A continuity test is a simple test, assisted by a beep buzz sound that indicates the condition of the circuit.
It’s a very beneficial test that allows us to know component’s health. We can test various equipment like switches, circuit breakers, fuse, wires, motors, and almost all other electric circuits and components.
- Firstly, check dial position it should be on continuity or ohm setting.
- Now turn off circuit or device which is under test, also don’t forget to separate it from other components in circuit.
- Some multimeters have a dedicated continuity test button, so press that button.
- Now connect test probes to starting and ending points of the circuit or device.
- If multimeter beeps buzz sound, it means circuit path is complete, otherwise, multimeter will not beep.
Testing Battery Voltage
Dc power means batteries are the only source of power at farthest locations. We also see batteries around us everywhere, according to a survey there,s no room no office left in the modern world where you can’t find a battery of any type.
To check overall battery health and charge voltage is a primary factor. If you have a little know how to multimeter functionalities you can easily check your battery voltage. Otherwise follow steps described below,
- First of all insert COM or black probe into COM socket and red probe into socket with V or mv option.
- Set meter dial to dc voltage point.
- In manual range multimeters, you also have to set the range. Suppose you want to test battery of 12v then set range at minimum of 20v dc.
- Now connect black probe to negative sign on battery and red to positive and check reading on screen.
Leo Maxwell is basically an Electrical engineer and hobby tech writer, having 13 years of experience in the electronics and instrumentation industry. He has hands on experience working in various fields like Powerhouses, solar, automotive, and FMCG.
During his career, he has used many power tools and meters in electrical projects. Now his aim is to explain tools and troubleshooting in easy guides to help people. Other then it, leo loves traveling, reading books and DIY tasks.