A multimeter is a compulsory tool for dealing with electric faults and electronic or automation circuit troubleshooting. Electricians and engineers are already aware of multimeter symbols like resistance or others but newbies or students may get confused by dozens of symbols and buttons, need some help for it. In this guide, we’ll teach you about dmm symbols and buttons in an easy way so in future you can differentiate them and be able to operate multimeters wisely.
What are Multimeter symbols?
Multimeter Symbols are signs given on meter body across selector wheel and on buttons to indicate a function or features. For example, for ac voltage, there is a symbol VAC that indicates this button or jack is dedicated for ac voltage testing. By learning them one can easily master multimeter operations.
Ac voltage
Ac voltage is the most common voltage source present at homes and industries connected by local grids. For this VAC symbols are used. There are different magnitudes of ac voltage in the world from 100v to 220vac. Ac voltage is denoted by V with a wavy line upon it. See below,
Ac and dc signal symbols
DC voltage
Dc voltage or VDC is known for small power electronic devices like batteries, sensors, and automotive equipment. Dc stands for direct current.
Current
As we know that current is the rate of flow of charge, by this we calculate how much power a device or machine would need to run. Current is symbolized by “A” on multimeter with the same pattern of wavy and straight lines of ac and dc on them.
Millivolts
It’s a minor subdivision of voltage to calculate minor voltage presence. Usually, electricians need them for some sensors, plc , automotion, and automotive works. Millivolts are denoted by (m V) on multimeters.
Milli and microamps
Same as millivolts milliampere is a subdivision of current unit ampere, I milliamps is equal to 1/1000 amps. It’s denoted by m A , another subdivision of it is microamp μA which is the least known current a multimeter can detect.
Resistance
Resistance, as its name suggests is a natural opposition of current within a metal or element. We calculate resistance in units of ohms symbolized by Ω , which are further divided into kilo ohms kΩ and mega ohms MΩ when values are higher in number. 1 kilo ohm is equal to 1000 ohms while 1 megaohm defines a value of one million ohms.
Frequency
Frequency tells us the number of cycles of current flow per second through a circuit. Its unit is hertz, so a 1 hertz means the flow of 1 cycle per second. Hertz is denoted by Hz on multimeter. 50 hz and 60 hz are the two most popular frequency systems in world.
Capacitance
Capacitors are the most common electric items we can find in fans, motors, and many other devices. They store electrical charge, their capacity to store electrical energy is calculated by capacitance. For capacitance calculation system international unit is farad and its symbol on multimeter is “–|(– “ , it has further subdivisional units of micro and nanofarads.
Continuity check
A continuity test is a general test performed by electricians to verify whether a circuit loop is intact or broken from somewhere. For this multimeters has an audio beeper indication which tells that the circuit loop is fine. This function is denoted by a sound type signal on multimeter. Continuity can also be checked through resistance testing method.
Diode test
This test is not available in all multimeters but a best electronics multimeter will definitely have this function. A diode test actually measures voltage difference across two points of diode.
Error symbol
It’s a symbol to indicate some problem like overload or shorts within the multimeter or circuit you’re working on. If ever your multimeter shows this error or caution sign on meter screen you should abruptly disconnect the multimeter from circuit and see manual or consult with an expert electrician.
Multimeter buttons
ON/OFF for switching multimeter on and off, however many multimeters has this control on selector switch rather then with button.
Min/Max button is for recording signal fluctuations, give indication when a value cross previously recorded reading. It stores lowest, highest and medium values.
Hold button is for freezing multimeter screen at any time to record results.
Yellow or function button is to activate secondary function of a dial setting like capacitance or temperature.
Rel button which is symbolized with a delta sign is for recording a relative value for future use and reset display to zero value.
Range button is usually present in multimeters with auto ranging ability. By pressing this button for two seconds meter will start working on auto ranging, if you want to use multimeter on manual ranging press it again and again for required function.
A button with brightness or light sign is for illuminating multimeter’s display with backlight.
Final words
like every language we spoke on earth has its own symbols and writing styles, similarly, electrical functions and readings are denoted by some dedicated symbols which you can see on a multimeter interface. At start, everyone can get confused with them, but with time they will not be a difficult task for you.
We tried our best to guide you about multimeter symbols and buttons and recommend you to learn them before going into field for doing work with your multimeters.
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.
