An analog multimeter is an essential tool for any electrician. This post will cover how to use the most basic functions of a multimeter and some other tips and tricks that you might not know about.
As an electrician, the ability to use a multimeter is paramount. A multimeter measures voltage, current, and resistance. It can be used to determine which wires are live or not by testing them for voltage.
The first step in using a multimeter is understanding its features. The meter will have two probes with crocodile clips at one end and an LCD on the other that displays information about what it measures through different lines of text like “VOLTS” or “OHMS.”
Analogue Test Meter
The old-fashioned analog multimeters had a needle that would move based on the input measurement, and these meters were often used in laboratories. The needles are now replaced with digital displays to make it easier for people who aren’t so great at science to know what’s happening.
Analog meters are used in many laboratory photographs before the 1970s and 1990s when digital technology replaced analog techniques.
The basic meter of these instruments is a moving coil meter that deflects from its rest position as the measurement quantity increases; this allows for an easy view to determine what measurements need to be made by simply looking at it rather than having to have extra devices like clocks or rulers on hand while doing readings.
The analog test meter is an excellent device for testing different types of resistors. The range on the analog device can be adjusted by adding or removing series and parallel resistors to get it just right; this makes it simple enough even if you’re not an electrical engineering expert!
There are sometimes several different connections used for the probes. There are usually common and standard measurement probe connections. Still, there’s also a labeling system with this instrument to indicate which range it is calibrated in Volts for voltage measurements or Amps for current readings. If you’re using something like 10Amp reading, then that connection will be labeled appropriately.
Electricity is hard to visualize, so I’ve always thought of it like a river. There’s the volume and force (similar in electrical amperage or amps) flowing together until they encounter an obstruction such as rocks that change its flow pattern (resistance measured in ohms). Hold this big picture about both electricity and VOMs:
- Alternating current (AC) voltage: The type of electricity that powers your house.
- Direct current (DC) voltage: The type found in auto and household batteries.
- Resistance (measured in ohms): The lower the reading, the more manageable your electrical current flows through.
- An open circuit equals trouble: There is high resistance from a faulty connection, broken part, or switch that’s been turned off. No current will flow without the complete circuit path and heated wire to make contact with.
- A closed-circuit is good: It means a minimum of resistance is present because the device is working. Note: Check for any loose wiring in the circuit paths you are testing to ensure that there are no broken connections (“short circuits). Short circuits can harm, destroy equipment and start fires.
- Continuity testing is an everyday use for multimeters and allows you to see if an open, shorted, or closed circuit exists in your appliance.
- On a VOM, infinity signifies an open circuit. It shows up as an unwavering needle on an analog multimeter that won’t move off the display’s far left side. Digital multimeters will read “0.”
- A zero means that the circuit is closed, and this can be seen on a VOM by looking at an analog scale if it moves to one side or displays zeros as digital numbers.
- Selecting the proper range is very important and refers to setting your multimeter’s function switch on a higher-than-expected voltage or amperage value. Digital meters have an ingenious feature, auto-ranging, that automatically selects you once you set it to measure resistance (ohms), current (AC/DC), or volts. Auto-ranging gives you the safest testing capacity every time you change back and forth between measuring ohms from voltage readings.
Understanding the Analog Multimeter Scale
The workings of an analog meter scale must be fully clear to us before we can jump into the steps.
This is important because, after all, it has been so acclimatized that reading the analog scale with our digital tools could become slightly confusing.
Understanding the Panel
Analog multimeters are often used to measure voltage, which is of particular interest in the electrical field.
You can switch polarity depending on whether or not you want positive (or relative) readings and negative (or absolute) ones. This gives engineers a lot of flexibility when they’re measuring AC voltages, for instance!
The Analog Scale
The ohmic scale is used to measure resistance. The range you select will affect the reading of the pointer on this line. For example, if your meter says 5k and you have a range selected from 1-1000 kΩ (the black line), then that means your readings are at 5000 Ω.
The voltage measurements can be read in different ranges displayed by lines below it indicating DC or AC depending on which red box has been chosen for measurement.
The chief difference between an analog multimeter and voltmeter/ammeter is the scale. A voltmeter will only have two scales for AC and DC voltage measurement, whereas an ammeter or a galvanometer will only have one scale for AC and DC amps measurement.
Using Analog Multimeter
If you have an analog meter, please follow the following steps.
- Connect the test leads to your analog multimeter
- Use the following setups for measuring different quantities:
- Use an AA battery to measure voltage, DC voltage, and current.
- Use an AC socket to measure AV voltage and current.
- Use a resistor to measure resistance.
- Use a wire to measure continuity.
- For each test, connect the probes to the object you are testing. In particular, when doing this for DC voltage, make sure your reading is correct on a digital voltmeter- or DVM, as it’s more commonly known.
- Connect the probes to either end of an AA battery. Depending on the range you have selected, the pointer should move across a scale from 8-10 volts when fully charged and 3-5V in other ranges. If not done yet, please choose DC voltages higher than 10 V for your multimeter’s voltage setting (usually 12 V or 10 V).
- As a starting point, try the same technique for other setups to measure the respective quantities.
The range of your analog multimeter matters when you measure something with high voltage. For example, when testing a car battery, use the higher ranges to get an accurate reading and do simple multiplication to find out how much energy is left in it!
The analog multimeter is an essential device for measuring voltage, current, and resistance. It functions the same as a Digital Multimeter (DMM), but you need to put more effort into this instrument because many different parts can be used depending on what measurement needs to be done. We hope this guide has been helpful!