How to Read Analog Multimeter Readings (4-Step Guide)

You may ask why you need to know how to use an A/D multimeter in this digital age.

In the field of electronics testing, analog multimeters are a reliable tool. Experts still use analog meters for troubleshooting in some areas due to their accuracy and true conversion of RMS values.

I'll cover more below.

How to read an analog scale

The analog scale consists of many lines and numbers. This can be confusing for beginners, so here you will learn the basic techniques for reading the scale correctly:

1. You can use the ohmic scale (the top line is Ω) to calculate resistance from left to right. You must multiply the scale measurement by the range selected based on the specified range. If your range is 1 kΩ and the pointer is steady at 5, your reading will be 5 kΩ.
2. You must perform span adjustment in the same way for all quantity measurements.
3. You can measure voltage range and current on a scale below the ohmic scale. DC voltage and current are measured next to the ohmic scale on the black line. The red line always represents AC measurements. It is important to remember that you must evaluate current and voltage data from right to left.

To read the analog meter reading, follow these steps:

Step 1: Connect an analog multimeter to the test leads. Use the following configurations to measure various quantities:

Use cases:

• Measuring voltageNote: To measure voltage, you must set the meter to the ACV (AC voltage) or DCV (DC voltage) range, depending on the type of voltage being measured.
• Measuring currentNote: To measure current, you must set the meter to the ACA (AC) or DCA (Direct Current) range, depending on the current being measured.
• Resistance measurement: You would set the meter to the ohm (ohm) range.
• Continuity testing: To test for continuity, you must set the meter to the continuity test range, often indicated by a symbol such as a diode or speaker.
• Checking transistorsNote: You must set the meter to the hFE (transistor gain) range to test the transistors.
• Checking CapacitorsA: To test capacitors, you must set the meter to the capacitance range (uF).
• Diode testNote: To test diodes, you must set the meter to the diode test range, often indicated by a symbol such as a diode or delta.

Step 2: Attach test probes to the object to be measured in each configuration and check the scale readings. We will use DC voltage monitoring as an example in this discussion.

Step 3: Insert test leads into two ends of an AA battery (about 9V). Depending on the selected range, the pointer should fluctuate on a scale. The arrow should be between 8 and 10 on the scale if your battery is fully charged. 

Step 4: Use the same method to measure quantities in different configurations.

As previously stated, range selection and multiplication are necessary for accurate analog readings. (1)

For example, if you are measuring the voltage of a car battery with an A/D multimeter, the range should be larger. You will need to do a simple multiplication to read the final output.

If your DC voltage range is 250V and the needle is between 50 and 100, the voltage will be around 75 volts depending on the exact location.

Introduction to the panel

Understanding the device's panel is also critical to reading an analog multimeter. This is what you need to know:

• Volt (B): unit of electrical potential difference or electromotive force. It measures voltage, the difference in electrical potential between two points in a circuit.
• Amplifiers (A): Unit of electric current. It is used to measure the flow of electrical charge in a circuit.
• Om (Ohm): A unit of electrical resistance. It is used to measure the resistance of an element or circuit component.
• small currents (µA): A unit of electrical current equal to one millionth of an ampere. It measures very small currents, such as in a transistor or other small electronic component.
• kilo (kΩ): ​​A unit of electrical resistance equal to 1,000 Ω. It measures relatively high levels of resistance, for example in a resistor or other passive circuit element.
• megomms (mΩ): A unit of electrical resistance equal to 1 million ohms. It measures very high levels of resistance, such as in an insulation test or other specialized measurement.
• ACV stands for AC voltage and DCV stands for DC voltage.
• Interleaving (AC) is an electric current that periodically changes direction. This is the type of current that is commonly used in domestic and industrial power systems and has a frequency of 50 or 60 Hz (hertz) in most parts of the world.
• Direct current (DC) is an electric current that flows in only one direction. It is often used in electronic circuits and devices such as batteries and solar panels.
• ACV и DCV measurements measure the potential difference between two points in a circuit. AC voltage measurements are used to measure AC voltage and DC voltage measurements are used to measure DC voltage.

An analog multimeter may also have other readings or scales on the dial or scale, depending on the meter's specific features and capabilities. It is important to refer to the manual or instructions for the specific multimeter being used to understand the meaning of these values.

In the lower left corner of the multimeter, you should see where to attach the probes.

You can then access more options through the ports in the bottom right corner. When you need to invert the polarity of a measurement, an optional polarity switch comes in handy. You can use the central switch to select the measured value and desired range.

For example, turn it to the left if you want to measure the voltage range (AC) with an analog multimeter.

Important tips and tricks

• When using analog multimeters, select an appropriate range for reliable results. You must do this both before and during the quantity measurement. (2)
• Always calibrate your analog multimeter before doing any serious testing or troubleshooting. I highly recommend weekly calibration if you use your device on a daily basis.
• If you find significant changes in measurements, it's time to replace the batteries.
• If you are sure of the exact value of the measured value in volts, always select the highest range.

Recommendations

(1) multiplication - https://www.britannica.com/science/multiplication

(2) measurement of quantity - https://www.sciencedirect.com/science/article/

pii/026322419600022X