Laura Wilcox, Peter Carroll
Engineering, Electronic Technology, Maritime Science
Material Type:
Activity/Lab, Assessment
Community College / Lower Division, College / Upper Division, Career / Technical
  • Inclusive Pedagogy
  • Mass CC Engineering
  • inclusive-pedagogy
  • License:
    Creative Commons Attribution

    Digital Multimeter Training

    Digital Multimeter Training


    This resource provides is a multimeter tutorial as well as an assignment for students to create a video showing that they understand how to use a multimeter.  Its purpose is to get beginning engineering students, with varying levels of experience with a multimeter, to learn and master a multimeter's features and functions.

    Inclusivity Statement

    This exercise is designed to bring all students to the same level of proficiency with a
    digital multimeter. The assignment requires students to learn how to safely use and maintain a
    multi-meter and then take the next step of understanding and teach what they learned in the
    form of a self-made video. Student’s knowledge of mutli-meter use varies tremendously when
    first entering their first basic electrical lab. The best video’s will be kept as an Open Educational
    Resource for the lab for future reference. This will enable students who have no experience
    with mutli-meters and students that may just need a refresher to quickly come up to the same
    level of proficiency without taking up lab time.


    Target Audience- Engineering students who are enrolled in Electrical Machines Lecture and Lab
    and have already completed Physics 2 and understand basic electrical concepts including
    voltage, current, frequency, resistance, and capacitance.

    Purpose- The purpose of this document is to provide a reference for students in the use of
    digital multimeters. This guide will provide students with important safety considerations, an
    overview of the functions of digital multimeters, and guidance on how to measure various
    parameters within an electrical circuit or electrical devices. At the end of this training document
    is a sample assessment that asks the student to demonstrate various features of the digital
    multimeter as a way to measure the student’s learning. Included is a rubric for grading the

    Learning Objectives- At the completion of this training, the student will be able to identify the
    components of a digital multimeter, describe the major functions of a digital multimeter, and
    demonstrate a safety inspection, and demonstrate the correct method for measuring AC
    voltage, DC voltage, resistance, and continuity.

    Lesson 1: Parts of a Multimeter

    Figure 1. A common multimeter

    ● Battery location
    ● Fuse location

    ● Backlight
    ● Digit indication
    ● Selector dial
    ● Push buttons
    ● Function modifications

    ● Different attachment tips
    ● Importance of insulation and rubber grips

    Lesson 2: Safety Inspections

    When choosing a meter:

    ● Make sure the meter you use meets the safety standards for the environment in which you’ll be working.

    ● Only use meters that have recessed input jacks

    ● Choose a meter that has overload protection on the ohms function. This protects the meter, the circuit, and the user from harm.

    ● Choose a meter with fused current inputs (and check the fuses before making current measurements).

    ● Choose a meter that is suitable for the voltages or currents that you wish to measure. For example, if you plan to measure 480 Volts AC, your meter should be rated for CAT III 600 V. You can research the International Electrotechnical Commission (IEC) category and voltage ratings to learn more about classifying power distribution categories.

    ● Choose a meter that has been independently tested that it meets the IEC standards. A UL, CE, CSA, RCM, or other testing lab stamp is a good way to know that the meter you’re using has been verified to meet the standards and is safe to use.

    Before getting started:

    ● Battery Health- It’s important to take the batteries completely out of the multimeter if you don’t plan on using it for greater than six weeks, otherwise, the batteries may corrode to the point of not being able to function. Many multimeters will indicate on the display if the battery is weak and needs replacing. This indication will look like a battery symbol (see Figure 2 below). The meter may also display “batt'' when you turn it on if the battery needs to be replaced.

    Figure 2. Battery needs replacement in display

    You may also check the ‘health’ of any battery using a multi-meter

    ● Inspect the physical condition of the leads. No breaks in insulation or wires! Only use leads that have shrouded connectors and finger guards

    ● Check continuity between leads upon startup: Continuity check with multi-meter

    ● Check the physical condition of the meter. The body of the meter should not be cracked or broken. The battery door should be secure. The selector switch should operate freely and have detents at each position to prevent the knob from inadvertently being moved while using the meter.

    ● Power the meter on and check that the display is in good condition.

    Prior to starting work with the meter:

    ● Try not to work alone, especially with high energy circuits. Make sure someone
    else is monitoring you and knows where and when you’re working with electrical

    ● Follow all equipment safety instructions.

    ● Be aware of high current and high voltage equipment and circuits and use
    appropriate equipment, such as special high current amp clamps and high
    voltage probes

    ● Know the voltage or current range that you plan to measure and use the
    appropriate range on the meter. If you’re unsure, select the highest range and
    dial it down as you need to get a good measurement.

    ● Always connect the hot (red) test lead last and disconnect it first.

    ● Always disconnect the power on a circuit before connecting leads when you want
    to measure resistance and current.

    ● Always double check that you’re using the correct function on the meter for what
    you want to measure


    Lesson 3: Functions and Uses

    Common functions found on the digital multimeter are AC Voltage, DC Voltage,
    Continuity, Resistance, and Amperage. Other functions may also be available on some
    multimeters, such as diode test mode, but won’t be discussed in this document.

    AC voltage measurement is indicated by the symbol V with a sine wave over the top of
    the V. AC voltage is the type of voltage that is supplied by power utilities or created by
    generators. The wall outlets in homes and businesses are typically supplied with 120V AC at
    60 Hz (in the US). AC voltage is given on a digital multimeter as the RMS or root-mean-square
    of the voltage waveform. RMS is the DC equivalent of an AC voltage. Most digital multimeters
    will read “true RMS”, which means that the meter is capable of giving RMS measurements for
    waveforms that are not sinusoidal and may be square, sawtooth, or ripple waveforms. Meters
    that are only “average responding” cannot give accurate readings for non-sinusoidal waveforms
    and shouldn’t be used when the power supply is not a standard sine wave.

    DC voltage measurement is indicated by the symbol V with a straight line over the top of
    the V. DC voltage is that which is supplied by batteries, either large industrial batteries or
    smaller consumer type batteries like those found in cars, clocks, and electronic equipment.
    Some electronics that are plugged into 120V AC wall outlets contain rectifiers that convert AC
    voltages into DC voltages to power the electronic device. It’s important to recognize those
    devices to ensure that you’re using the correct function on the multimeter to measure circuit

    Continuity is a simple function that determines if a circuit is open or closed. The
    continuity symbol on the multimeter looks like a speaker. The speaker symbol is used because
    when the meter is selected to the continuity function, a closed circuit will be indicated by a high
    pitched beeeeeep from the meter. This noise is often accompanied with an ohm measurement
    on the display screen. An open circuit will produce no noise and is often accompanied by a
    display of “OL”. “OL” indicates an overload condition, such as infinite resistance. The continuity
    function is useful for quickly determining if a wire or circuit is physically broken. It is also a good
    function to quickly check the integrity of your multimeter leads when first powering on the

    Resistance is a function to measure the ohms of resistance within a circuit or across an
    electronic device. Because resistance measurements can vary widely, it’s important to select
    the correct range if your multimeter is not an auto-ranging type. It is also VERY important to
    remember to power down the circuit before measuring resistance. If power is left on, the circuit
    or the meter could be damaged. The digital multimeter will display the quantity followed by
    either the Ohm symbol, kilo-ohms or mega-ohms. If you’re concerned with getting very accurate
    measurements when reading resistance, you should start by measuring the resistance of the
    test leads themselves, then subtracting the resistance of the leads from the final resistance
    measurement. Resistance measurements that exceed the meter’s capacity are displayed as
    “OL” (overload). An open circuit is effectively infinite in resistance and therefore will show on the
    display as “OL”.

    Current measurements taken with the digital multimeter are unique in that the multimeter
    must be used so that all of the circuit current will flow through the multimeter, not in parallel with
    it. There are two ways to do this- one is by using a clamp-on meter and the other is by shutting
    off the power to the circuit, opening the circuit and using the meter leads to complete the circuit
    again, and then powering the circuit back up to read the amps of current flowing through. Prior
    to connecting the test leads to the circuit, the hot lead must be removed from the meter
    connection used for Volts and Ohms and reconnected to the connection jack labeled for Amps.
    Lesson 4- Procedures for Using Digital Multimeter Functions

    NOTE: Prior to taking measurements of live circuits, be sure to go through the safety
    checklists above. Always double check yourself and work slowly and methodically to prevent
    harm to yourself, the multimeter, and the circuits.

    Measuring voltage:

    1. Turn the selector knob to VDC or VAC as appropriate for the circuit being tested.
    2. If the digital multimeter has different ranges, select the correct range. If you’re unsure, select the highest range to begin. You can always select a smaller range if it’s not correct.
    3. Plug the black lead into the COM input connection.
    4. Plug the red lead into the V / Ohm input connection.
    5. Touch the probe tips across the power source or load to be measured. When measuring DC voltages, be sure that the black lead is touching the negative or ground side of the circuit and the red probe is touching the positive side.
    6. View the reading, noting the unit of measurement.

    Figure 3. Multimeter set up properly to read DC Voltage.

    Figure 4. Multimeter measuring the DC voltage of a battery. Selector is set to “V” with flat line over it as opposed to a sine wave over the “V”.

    Figure 5. Multimeter properly set up to measure AC voltage in milli-volts

    Measuring Continuity:

    1. Turn the selector knob to continuity test (the speaker symbol).
    2. Plug the black lead into the COM input connection.
    3. Plug the red lead into the V / Ohm input connection.
    4. Touch the probe tips to either side of the wire or component to be tested.
    5. Listen for the beep from the meter to indicate a closed circuit. If no beep, the circuit is open. Recheck your lead placement to verify.

    Figure 6.  Multimeter doing a continuity test on a fuse.

    Measuring Resistance:

    1. Turn off power to the circuit.
    2. Turn the selector knob to Ohms.
    3. Plug the black lead into the COM input connection.
    4. Plug the red lead into the V / Ohm input connection.
    5. Touch the probe tips on either side of the component or circuit you want to measure.
    6. View the reading, noting the unit of measurement.

    Figure 7. Multimeter selector dial set to ohms to measure own resistance.

    Figure 8. : Multimeter selector dial on“speaker” and ohms to set up and check a circuit for continuity.

    Measuring Amperage:

    1. Turn off power to the circuit.
    2. Make an opening in the circuit for the meter probes by disconnecting an electrical connection, cutting a wire, or unsoldering a connection.
    3. Turn the selector knob to A (AC) or A (DC) as appropriate.
    4. Plug the black test lead into the COM input connection.
    5. Plug the red test lead into the Amp or Milliamp input connection.
    6. Connect the test probes to the circuit across the break in the circuit so that the multimeter completes the circuit and all current flows through the meter.
    7. Turn the circuit power on.
    8. View the reading, noting the unit of measurement.

    Figure 9.  Multimeter selector dial setup to measure micro-amps.


    Figure 10. Multimeter selector dial setup to display milli-amps.


    Assessment of Learning

    Methods of assessment:

    1) In order to familiarize students with the multimeter, they will be asked to create a training
    video. The video shall be between 4 and 5 minutes and shall have the following topics

    a) Briefly describe the physical buttons, leads, selector dial and analog display

    b) In detail, describe each of the options on the selector dial and what application they might be used for.

    c) In detail, describe and show an example of using the analog display by measuring voltage, amperage or resistance. This should include exactly how to read the display, which colored lines to use and what scale the lines represent.

    d) In detail, from start to finish, video how to properly and safely take a voltage measurement using a multimeter. The video should show an actual measurement being done with voice-over describing the steps.

    e) Finish the video by ending with multimeter safety as well as proper battery storage.

    Assignment: Make a short (5-10 minute) training video demonstrating the proper operation of
    a Digital Multimeter, and submit it to Blackboard by the deadline.


    • Capabilities of the meter.
    • Safety precautions for using the meter.
    • Meter display when a measurement is out-of-range.

    Demonstrate and explain the use of the meter for these common tasks:

    • Verify that an outlet is live
    • Determine if a battery is charged.
    • Measure a resistance. Choose something in approximately in this range 5 Ω < R < 100 KΩ
    • Perform a continuity test.
      • Switches and fuses are good objects to test.
      • If your meter doesn't have a dedicated continuity setting, explain how to use the available functions to determine continuity.

    Satisfactory completion of this assignment satisfies STCW Assessment OICEW-7-1E.


    • Plan in advance what you are going to say and do.
    •  Get someone to hold the camera for you.
    •  Large videos take a long time to upload to Blackboard. Record at SD or HD, not 4K resolution and at 24 or 30 frames per second

    Rubric for Grading

    1. Does the video meet the time requirements
    2. Video description for physical attributes includes all XX options on the multimeter
    3. Video description of how to read the analog display includes discussion of the various units on the display and how to read the units with the pointer indicator
    4. Video demonstration shows the student(s) know how to safely use and read a multimeter and is expressed in a step-by-step, understandable approach such that students new to a multi-meter could effectively learn how to use it after watching the video.
    5. Video covers safety check for continuity of leads and proper battery use and storage
    6. Communication (voice-overs) in video match what is being presented in the video
    7. Voice-overs are understandable and have a proper pace
    8. Video demonstrates checking live outlet
    9. Video describes capabilities of the meter
    10. Video describes safety precautions
    11. Video demonstrates if a battery is charged
    12. Video demonstrates measuring a resistance between 5 ohms and 100 kilo-ohms
    13. Assignment will be re-done if students make a safety error in any category