In this multimeter use guide, learn how to measure temperature using a multimeter with thermocouple and thermistor instead of test leads.
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Multimeter Basics
There are two types of multimeters: digital multimeters and clamp multimeters. Most of what is pictured in this guide is a digital multimeter.
Multimeters can be used to measure various measurements:
Measure voltage in Volts
Measure current in Amperes
Measure resistance in Ohms
Measure continuity in Ohms
Measure capacitance in Farads
Measure temperature in Farenheit or Celcius - this is the focus of this guide!
Multimeters have 2-4 ports for test leads or probes to be plugged into. Probes are used more for the other electrical measurements.
Probes have one end of the wire called the plug end that plugs into the multimeter port. The other end of the wire called the probe end is used to touch the component of measurement.
Remember that black probe represents the negative probe, and red probe represents the positive probe.
Ensure that the probe ends of your probes do not touch as you measure using the meter, as that can short the circuit and become a safety hazard.
Tools To Measure Temperature

You may associate measuring temperature to using a thermometer when you're sick with a fever. You may also be thinking about a temperature probe, which you use for food. For electrical components within circuits, tools like digital multimeters and temperature sensors are used instead of a thermometer or temperature probe.
Setting Up Your Multimeter To Measure Temperature
Not all digital multimeters can measure temperature. Before you begin, check to see if your multimeter can measure temperature. If your meter can measure temperature, you will see a thermometer symbol on the multimeter dial.
To measure temperature with your multimeter, you are not going to use the standard black and red leads. Instead, you are going to use a thermocouple and a thermistor.

A thermocouple is a rectangular block with two metal prongs. One prong will have a positive (+) symbol. The other a negative (-) symbol. The thermocouple has a sheathed wire extending from it. We use this wire to measure temperature.
The negative prong on the thermocouple will be plugged into the meter's COM port. The positive prong on the thermocouple will be plugged into the meter's temperature port. The symbol for the temperature port is a thermometer. It is usually the same port used for voltage.
The thermocouple has a wire extending out of it with a thermistor at the end of the wire. A thermistor is a resistor whose resistance is dependent on temperature measurement. Based on the resistance of the thermistor, the multimeter can read the temperature.
Process of Measuring Temperature
Making Sure Your Multimeter Is Set Up:
Confirm that the negative end of your thermocouple is plugged into the COM port of your digital multimeter.
The positive end of the thermocouple should be plugged into the temperature port of your digital multimeter.
Rotate your dial until it points towards the temperature symbol. You may need to use the function key to access the temperature measurement.
When your meter is set to a temperature, you will see an “F” or “C” on the screen. These stand for Fahrenheit and Celsius.
Measuring Temperature
The two units for measuring temperature are Celsius and Fahrenheit. Be sure to set your multimeter to measure the correct units for your circuit. To switch your multimeter between the two units, use the range button. The unit will be on the display.
Once you have confirmed that your meter is on the correct setting, hold the wire extending out of the thermocouple. At the end of this wire is a thermistor that the meter will use to measure temperature. Right now, the meter should be displaying the air temperature.
To measure the temperature of an object, press the tip of the thermistor onto the object. The meters display will slowly begin to change as the resistor heats up or cools down. Wait for the temperature to be a constant number. The temperature of the object should appear on the display.
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FAQs
How can I measure temperature with a multimeter?
To measure temperature with a multimeter, you need to ensure your multimeter has a temperature setting. If it does, you will use a thermocouple, which is connected to the multimeter in place of the regular test leads. The thermocouple’s prongs should be plugged into the correct temperature ports on your multimeter, and you must set the multimeter to the temperature symbol on the dial.
What is a thermocouple and how does it help measure temperature?
A thermocouple is a small device consisting of two metal prongs with different electrical properties. One prong is marked as positive, and the other as negative. It is used with a multimeter to measure temperature by converting thermal energy into a measurable electrical signal. The thermistor at the end of the thermocouple wire detects temperature changes by altering its resistance, which the multimeter interprets as a temperature reading.
Can all multimeters measure temperature?
Not all multimeters are capable of measuring temperature. To determine if your multimeter can measure temperature, check for a thermometer symbol on the multimeter’s dial or refer to the user manual. If your multimeter has this feature, you will be able to use it to measure temperature.
How do I switch between Celsius and Fahrenheit on my multimeter?
To switch between Celsius and Fahrenheit on your multimeter, use the range button to toggle between the two units. You should see the unit of measurement displayed on the multimeter screen once the setting has been changed. Make sure to set the correct unit based on the temperature you are measuring.
What should I do after setting up the thermocouple and multimeter?
Once your thermocouple is correctly connected and your multimeter is set to the temperature symbol, you can begin measuring. Hold the thermistor wire and touch its tip to the object whose temperature you wish to measure. The temperature reading will change as the thermistor responds to the object’s heat, and you should wait until the reading stabilizes for an accurate result.
Is it necessary to use a temperature sensor or probe for measuring temperature with a multimeter?
Yes, a temperature sensor like a thermocouple is required to measure temperature with a multimeter. Unlike a standard temperature probe used for food or a traditional thermometer, the thermocouple is specifically designed to work with a multimeter to provide precise temperature readings for electrical components.
How do I know if my multimeter is set to the correct temperature range?
After connecting the thermocouple to your multimeter, confirm that the display shows either "F" for Fahrenheit or "C" for Celsius. If your multimeter has a range button, use it to switch between Fahrenheit and Celsius, ensuring it matches the desired unit for your temperature measurement.
What is the purpose of the thermistor in temperature measurement with a multimeter?
A thermistor is a resistor that changes its resistance based on the temperature. When connected to the multimeter, it allows the device to measure temperature accurately. The multimeter uses the thermistor’s resistance value to calculate and display the temperature reading.
Can I use a regular probe or test lead to measure temperature?
No, regular test leads are not suitable for measuring temperature. Instead, you must use a thermocouple or temperature sensor designed for this purpose. These devices convert temperature changes into electrical signals that your multimeter can read and display.
What types of multimeters can measure temperature?
Only certain digital multimeters have the capability to measure temperature. Typically, these multimeters feature a dedicated temperature port and a thermometer symbol on the dial. Popular models, such as the Fluke 87V, are equipped with temperature measurement functionality.
Can I use the temperature measurement function while the circuit is live?
It is important to be cautious when measuring temperature in a live circuit. For safety, always make sure to use insulated tools, and ideally, measure temperature on non-live components. If possible, it is safer to turn off the power before taking a temperature measurement, particularly when using the thermocouple on electrical components.
What is the role of the temperature port on a multimeter?
The temperature port on a multimeter is specifically designed for connecting a thermocouple or temperature sensor. This port allows the multimeter to read the electrical signals from the thermocouple, which it then translates into a temperature measurement, either in Celsius or Fahrenheit.
Why do I need to wait for the reading to stabilize?
The temperature reading on the multimeter might fluctuate initially as the thermocouple adjusts to the temperature of the object being measured. To ensure an accurate reading, it is important to wait until the temperature measurement stabilizes on the display.
What is the maximum temperature that can be measured with a multimeter?
The maximum temperature a multimeter can measure depends on the specific model and the thermocouple being used. Always refer to the multimeter’s manual for its temperature range, as exceeding this range could damage the multimeter or the thermocouple.
Are there any safety precautions I should take when measuring temperature with a multimeter?
Yes, safety is crucial when using a multimeter to measure temperature. Always wear insulated gloves and safety glasses when handling electrical equipment. If measuring temperature in a live circuit, make sure to use insulated thermocouples and avoid contact with any exposed wires or components.
Quiz
Question #1: Which is a resistor whose resistance value changes depending on the temperature?
Thermometer
Thermistors
Thermocouple
Temperature probe
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Question #2: True or False - You use standard multimeter probes to measure temperature.
True
False
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Question #3: True or False - All multimeters can measure temperature.
True
False
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Question #4: To access secondary measurements, like temperature, you may need to use what button:
Function
Hold
Range
Min/Max
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Question #5: To change temperature units from Celsius to Fahrenheit on your multimeter, which button do you press?
Function
Hold
Range
Min/Max
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Question #6: Before you touch anything with the thermistor, the meter should be displaying the:
Units
Air temperature
Type of measurement
All of the above
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Question #7: True or False - When you touch the thermistor to an object, the meter will instantly display the objects temperature.
True
False
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