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# Measuring Temperature With Multimeter

## Using a Multimeter: Chapter 8

Content

In this module, you will learn how to use a multimeter to measure temperature. Let's jump right in!

### Figure the Settings Out

Not all multimeters can measure temperature. Before you begin, check 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 COM port. The positive prong on the thermocouple will be plugged into the 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. Based on the resistance of the thermistor, the multimeter can read the temperature.

## How to measure temperature using a multimeter?

Letās go through the process of measuring temperature.

1. Start by confirming that the negative end of your thermocouple is plugged into the COM port.

2. The positive end of the thermocouple should be plugged into the temperature port.

3. Rotate your dial until it points towards the temperature symbol. You may need to use the function key to access the temperature measurement.

4. When your meter is set to a temperature, you will see an āFā or āCā on the screen. These stand for Fahrenheit and Celsius.

Recall that there are two units for measuring temperature:

• Celsius, and

• Fahrenheit

You will need to set your multimeter to measure the correct units.

To switch your multimeter between Fahrenheit and Celsius, you will need to use the range button. While your dial is set to a temperature, press the range button to change units. The unit will be on the display. For example, the units on the display with switch from āFā to āCā when you press the range button.

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. That is the temperature of the object.

## 3. Conclusion

Itās a wrap! Wasnāt that hard, was it?

Learning how to set your meter to measure temperature in the right way is very important in order to get an accurate measure. In this section, you learned how to use your multimeter to measure temperature. In the next section, we will cover multimeter safety.

What did you think of this lesson? Let us know in the comments below and help us make it better for you. Please do share it with everyone else who you think may need it!

## Test Yourself!

Question #1: A thermistor is a resistor whose resistance value changes depending on the temperature.

1. True

2. False

True, the thermistors resistance changes as it heats up or cools down.

Question #2: You use standard red and black multimeter leads to measure temperature.

1. True

2. False

False, you will use a thermocouple and a thermistor to measure temperature with your multimeter.

Question #3: All multimeters can measure temperature.

1. False

2. True

False, not all multimeters can handle temperature. Check if your meter can measure temperature before plugging in any thermocouples.

Question #4: To access secondary measurements, like temperature, you may need to use what button:

1. Function

2. Hold

3. Range

4. Min/Max

The function button allows you to access secondary measurements. What you are measuring will always be shown on the multimeters display.

Question #5: To change units from celsius to fahrenheit, you may need to press which button?

1. Function

2. Hold

3. Range

4. Min/Max

The range button is used on some meters to change the units for temperature.

Question #6: Before you touch anything with the thermistor, the meter should be displaying the:

1. Units

2. Air temperature

3. Type of measurement

4. All of the above

Before touching anything with the thermistor, your meter should displaying the units, air temperature, and that you are measuring temperature.

Question #7: When you touch the thermistor to an object, the meter will instantly display the objects temperature.

1. True

2. False