QTV #6 - Analog vs Digital Multimeters

Summary

In this video, Martin Lorton compares analog and digital multimeters, specifically the Fluke 87 Series 5 and the Mastec M7040. He discusses the pros and cons of both types, including the durability of digital meters versus the sensitivity of analog ones, ease of reading digital displays, and the accuracy of analog needle movements in fluctuating signals. Lorton also highlights challenges such as range selection and parallax error in analog meters. He concludes by acknowledging the growing functionalities of digital meters, while still recognizing the value of analog meters in specific situations.

Takeaways

• 🔍 The video compares the Fluke 87 series 5 digital multimeter with the Mastec M7040 analog multimeter.
• 💾 Digital multimeters are more robust and can withstand shocks and drops better than analog ones.
• 📈 Digital meters provide quick and accurate readings with their bar graph feature, unlike some slow and jumpy bar graphs on other digital meters.
• 📋 Analog meters are sensitive to vibration and harsh shocks, which can damage the needle or even the unit itself.
• 📝 When taking a reading, digital meters offer a clear digital display, while analog meters require selecting the correct range and dealing with parallax error.
• 🔍 Analog meters can be advantageous in quickly identifying changes in signal or sensor readings due to their needle movement.
• 🔢 Digital meters offer higher resolution and accuracy with readings down to several decimal places.
• 🔩 Analog meters require calibration each time a resistance reading is taken, which can be a hassle.
• 📊 For fluctuating signals, analog meters can provide a clearer picture of the signal's range and variability compared to digital meters.
• 🛠️ Modern digital meters offer additional functionalities such as min-max averaging, data logging, and auto hold, which analog meters lack.

Q & A

What is the main focus of the video?

The video focuses on comparing the pros and cons of analog versus digital multimeters, specifically comparing the Fluke 87 series 5 and the Mastec M7040.

Why was the Fluke multimeter chosen for comparison?

The Fluke multimeter was chosen because it has a fast update speed on the digital display and a good bar graph, which makes it a fair comparison to an analog meter.

What is one advantage of digital multimeters over analog ones mentioned in the video?

Digital multimeters are more robust and can withstand shocks and drops without going out of calibration or damaging the needle, unlike analog meters.

How does the video demonstrate the challenge of reading an analog multimeter?

The video shows the process of selecting the correct range and then deciphering the needle's position on the scale to get an accurate reading from an analog multimeter.

What is 'error of parallax' mentioned in the video?

The 'error of parallax' is a challenge when reading an analog meter, where the needle appears offset from the scale due to viewing angle, potentially leading to inaccurate readings.

How does the video highlight the difference in resolution between analog and digital multimeters?

The video points out that while analog meters can theoretically offer high resolution, it's often difficult to read fine graduations, whereas digital multimeters provide readings to several decimal places with ease.

In what scenario does the video suggest an analog meter might have an advantage over a digital one?

The video suggests that an analog meter might have an advantage when quickly checking multiple test points for the same reading, as the position of the needle can be easier to note than changing digits on a digital display.

How does the video demonstrate the challenge of reading fluctuating signals on a digital multimeter?

The video shows a scenario where a fluctuating signal is difficult to interpret on a digital multimeter due to the need for the digits to settle and the auto-range function causing the display to jump around.

What is the process of measuring resistance with an analog multimeter as shown in the video?

The process involves setting the appropriate range, zeroing the display by touching the leads together, and then taking the measurement, which will show the resistance value on the scale.

Why is it necessary to calibrate an analog multimeter each time you change the range?

Calibration is necessary because the battery driving the measurement and several ranges use the same scale, and each range may require a different calibration to ensure accurate readings.

What additional functionalities do digital multimeters offer that are not mentioned in the script?

Digital multimeters offer functionalities such as min-max averaging, data logging, and auto hold facilities, which are not typically found in analog multimeters.