A multimeter is a versatile tool that can be used to measure a variety of electrical quantities. When working with electronic circuits and devices, measuring electric current in milliamps (mA) is common. But what does a 50-mA read mean on a multimeter?
This article explains what it signifies and how to measure it using both analog and digital multimeters.
Basics of Multimeter
Before we delve into the specifics of 50 milliamps, let’s take a moment to understand the basics. A multimeter, also known as a multimeter or VOM (Volt-Ohm-Milliammeter), is an electronic measuring instrument. It combines several functions in one unit, typically measuring voltage (volts), current (amps), and resistance (ohms).
To measure current, the multimeter uses two main techniques: series and parallel. In this context, we are interested in measuring current in series, where the multimeter becomes a part of the circuit through which the current flows.
How to Measure Milliamps with a Multimeter
A multimeter can precisely measure milliamps when set up properly. Here are the steps:
1. Select Milliamp Mode: Turn the knob or push the buttons to choose a milliamp range on the multimeter. Common ranges are 50 mA, 200 mA, 500 mA, etc. Select a range above the expected current.
2. Connect Test Leads Correctly: Insert the black lead into the COM jack and the red lead into the mA jack on the multimeter. This enables milliamp measurement.
3. Break the Circuit to Insert the Multimeter: Power off the circuit. Disconnect a wire to break the flow of current.
4. Touch Probes to Circuit: Attach the black and red probes across the separated points of the circuit to measure the milliamps flowing through that part of the circuit.
5. Power on and Note Reading: Turn on the circuit and check the milliamp reading on the multimeter display.
What Does 50 mA Look Like on an Analog Multimeter?
When measuring 50 mA on an analog multimeter, set the device to an appropriate milliampere range, such as 0-100 mA, and connect it in series with the circuit. The analog display will showcase the current flow by positioning the needle on the scale, and if the current is indeed 50 mA, the needle will point accurately to the corresponding mark.
Analog multimeters typically feature a linear scale, facilitating straightforward interpretation of readings. Keep in mind that while analog meters provide useful measurements, their precision may be slightly less than digital counterparts, so selecting the right range is crucial for accuracy in current measurements.
What Does 50 mA Look Like on a Digital Multimeter?
On a digital multimeter, a current of 50 milliamps will display a numeric value of “0.05” (or very close to it) on the screen. This is because a digital multimeter displays the measurement based on the selected mode. So, in milliamp mode, it shows the current in amps (A).
To convert it to milliamps, you simply move the decimal point three places to the right.
So, a reading of 0.05 A indicates 0.05 amps, which equals 50 milliamps (0.05 A = 50 mA).
Multimeter Resolution and Accuracy
The resolution and accuracy of the measurement depend on the quality of the multimeter and range selected. A less expensive multimeter may show “0.053” or “0.048” for a 50-mA current. More expensive models will be accurate to within 0.001 A in the 200-mA range.
Always try to select a range setting just above the measured current for optimal resolution and accuracy.
Effects of Incorrect Range Setting on Multimeter
Using the incorrect current range on the multimeter can impact the reading:
- If set too high, the resolution may suffer. A 50-mA current on the 10A range may show “0.00”
- If the range is too low, it will overload. A 50-mA current on the 20-mA range will likely show “OL”
Select a setting just above the measured current for optimal results.
How to Troubleshoot Inaccurate Milliamp Readings
If the milliamp readings seem inconsistent or inaccurate, try these steps:
- Inspect test leads for damage, corrosion, or loose plugs
- Check battery – replace if low
- Verify multimeter calibration and accuracy
- Test known current sources for comparison
- Use proper jack ports for mA measurement
- Eliminate external interference such as noise or EMI
This will help isolate any issues with the setup and ensure accurate 50 mA readings.
Safety Tips When Measuring Milliamp Current
Follow these tips to safely measure the Current of a Circuit:
- For safety, keep these guidelines in mind when making milliamp measurements:
- Turn off power to the circuit when possible
- Double-check connections before turning on
- Do not touch exposed conductors or probe tips
- Avoid shorting connections or probes
- Use caution when working with sensitive electronics
- Wear eye protection
- Make sure your body is insulated from current pathways
Frequently Asked Questions (FAQs)
1. Is 50-mA Dangerous?
Answer: Any amount of current can be dangerous. Always follow safety precautions when measuring live circuits.
2. What Setting on a Multimeter Do You Use to Test Milliamps?
Answer: To test milliamps, set your multimeter to either DC or AC mode, and adjust the dial to the “mA” or “m” position within the ampere section marked with an “A.” Ensure you select a milliamp range greater than the expected current to avoid overloading the multimeter.
3. What is the Symbol for Milliamps on a Multimeter?
Answer: The symbol for milliamps on a multimeter is “mA” or “m”.
With the correct setup and technique, a multimeter can precisely measure small currents down to the milliamp level for troubleshooting and testing electronic circuits and components. Ensuring you follow the proper steps outlined in this article will allow you to confidently and safely take milliamp measurements.
- Basics of Multimeter
- How to Measure Milliamps with a Multimeter
- What Does 50 mA Look Like on an Analog Multimeter?
- What Does 50 mA Look Like on a Digital Multimeter?
- Multimeter Resolution and Accuracy
- Effects of Incorrect Range Setting on Multimeter
- How to Troubleshoot Inaccurate Milliamp Readings
- Safety Tips When Measuring Milliamp Current
- Frequently Asked Questions (FAQs)
- To conclude
Subscribe to our newsletter
& plug into
the world of circuits