How To Test Brushless Motor With Multimeter?

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Are there some issues with your motor? Wondering how to test brushless motor with multimeter?

Using a multimeter, test the brushless motor. First, connect your multimeter to the brushless motor. Set the multimeter to DC since brushless motors are DC. The multimeter must be connected to the motor. Then, with the help of probes, measure the voltage, resistance, and amperage.

Well, if you got a minute then read away and learn about the prospects and things. We will show you how to use a multimeter for testing a brushless motor.

Utilization of a Multimeter for a Brushless Motor

Simply use a multimeter to take the readings. Then check if our brushless motor is operating properly.

Before doing anything, you should set the multimeter into DC mode. It is due to the fact that brushless motors are DC motors. Afterward, connect the common probe. It is also known as Com probe as the word com is replaced by com sometimes.

After that, take the black-colored jack. You will have to adjust the red probe according to the reading.

You may test the resistance, amperage, or voltage of your RC motor with a multimeter. Also, you can check your ESC using a multimeter and find out the details here.

Compare your reading to the optimal reading statistics and identify the problems for yourself.

4 Steps To Test Brushless Motor Using Multimeter

You need to frequently test the brushless motor and monitor its performance. Test your brushless motor using a multimeter and carefully follow the instructions.

It is critical that you test, check, and run your brushless motor on a regular basis. Take the motor and use a multimeter for testing it based on the instructions:

Step 1: Testing The Resistance Value

Unplug all of the drive’s power and amplifier connections. We ought to keep the motor’s cord linked to it.

Set your multimeter to Ohms and link the wires testing probes to the relevant jacks. The black one represents Com, whereas the red one represents Ohms. Using this information, we can connect the wires. Then we should set the needle on the multimeter to zero.

Now, obtain a reading on the three wires using the probes. Then we mark the wires namely A, B, and C accordingly. Simply said we will now test these in the following order: AB, BC, and CA.

The measurements should be infinite, indicating that there is no issue with the motor. So to say if the reading comes to 0 every time. Afterward, something in the motor is not correct.

Remember to keep your multimeter’s leads isolated at all times. These so-called multimeter leads should not come in contact with other cables. Otherwise, there will be dysfunction.

Step 2: Locating Open And Shorted Winding Issues

Our brushless motor windings might have an issue. They might be open or shorted. If the motor winding is broken or removed, it shows an opening. However, a shorted coil indicates insulation failure

A multimeter can be used to diagnose these problems.

Examine the A and B connection, B and C connection, and C and A connection. These connections on the cables will show an average resistance between 0.3 to 0.8 ohms.

There is a break between the phases if the reading is zero. A value of 2000 ohms or infinity indicates an open winding.

If the reading is zero, there must then be a gap between the stages. Well interesting fact that a value of 2000 ohms or infinity indicates an open winding.

Step 3:  (The Insulation System)

To determine if the motor is grounded or not a megohm measurement is performed. It may also determine whether the brushless motor’s insulating scheme is adequate.

Simply move the multimeter’s red probe to the Megaohm jack this time.

You must provide your engine with 1000 rpm of incoming power. Connect the motor to a high-quality larger brushless motor to get the desired value.

Follow the same process to check the wires after you have turned on the motor. The reading will be in the 600 to 2000 Megohm range and the length of the shorts must be less than 20 Megohms.

As a general rule, if the measurement is less than 600 Megaohms, it may indicate damage to the circuit.

Step 4: The Amperage

By measuring the amperage, you can measure the current flow in your brushless motor. Current sensing is essential for a brushless motor to perform with stability. 

Insert your multimeter’s red probe into the “amp’ Jack first. Connect the motor circuit to the multimeter line. Connect the power cord to the probe.

The amperage should be zero. If the reading fluctuates, it indicates a serious problem with your brushless motor.

Check the brushless motor for malfunctions. You can identify the issues happening frequently and avoid internal malfunctions.

You have finally completed the testing of your brushless motor and can see how a multimeter can be handy at times.

What Can a Brushless Motor’s Multimeter Reading Tell Us?

A multimeter can tell you whether or not your motor is operating properly. You might need expert assistance to repair your brushless motor.

On the contrary, a multimeter assists in determining the problem location and fixation.

A multimeter measurement can reveal various brushless motor issues. This covers concerns with motor windings, power supplies, insulation, and so on. The measurements indicate motor health.

However, you may get the combo of ESC and brushless motor that is the best for you.

Also, I would like to recommend to you some multimeters that can be useful to you.

Name Details
Product 1 
Product 2 

Hope you like these recommendations. Because I think these will definitely pique your interest.


How long will a brushless motor Last?

If you want a motor that will endure a long time, choose a brushless motor. Brushed motor life is restricted by the kind of brush. It can range from 1,000 to 3,000 hours on average. However, brushless motors can range from tens to thousands of hours on average. It happens due to the lack of brushes.

Why are brushless motors wired with three wires?

The three wires boost the brushless motors’ pulling power. Understanding this aids comprehension of stepper motors further down. The brushed dc motor’s two wires may be thought of as forward and backward. Brushless wires are represented by the numbers 1, 2, and 3.

Is it possible to use a brushless motor without an ESC?

No, it is not possible. A brushless direct current motor and a three-phase alternating current induction motor are somewhat similar. To produce the spinning field, you must utilize a brushless DC motor controller (ESC).

Concluding Words

Hope you get the clue about how to test brushless motor with multimeter. We have discussed in detail 4 easy steps for easily testing your brushless motor.

If you have any questions, please leave them in the comment section below.

We will meet again next time! Good day!

About the author

Travis Murray

I am Travis Murray, and my love for RC began in 2017. It gradually turned into a passion, leading me to become an RC enthusiast and blogger. I write in-depth reviews and DIY guides for RC enthusiasts to provide troubleshooting tips and insider knowledge to help starters find the hidden gems in the hobby.
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