how to calculate esc for brushless motor

How to Calculate ESC for Brushless Motor? [Know It All]


The ESC (electronic speed controller) is essential to the proper operation of electric RC cars. Your electric motor’s speed and braking force are controlled by the ESC. 

Without it, you can not properly operate your RC vehicle.’

When it comes to selecting the right one, one needs to learn to calculate it first.

So, how to calculate ESC for brushless motor?

First, we must discover the motor’s voltage rating. Then we need to get an ESC that can handle the current. It can be rated like a 6S motor with a 50 amp maximum. For this, the ESC must be rated at least 6S for this motor. Surpassing the ampere rating is wise. We prefer to give ESC headroom.

That was only a glimpse of information. To operate it properly you will need further information. This article will provide all the information you need.

Hope you will stick around.

Process of Matching a Brushless Motor with ESC

Matching a brushless motor with the ESC is not that tough. For this, we will just need to identify the voltage rating of the motor we are using. After that, we will need to buy an ESC that can handle the sufficient current that we are planning to run.

Just to understand, a motor can be rated as 6S and 50 amps maximum. In this case, we will need a 6S battery to operate. To use a 6S battery we will need an ESC that has a rating of at least 6S. 

It allows the engine to operate itself at full load. Using the ampere rating above required is wise. We prefer to give the ESC a little headroom. If the required amp rating is 20 ampere then a 30 amp rated ESC is perfect for this.

It will boost the maximum performance, efficiency, and safety. It also keeps the motor comparatively cooler.

Connecting a brushless motor with ESC is not that complicated. It takes only a few steps to complete.

How to Calculate ESC For Brushless Motor?

To calculate the ESC for brushless motors the amperage rating should always be checked. This is the most simple and only way. But it depends on a few other factors to decide or calculate the perfect ESC for the brushless motor.

Calculating ESC for RC Aircraft

For RC aircraft propeller load should also be taken into consideration. Folding propellers, fixed propellers, and variable pitch propellers always get an ESC. This ESC is rated as the same voltage as the motor.

But a higher amperage rating of up to 20% is recommended. In this fact, we need to pay close attention to weight. The reason behind choosing a higher amperage is the ESC will run cooler.

Even though its FET layout isn’t being pushed to its limits, motors can occasionally spike. The ESC’s higher amperage rating will serve as an overhead. When it comes to radio-controlled helicopters, the same rules apply as above. 

Calculating ESC for RC Car

The ESC used in the RC car must match the voltage that is required for the motor. It’s recommended to go over at least 30% in matching motor amperes. Spike ampere rating should be carefully looked at.

We might see peak figures as high as 1080A on ESCs rated at 80A is considered normal. Never use a sensored motor in conjunction with a nonsensical ESC, and vice versa. With sensored motors, it is not as easy as volts and amps are with conventional motors.

Are you employing more than four servos? You can either purchase an ESC that has a 10A BEC or disable the built-in BEC on the ESC. This is done by cutting the positive wire but leaving the signal and ground wires connected. And use a standalone external BEC.

Choosing ESC on Brushless Motor

Choosing the right ESC depends on the consumption of the motor. It is determined by how many amps a motor draws to operate. If our motor draws 20 amps then we should go with an ESC capable of handling 20 amps or more.

For maximum safety, performance and efficiency we need to choose an ESC that has at least 10 amps more capacity than the motor.

There are many brands available for ESC which makes it harder to choose. Here we recommend some best brushless motors and ESC combo.

Product 1
Product 2

Can We Connect Brushless Motor with Battery Without ESC?

The simple answer is “NO”.

A Brushless DC (or 3-phase) motor cannot be driven directly from DC.

A rotating magnetic field is required to generate torque and rotation. This can be accomplished through the use of an alternating current source,

 a commutator, or an electronic speed controller (ESC) to regularly swap the coils. The electronic commutator has been repurposed as the ESC.

Can We Control a Brushless Motor without an ESC?

A brushless motor is a type of AC motor. In every 180 degrees of rotation, a mechanical commutator switches the direction of the current flowing through the windings.

To reverse the current in a Brushless motor, an electrical device is used externally to the motor. The controller has to know what angle the motor is at, thus there is a sensor that tells the electronics that information. 

To provide power and feedback, the BL motor requires a greater number of connections. However, the complexity of the electronic controller is more than that of a standard DC motor, but the motor itself is extremely simple.

All of this is controlled by the ESC. As a replacement for the DC motor’s internal mechanical commutator, it should be regarded as an essential part of the overall motor. Of course, you have the option of creating your controller, but the result will be the same.

If you still haven’t understood yet, learning how brushless motors and ESC work might help.

That’s all we had to say. Hope it was useful to you.


Can you run 3S on a 60A ESC?

When the weight and motor kV issues are taken into consideration, a good 60A ESC will perform admirably on three-cell batteries.

Does ESC choice affect motor power?

The ESC has a minimal impact on power consumption or performance. An ESC with a greater amp rating will be less stressed and run cooler. It’s always a good idea to have your ESC running at a maximum of 80% of its maximum power.

Is a higher amp ESC better?

An ESC with higher output power typically has better internals than an ESC with lower output power. The higher the amperage rating, the more aggressive the motor can be.


In any case, thank you for sticking with us. In this article, we tried to explain how to calculate ESC for brushless motors? Hope you found the answer you were looking for.If not please contact an RC expert. It might help.

Good Luck!

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