Differences Between A Brushed And A Brushless RC Motor

what is the difference between a brushed and brushless rc motor

Remote-controlled cars are one of the best recreational toys available in the market, and if you get one, you are assured a great deal of fun. When you purchase an RC car, you will notice that some are with brushless motors, and others have brushed motors. If you are new to the RC world, you would not understand the differences. Continue reading to find out.

The major difference between brushed and brushless motors is the mode of generating electricity. Brushed motors have brushes and a commutator that produces electricity. The commutator rubs against the brushes. Brushless motors have magnets, an external rotor, and 3 phase driving coils.

It is very easy to differentiate between brushed and brushless motors if you see one. Nevertheless, the way they generate electricity is not the only difference between them. We will examine more differences.

Brushed RC Motor

Brushed motors are old technology; the first use of these motors was in 1836. There are fixed magnets and an electromagnet that rotates in a brushed motor. This type of motor is called a brushed motor because of the brushes it has inside it. The brushes are usually made of graphite, silver, or copper and generate and convert electricity to motion.

There is a mechanical rotary switch in this motor that delivers the current, and it is the commutator. When the commutator rubs against the brushes, a magnetic field is created, repelled, and attracted. This causes the rotor to rotate (a process referred to as armature). At this point, the motor has caused the RC car to move. The windings of a brushed motor are located on the rotor and the magnet on the stator.

brushless motor

As the rotor rotates, the polarity changes, and when a half-turn is completed, the polarity is changed, and the rotor still spins. The brushes transfer power from the battery to the rotors; one brush transfers negative polarity and the other positive polarity. Once a half-turn is completed, there is a switch in contact with the negative and positive brushes.

When the polarity switches, the negative end of the rotor becomes positive, and the positive end becomes negative. The motor spins every time there is a change in polarity.

Pros of Brushed Motors

The assumption that since brushless motors are an improvement to brushed motors, the latter has no advantages is false. You will enjoy some benefits if you use a brushed motor in your RC car. Brushless motors are very cheap; if you have a damaged motor and need one, you can purchase a brushed motor.

Brushed motors are designed to be perfect for entry-level RC cars and new users. They provide a two-wire control, so you have enough power for tactical and tight driving with a simple command. RC cars with brushed motors can more easily maneuver through terrains than cars with brushless motors because they have fewer external components.

Brushed motors can also be configured, so you can modify and adjust them till you get the exact speed you desire and the voltage you will use. This option is not available on brushless motors.

Brushed motors are water-resistant to a point, and if a brushed motor gets wet, you can open it up and leave it to dry. This is because all the parts are manufactured from either carbon or metal. As long as the motor is dried, it will still function effectively.

Cons Of Brushed Motors

Brushed motors are not very efficient; they have an efficiency level between 75 percent and 80 percent. The brushes are a mechanical limitation, so the motor can only offer a low-speed range for RC cars. The brushes and commutators of a brushed motor are susceptible to wear and tear.

So, brushed motors require constant replacement and repairs; this will require money. The irony of it, brushed motors are inexpensive to purchase but are expensive to maintain. Since the wear and tear of the brushes make it require regular maintenance, these motors have a shorter lifespan.

There is a lot of electromagnetic and electrical noise produced in brushed motors. The noise is a result of the endless switch of the brushes, commutators, and shafts. Since brushed motors require contact with these elements to work, the rotational force is reduced, and heat loss increases.

Brushless Motors

Brushless motor is a newer technology, and the first brushless motor was manufactured in the 1970s. These motors are a great improvement to brushed motors; instead of brushes and commutators, there are rotating magnets, fixed coils, and a small computer chip, the electronic controller that changes the polarity of the coils as the motor spins.

The magnets of a brushless motor are located on the rotor, and the windings are on the stator instead of the rotor. With this new design, there is no need for brushes, so the motor functions more efficiently. There is also an amplifier in a brushless motor activated by the computer chip to create a magnetic field in the motor. Electronic commutation is produced based on the sensor position instead of the mechanical rotary switch in a brushless motor.

Pros Of Brushless Motors

Brushless motors are more efficient than brushed motors; they have an efficiency level between 85 percent and 90 percent. Brushless motors have a longer lifespan, and sometimes, they last longer than the other parts of an RC car. The lack of brushes and commutators accounts for a longer lifespan. These motors do not require regular maintenance and replacements like the brushed motors.

Brushless motors are easier and cheaper to maintain; the only part of a brushless motor that requires periodic maintenance is the bearing; all it needs is lubrication. Lubricating the bearing is not difficult, nor does it require a high level of skill like replacing the brushes of a brushed motor.

Brushless motors are small and lightweight; this is the major reason they make an RC car very fast. They do not add extra weight to the vehicle, so it has better speed and improved handling capabilities.

brush motors

Brushless motors do not wear out; no commutators and brushes are rubbing against each other to produce electricity. So, there is no friction, and the parts do not wear out. These motors produce less heating, making them have better performance and no electrical limitation.

With a brushless motor, your RC car has more power and longer runtime than a brushed motor. There is no mechanical limitation on a brushless motor. They also deliver high torque and produce less electrical noise. Brushless motors are durable and reliable, and you can trust them to always function effectively.

Cons Of Brushless Motors

Brushless motors are more expensive than brushed motors. The complex electronics and high cost of production make these motors expensive to purchase. They may be expensive, but you will enjoy the value of the money spent.

Brushless motors do not offer good speed control. Unlike a brushed motor that you can configure to get a desired speed and voltage, you cannot do that on a brushless motor. This downside makes it unsuitable for beginners because control of the car becomes difficult, especially on rough terrains.

Brushless motors require an electronic speed controller (ESC) to function well. So, every time you purchase a brushless motor, you must also get an ESC that is compatible with it. Brushless motors have a circuit board that must not come in contact with water; otherwise, it is permanently damaged.

Final Thoughts

If you are a beginner, you should use an RC car with a brushed motor; you have better control of the car. However, if you are a professional, a brushless motor is what you require. Brushless motor provides more speed, efficiency, longer lifespan, low cost of maintenance, while brushed motors provide better speed control, water-resistance, less complexity, and less price.

By Shawn Manaher

Shawn Manaher loves to play with new toys and dive into new hobbies. As a serial entrepreneur, work definitely comes first but there is always room for hobbies.