Electric and mechanical parts make up your RC car. However, they are not indestructible.
If you own an RC vehicle, you need to understand that the parts inside of it cannot last a lifetime, especially the motors. No matter how much you try to maintain them, they will eventually burn out for various reasons. Your RC’s brushless motor may burn out if the amperage becomes too high. But that’s not the only reason why they burn out.
Can you burn out brushless motors?
Brushless motors, like every other electric component run hot naturally, but they should run hot up to a certain degree.
In this article, we help you understand what causes your brushless motor to burn out and how to avoid it.
Why do brushless motors burn out?
Brushless motors are sensitive and will burn out quite easily. In fact, there are 5 most common reasons your brushless motor will burn out include:
- Running too hot
Your brushless motor is heat sensitive. When the temperature exceeds its limit, the biggest risk you run is damage to the rotor’s magnet. In essence, when it overheats, it causes the permanent magnets on the motors to weaken, which will also cause the motor to fail. To avoid burning out the motor, you need to avoid raising the motor’s temperature past 170°F (76°C).
- To many amps
How much current flows through the motor also pose damage to your brushless motor. When you run on too many amps, you risk increasing the motor’s temperature, making it overheat, possibly melt plastic parts, warp metal parts, and maybe even start a fire. In short, you damage the commutators.
- Running at too high rpm for long.
Over-revving is another leading cause of a burnt-out brushless motors system. Usually, you can run your RC car above 30% of its rated speed. However, when you exceed this speed limit, you risk causing electrical and mechanical damage to it. First, your damaged electric components of the winding as when run at high speeds, the winding may eventually burn.
On the other hand, mechanical damage arises when the centrifugal force of your rotor increases. This causes the shaft to break apart, causing the motor to also explode.
- Damaged bearing
Another problem that causes the brushless motor to fail is a faulty bearing. Why? The bearings of your motor are the parts that work the most. Hence, they usually get worn out faster than other parts.
By continuously using a damaged bearing, you invariably slow your brushless motor. But how do you know when your bearings are damaged? Check to see if you can turn the shafts swiftly. If so, your bearings are damaged.
- Too much load
Your brushless motor has a projected voltage range it works on. When you use it above that value, it reduces its lifespan. Apart from this, too much load on your brushless motor can cause increased power consumption and overheating the RC motor.
Also, the excessive load will lead to a high voltage, which can also break through the insulation of the windings and cause a short circuit. This short circuit will eventually lead to excessive current, which may cause the RC motor to burn.
However, the good news is that it takes longer for excessive current to kill a brushless motor. You need to make sure that the voltage range of your brushless RC motor falls between 0.3 to 0.8 ohms. If it goes higher than this, it can also cause the wire to burn.
Is an old brushless motor more likely to burn?
If you have an old brushless motor, the chances are that it might burn out on your next run if there is insulation failure, bearing wear, rotor failure due to fatigue and a harsh operating environment.
Your old brushless motor will also burn if you run them on too high voltages and current as this may cause them to overheat. The good news is that you can still use your old brushless motor longer if you know how to maintain the speed, temperature and bearings.
Do brushless motors last forever?
Unlike brushed motors, which have an efficiency rate between 70% to 80%, brushless motors typically have an efficiency of 85%-90%. They are also super light, produce less noise and have a longer life expectancy than brushed motors.
In fact, you can use your brushless motors for more than ten thousand hours before they burn out, unlike the brushed motors that only last between 1000 to 3000 hours,
Should you cool a brushless motor?
Yes, your brushless motors need adequate cooling to perform functionally.
Excessive temperatures will cause the motor’s performance to drastically reduce or even fail on the track without the right cooling. The last thing you want is to end up stuck in the middle of the track when driving your RC car.
You can cool your brushless motor by ensuring proper ventilation through RC fans, heat sinks, or cutting out small body sections. Upgrading the bearings to ensure the motor turns efficiently also lessens the heat. Stainless steel and ceramic bearings are two of the best bearing devices decrease that help decrease rolling resistance, which improves motor temperature and makes your motor run longer and more efficient.
Learn how to cool your RC: Do RC motor heat sinks actually work (do you need one?)
Brushless motors can indeed burn out. But, the cause, you can never fully know because the reasons behind your brushless motor burning vary with how you use it. To prevent a burnt-out motor, you need to fully understand the impact of how your actions can cause the motor to burn out. Hopefully, this guide has provided you with the most reasonable reason a brushless motor might burn out and how to prevent it.