ESC Part 1 – Pilot

What is ESC?

If you are hobbyist, then you know what is ESC. But if you are new in this hobby then you might not. What is ESC? ESC is a simple electronic component, which controls the speed of motor depending on the signal that is provided to it. Very much like the fan regulator that we have in our home. But instead of manually rotating the dial there is a digital signal.

Lets understand what it is and how it works, first check at the following image.

ESC diagram

Every ESC has 4 parts: Input, Output, Signal,BEC*

Input is used to provide input voltage, every ESC has a limited input range. Like 2S-3S (7.4V – 12V) or 3S to 4S (12V – 16V) before using or connecting input voltage its better you check what its operating range is.

Output is used to provide output signals to motor. If you are using a brushless esc then it would be used to control brushless motors and if its brushed esc then it would be used to control a brushed motor. Its simple, just connect each wires coming out of esc to motors. Point or very important point to notice is MAX A capacity of the ESC and the motor’s max A consumption.

If your motor consumes a 15A then its better to use a ESC which can provide 15A or more (its better to have a good extra buffer). Any bigger value ESC you can use but not lower. Another important point to note when you choose an esc is its max capacity. Every ESC is categorised on its A rating.

150A – 20/25A
and then 30A the most commonly used and most recommended.
And then upwards.

We have so far understood what is input and what is output. But how output is controlled? and this is the important point and why we use ESC. Every esc has a signal input wire. Its nothing but a PWM digital signal which ranges from 1 micro sec to 2 micro sec (depends on the controller) depending on the signal that it receives ESC varies the output to motor and controls the speed of motor. Easy as its sounds right? yea it is! Every esc has a micro controller in it, which has a program which does this job. This program is also called as firmware, for basic and beginners the default firmware is more than good. But if you advanced flyer and need more out of your esc then you can flash or program your esc with another firmware there are many available. We will see this part in more detail in our next blog.

The last part of the ESC is BEC (battery eliminator circuit) which is optional component, i.e. it might be a part of ESC or not. Many ESC which don’t have BEC are called as OPTO. BEC is a small circuit which provides a +5v from the ESC. This +5V can be used to power controller or receiver or servo. But the downside of having BEC is it makes the esc heavy. Now a days you get small BEC circuit externally and you don’t have to use one from the esc. This saves a lot of space and very important decreases weight.

That’s all for the part 1, I hope I have explained in detail about ESC and basic about it. In our next part 2, we will focus on the firmware that is used to control the speed of the motor and how it helps to have a better firmware.

Written by on April 21, 2016