What are the controlling input specifications of a Hobbywing Quicrun WP-1040 Electronic Speed Controller (ESC) for brushed motors? I assume it should use the standard PWM with 1 kHz frequency as stated in its manual? Do I have to find the "pulse length to motor speed/direction translation" by myself or are there any common conventions?
I want to use the ESC directly without a radio receiver to drive a Himoto RC540 26T motor in an RC car (Himoto Short Course Corr Truck 4WD RTR 1:10).
Generally all RC gear uses the same old pulse-width modulation scheme: a pulse whose length varies between 1 and 2 ms, repeating every 20 ms.
A pulse of 1 ms means "motor off"(airplane ESCs), "full reverse"(car ESCs) or "servo to the extreme left/right", while a pulse of 2 ms means "motor to full power" or "servo to the other extreme end".
The 1 kHz specification in the manual is about the motor output. The ESC switches the H bridge MOSFETS at 1 kHz at varying duty cycles in order to precisely control the motor speed.
A period of 20 ms means a frequency of 50 Hz, not 1 kHz like you assumed. Some components like RC helicopter tail rotor servos and multicopter ESCs are designed to also accept non-standard, higher frequency signals (500 Hz or less) for tighter control loops.
