Electronic – arduino – connect multiple brushless motors and ESC’s to a single GND in Arduino Uno

arduinobrushless-dc-motorgroundmotor controller

The main aim is to connect 4 motors in parallel each with separate ESC's to a single GND. I want to do this because there is a limited number of GND sockets built in the Arduino microcontroller. I have made a simple schematics that is hopefully a functioning parallel connections of the ESC, motors and batteries. Would this theme work for its purpose?A schematics showing 2 motors each with ESC's connected in parallel

There is one wire directly from one of the ESC's to the GND socket in the Arduino. Then below that another the GND wire from the next ESC joins with the main wire down to the GND socket on the Arduino board. Please note that the +5v wires from the ESC's are left disconnected to anything. Obviously, the signal wire to the digital I/O on the Arduino board are separate for each set of motor and ESC. The three wires from the brushless motors are connected to the ESC's as per normal.

Would this work? Or are the wiring from the motor to the ESC dysfunctional?

Best Answer

In your diagram the power supplies are wired in series 'back-to-back' so the top ESC is only getting the difference between their voltages. Most ESCs have their signal ground connected to battery negative internally. If the signal grounds are connected together and there is a significant voltage difference between them (eg. because the power supplies are in series), a large current could flow which may burn out the wires and/or destroy the Arduino.

Each power supply should be wired to each ESC separately. The ground wires of each ESC signal lead must go to Arduino ground. Powering each ESC from a separate PSU ensures that motor current won't try to go through the signal leads.

enter image description here

If you want to power two ESCs from the same PSU then make sure that the negative battery wires are firmly connected to the PSU with short thick wires. If the negative battery lead of an ESC becomes disconnected then it will draw power through the signal ground wire from the other ESC (not good if your motors are drawing high current!).

Related Topic