Providing Power, Direction and Speed Control
Wiring the Motors, DPDT Relays and PWM to the MOSFET
The diagram above shows how I wired four of the DPDT relays (on my eight relay board) to control the direction and speed of the motors for the Rover's wheels.
A logic level, power N-MOSFET switches up to 8A (10A absolute max) to provide motive power at 12vdc vdc. The gate is controlled by an Arduino PWM pin so speed can be adjusted accordingly. However each individual relay is only capable of switching 2A at 12vdc, but that can give me 24watts, per wheel in theory.