This circuit indicates the current of a motor or other load. Resistor R has values between 470 ohm and 1 k ohm. With 1N4002 diodes we can monitor loads up to 1 A. The circuit is from the book Robotics, Mechatronics and Artificial Intelligence by Newton C. Braga. The supply voltage can typically be between 12 and 15 V. At lower voltages, the drop in the diode can affect the load supply.
