This current sensor board is based on the Allegro ACS712ELCTR-05A bi-directional hall-effect current sensor chip that detects positive and negative flowing
currents in the range of minus 5 Amps to positive 5 Amps. The board operates at 5V DC and the current flow through the sensor is converted to an output
voltage starting at 1/2Vcc (or 2.5V) for no current flow and moves up 185mV per amp for positive current or down -185mV per amp for negative current.
The output voltage at +2 amps would be (2.5V + (0.185 * 2)) = 2.870 V
The output voltage at -5 amps would be (2.5V - (0.185 * 5)) = 1.575 V