This Module is Based on Allegro Hall effect Based Linear Current Sensor IC ACS758LCB-050B. This is 50 Ampere Bi-directional current sensor Module.
The relationship between voltage output and current input:
VOUT = VOUT(Q) + Vsens x I VOUT(Q) is the quiescent output voltage, which is VCC/2, which is the output voltage when there is no input. Vsens is a sensor-sensitive scale, also known as a coefficient. I is the current flowing from IP+ to IP-.
For example, suppose the sensor model is 050B, VCC is 5V, and I current is 10A, then the output is 5V / 2+40mV/A x10A=2.9V.