This current sensor board is based on the Allegro ACS712ELCTR-30A bi-directional hall-effect current sensor chip that detects positive and negative flowing currents in the range of minus 30 Amps to positive 30 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 66mV per amp for positive current or down -66mV per amp for negative current.  

For example: 

The output voltage at +2 amps would be (2.5V + (0.066 * 2)) = 2.632 V 
The output voltage at -5 amps would be (2.5V - (0.066 * 5)) = 2.170 V

Feature :

• The current sensor chips: acs712elc-20a;
  
• Pin 5 V power supply on board power indicator;
  
• The module can measure the positive and negative 20 amps, corresponding to the analog output of 100mv / a;
  
• No test current through the output voltage is VCC / 2;
  
• PCB board size: 31 (mm) x13 (mm);
  
• Color: as the photos show.
  
• Note: ACS712 is based on the principle of the Hall test, please use this field to avoid impact
  
• Note: Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!
  

Packing:

• Current sensor module x 1pcs

SPECIFICATIONS: 

VCC	5V DC Nominal
Measurement Range	-30 to +30 A
Voltage at 0A	VCC/2 (Nominally 2.5V DC)
Scale Factor	66 mV per A
Dimensions:
Length	31.73 mm (1.24")
Width	13.25 mm (0.52")
Height	14 mm (0.55")
Weight	2.72 g (0.096 oz)