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ACS711EX/+-31A problem


Hi, I have a couple of ACS711EX -31A;+31A current sensors. I connected them like in the wiring diagram on your website. Supply voltage is 5V. When there is no current, output voltage is stable 2.5V. When I apply +2A of current, VOUT goes down to 1.6V. When I apply -2A (reverse direction), VOUT goes down to 1.3V. I even try connecting 1nF and 15kohm between VOUT and GND (as said in datasheet). This testing was done on my workdesk, inside my flat, so no heavy EM environment expected.

I tested it also with 3.3V and same thing happens - to large of a voltage drop for only 2A of current.

Sensors were ordered from HobbyTronics, IC chip number is 711 1341 662M.

Can you please help me. What am I doing wrong?

Thank you in advance!


I am sorry you are having trouble getting your current sensors to work. Can you tell me more about your setup? What are you using to supply 5V and 3.3V power? How are you measuring or reading the output? What are you using as your 2A load? Can you post pictures that clearly show your setup and connections to the board? Also, do all of your current sensors exhibit the same behavior?