Pavel, hopefully you are still active on this forum. I just began using the Pololu sensor, in my case the +-5A unit. I find that the sensor is affected by the earth's magnetic field, as rotating the sensor is causing a very repeatable drift of about 10 counts over the orientation range. I've relocated the sensor and processor (about 1 foot apart) from various sources of EMF (laptop, desk lamps, etc), and the A/D output is identical other than the orientation effect and the typical +-1 count of jitter.
Do you have any experience with this effect (earth's magnetic field), or with shielding for these boards?
Thanks,
-Chris
pavelp:
Hello jimfordI use the Arduino with Pololu Current Hall sensors (Pololu 1186) for remote network current measurement.
Pololu - ACS715 Current Sensor Carrier 0 to 30AI see your sensor has 5V operating voltage:
Try this:
be sure the sensor-arduino cables are as short as possible
connect the sensor Vcc to the Arduino Analog Reference pin (NOT to other 5V pins or external source!!)
connect the sensor OUT with a shielded cable (shield to GND)
try several GND Arduino pins for sensor GND pin connection to minimize the jitter, it should be the GND pin with physically shortest connection to the A/D converter IC
try to more stabilize the arduino main voltage, the usb connection only may not be sufficientThe digital A/D output ripple should be in WORST CASE not over +-1, for example 511,512,513
Hope this helps
Regards
Pavel