Gas meter monitor

Monitor gas consumption using a hall effect sensor.

519 : south/north : 522.24/501.76 : 2.54 518 : south/north : 522.24/501.76 : 2.53 516 : south/north : 522.24/501.76 : 2.52 514 : south/north : 522.24/501.76 : 2.51

512 : south/north : 522.24/501.76 : 2.50 << Point at which 0 passes front window

513 : south/north : 522.24/501.76 : 2.51 514 : south/north : 522.24/501.76 : 2.51 516 : south/north : 522.24/501.76 : 2.52 518 : south/north : 522.24/501.76 : 2.53 519 : south/north : 522.24/501.76 : 2.54 519 : south/north : 522.24/501.76 : 2.54

Test above done using an Arduino running at 5v rather than 3.3v as per the target final version. But principle will be exactly the same, but without the sensor plugged in to a breadboard and held as close as possible to the gap underneath the meter wheel. Honeywell SS49E Hall sensors from RS are giving base readings of 519-521 (519 for sensor tested above). I'll set the trigger point at 515 and with the sensor closer to the sensor this should be fine to detect the north pole magnet moving past the sensor.