Program the Master controller Ver3.
Start mounting the Jumper JP3 on the PCB.
Power up the controller.
The controller now show's a number , indicating the speed step, from 04-30.
Turn up the speed to Max.
Then adjust the potentiometer, until the display show "30" .
It may shift between 29 and 30, but NOT show 31.
There should be a place on the potentiometer where the display show "30", place it in the middle of that.
Then turn the speed down to zero, now it should say "04" in the display.
If the number is bigger then R19 have to be replaced with a smaller resistor.
If you change R19, you have to make the max. calibration again.
When the calibration is finish, turn off the power , remove the jumper, and it is finish to use.