Hello, I am using a cnc shield V.3 with four A4988 drive tuned to provide maximum 1.8 A (each drive) and a lab power supply (30V-10A set to operate at 12 V). The configuration hase four motors: 1X axis, 1 Z axis and Y axis is cloned (2 motor for the same axis). I have noticed that no matter which axis I am moving (or if I am moving XY together) the same current is drawn from the power supply (1.8A). I am commanding the system with UGS.
I would expect instead that:
-When I move X axis (1 motor alone) I should see 1.8 A consumption
-When I move Y axis( two motors) I should see 3.6 A consumption
-When I move XY together (3 motors) I should see 5.4 A consumption
If I see always 1.8A this should mean that when more axis are moving togheter (i.e. XY diagonal motion) each motor is drawing less current, so a lower holding torque is available which means lower feed force.
Does anyone know why this is happening and what I need too do to fix this?