L_MC1P - MC_MoveAbsolute: For target positions > 360°, the selected direction of rotation is not observed as expected (corrected from V3.13.0)
Corrected from: Library: L_MC1P_MotionControlBasic (FAST Motion) V03.13.00.38 (contained in the PLC Designer from V03.13.00)
Response of the new version:
Behaviour of MC_MoveAbsolute when using a modulo axis
Example: Modulo cycle = 360 units = 360°
StartPos
Targetpos
Motion
StartPos
Targetpos
Motion
StartPos
Targetpos
Motion
MC_DIRECTION
mcCurrentDirection := 0,
0
0
no motion
0
360
no motion
0
720
no motion
mcPositiveDirection := 1,
0
0
no motion
0
360
no motion
0
720
no motion
mcNegativeDirection := 2,
0
0
no motion
0
360
no motion
0
720
no motion
mcShortestWay := 3,
0
0
no motion
0
360
no motion
0
720
no motion
mcPositiveCycle := 11,
0
0
no motion
0
360
+360°
0
720
+720°
mcNegativeCycle := 12
0
0
no motion
0
360
-360°
0
720
-720°
StartPos
Targetpos
Motion
StartPos
Targetpos
Motion
StartPos
Targetpos
Motion
MC_DIRECTION
mcCurrentDirection := 0,
0
90
+90°
0
300
+300°
0
450
+90°
mcPositiveDirection := 1,
0
90
+90°
0
300
+300°
0
450
+90°
mcNegativeDirection := 2,
0
90
-270°
0
300
-60°
0
450
-270°
mcShortestWay := 3,
0
90
+90°
0
300
-60°
0
450
+90°
mcPositiveCycle := 11,
0
90
+90°
0
300
300°
0
450
+450°
mcNegativeCycle := 12
0
90
-270°
0
300
-60°
0
450
-630°
What happens?
In the modulo measuring system, the target position is not approached as expected.
Example: - The modulo axis is at position 0 units. - The MC_MOVEABSOLUTE FB shall be used to travel to the target position 370 units, with negative direction of rotation.
- Actually, it is positioned to position 10 with positive direction of rotation.
When does this behaviour occur?
Modulo measuring system and
target position > 360° (modulo cycle) and
negative direction of rotation is selected
Which products are affected? Library: L_MC1P_MotionControlBasic (FAST Motion) (contained in the PLC Designer)
Short-term measures:
Select target positions smaller than one modulo cycle or use the 'MC_MoveRelative' FB.
