Which products are affected?
ESP-SPAC-CAM1 – Software Package Cam V1.5 (LenzeCamControl1V0105.lib library)
What happens?
The actual position is indicated incorrectly at the L_CamControl (
L_CamControl.dnActPos_p signal) after mains connection.
When does the problem occur?
The problem occurs under the following conditions:
- The motor mounting position is inverted (L_CamControl.bMotMountingOrientation = TRUE) and
- The position feedback system is an absolute value feedback system (i.e. resolver, single-/multi-turn absolute value encoder) and
- The user program uses the 'Save home position' functionality (if the cam template was used this function would correspond to the 'Set home position' function executed via the g_bHomePositionSet global template variable), i. e. homing is not required after mains connection.
Possible diagnostics?
The behaviour can be diagnosed if before mains connection the position value at the
L_CamControl.dnActPos_p signal differs from the one after voltage recovery although the drive has not changed its position while being disconnected from the mains.
Short-term measures/recommendations?
Since the problem only occurs if the inverted motor mounting position (
L_CamControl.bMotMountingOrientation = TRUE) has been selected another method than the function block variable is to be chosen for the speed inversion. The following options are available:
- mechanical modification of the system in order to be able to operate the motor directly
- inverting the signals at the L_CamControl.nMainIn_v, L_CamControl.dnSubYEndMain_p, L_CamControl.nAuxIn_v and L_CamControl.dnSubYEndAux_p inputs: In the cam template this can be done by e. g. inverting the y-stretching/ compression factor. In addition the signals for manual homing, homing and positioning are to be exchanged in direction of rotation if the cam template is used.
Evaluation:
The problem occurs if the motor mounting position has been inverted and absolute value encoders are used at the same time for keeping the home position beyond the mains disconnection phase. In this case a deviation may occur when the actual position is determined after voltage recovery. External measures (hardware limit switch, sensors) reveal this behaviour. During initial commissioning this behaviour is also detected and can be avoided by applying the
Short-term measures/recommendations mentioned before.
