FC_RestoreAxisPosition

FC_RestoreAxisPosition - General Information

Overview

Type:	Function
Available as of:	V1.0.3.0
Versions:	Current version

Task

Restoring the axis position after switching the PacDrive controller on/off

Description

With this function, the axis position can be maintained after a PacDrive controller on/off switching procedure. It is not necessary to take the encoder period or ratio of the feed constant, the gear factor (GearIn, GearOut) and the machine period into consideration.

The use of a gear with the resolution 2ⁿ is not necessary. It is a condition for using this function that the encoder has not been turned by more than half of its maximum value range (encoder period) while the PacDrive controller was turned off. The function is unable to recognize when the encoder is moved out of this range and so therefore cannot generate an error. In this case, a FALSE position is restored.

The axis position and the encoder position are saved in remanent variables in the NVRam using the FC_SaveAxisPosition() function. The function must be called cyclically.

By means of the function FC_RestoreAxisPosition(), the remanent variables are re-read and the axis position is calculated and set. The function should only be called up once.

By means of the PacDrive LMC Pro, the remanent memory area is buffered using batteries.

Interface

Input	Data type	Description
i_ifDrive	IF_Drive	Input for the axis that shall be controlled.
i_lrUserPeriod	LREAL	Machine period
i_lrRestoreWindow	LREAL	Maximum permissible deviation between the saved and the restored axis positions.
iq_stRestorePosition	ST_AxisRestorePosition	Remanent data

Output	Data type	Description
q_etDiag	GD.ET_Diag	General library-independent statement on the diagnostic. A value not equal to ET_Diag.Ok corresponds to an diagnostic message.
q_etDiagExt	ET_DiagExt	POU-specific output on the diagnostic. q_etDiag = ET_Diag.Ok -> Status message q_etDiag <> ET_Diag.Ok -> Diagnostic message
q_sMsg	STRING[80]	Event-triggered message which gives more detailed information on the diagnostic state.

Output

Data type

Description

q_etDiag

GD.ET_Diag

General library-independent statement on the diagnostic.

A value not equal to ET_Diag.Ok corresponds to an diagnostic message.

q_etDiagExt

ET_DiagExt

POU-specific output on the diagnostic.

q_etDiag = ET_Diag.Ok -> Status message

q_etDiag <> ET_Diag.Ok -> Diagnostic message

q_sMsg

STRING[80]

Event-triggered message which gives more detailed information on the diagnostic state.

Diagnostic Messages

q_etDiag	q_etDiagExt	Enumeration value	Description
OK	Ok	0	Ok
DriveConditionInvalid	DriveEncoderInvalid	175	The drive encoder is invalid.
DriveConditionInvalid	OutOfRestoreWindow	195	The position is outside the restore window.
DriveConditionInvalid	RestoreInterrupted	196	Restoring was interrupted.
InputParameterInvalid	CheckSumInvalid	193	The checksum is invalid.
InputParameterInvalid	DataNVRamInvalid	194	The non-volatile memory (NVRam) does not contain any more valid data.
InputParameterInvalid	DriveInvalid	3	The connected drive is invalid.
SercosConditionInvalid	SercosNotInPhaseFour	19	The Sercos bus is not in phase 4.
UnexpectedProgramBehavior	UnexpectedFeedback	1	An unintended detected error occurred during execution.

CheckSumInvalid

Enumeration name:	CheckSumInvalid
Enumeration value:	193
Description:	The checksum is invalid.

Issue	Cause	Solution
-	The data stored in i_stRestorePosition are inconsistent. The position cannot be restored.	New homing of the drive required.

DataNVRamInvalid

Enumeration name:	DataNVRamInvalid
Enumeration value:	194
Description:	The non-volatile memory (NVRam) does not contain any more valid data.

Issue	Cause	Solution
-	The data stored in the NVRam are invalid. Therefor, the position cannot be restored from i_stRestorePosition.	Verify the NVRam, verify the buffer battery and replace if necessary. New homing of the drive required.

Issue

Cause

Solution

The data stored in the NVRam are invalid. Therefor, the position cannot be restored from i_stRestorePosition.

Verify the NVRam, verify the buffer battery and replace if necessary.

New homing of the drive required.

DriveEncoderInvalid

Enumeration name:	DriveEncoderInvalid
Enumeration value:	175
Description:	The drive encoder is invalid.

Issue	Cause	Solution
-	The axis encoder is not supported.	Use an axis with a different encoder.

DriveInvalid

Enumeration name:	DriveInvalid
Enumeration value:	3
Description:	The connected drive is invalid.

Issue	Cause	Solution
-	At the input i_ifDrive, no drive was applied.	At the input i_ifDrive, a valid drive must be transferred.
-	The connected drive does not support all required functionalities.	Establish which functionalities are not supported by the drive by means of output q_sMsg. Use a drive which supports all required functionalities.

Issue

Cause

Solution

At the input i_ifDrive, no drive was applied.

At the input i_ifDrive, a valid drive must be transferred.

The connected drive does not support all required functionalities.

Establish which functionalities are not supported by the drive by means of output q_sMsg.

Use a drive which supports all required functionalities.

Enumeration name:	Ok
Enumeration value:	0
Description:	Ok

The axis position has been restored successfully.

OutOfRestoreWindow

Enumeration name:	OutOfRestoreWindow
Enumeration value:	195
Description:	The position is outside the restore window.

Issue	Cause	Solution
-	The axis has been moved too far since the last time the position has been saved.	Set the axis position back into the window. Extend the limits of the window i_lrRestoreWindow.

Issue

Cause

Solution

The axis has been moved too far since the last time the position has been saved.

Set the axis position back into the window.

Extend the limits of the window i_lrRestoreWindow.

RestoreInterrupted

Enumeration name:	RestoreInterrupted
Enumeration value:	196
Description:	Restoring was interrupted.

Issue	Cause	Solution
-	Reading the encoder has been interrupted repeatedly by the SERCOS.	Ensure that the execution of the function is not interrupted for too long by other tasks, so that it can be interrupted by the SERCOS task only once.

SercosNotInPhaseFour

Enumeration name:	SercosNotInPhaseFour
Enumeration value:	19
Description:	The Sercos bus is not in phase 4.

Issue	Cause	Solution
-	The parameter State of the SERCOS bus is not 4.	Set the SERCOS bus parameter PhaseSet to 4. Verify the SERCOS bus for errors.

Issue

Cause

Solution

The parameter State of the SERCOS bus is not 4.

Set the SERCOS bus parameter PhaseSet to 4.

Verify the SERCOS bus for errors.

UnexpectedFeedback

Enumeration name:	UnexpectedFeedback
Enumeration value:	1
Description:	An unintended detected error occurred during execution.

Issue	Cause	Solution
-	An error occurred in the internal execution.	Please inform the support team about this error.