MC_MoveRelative

This FB serves to carry out a relative positioning. After reaching the target position, the axis is at standstill if no further motion commands are pending.

		MC_MoveRelative
AXIS_REF	-	Axis	Done	-	BOOL
BOOL	-	Execute	Busy	-	BOOL
BOOL	-	ContinuousUpdate	Active	-	BOOL
LREAL	-	Distance	CommandAborted	-	BOOL
LREAL	-	Velocity	Error	-	BOOL
LREAL	-	Acceleration	ErrorID	-	L_IE1P_Error
LREAL	-	Deceleration
LREAL	-	Jerk
MC_BUFFER_MODE	-	BufferMode

Inputs

Name Data type	Information/possible settings
Axis AXIS_REF	Transfer of the axis data structure Motion axes (AXIS_REF)
Execute BOOL	FALSE ä TRUE	Start positioning.
ContinuousUpdate BOOL	Continuous acceptance of the profile parameters Control input ContinuousUpdate
FALSE	The profile parameters ( Distance , Velocity , Acceleration , ...) are accepted with a rising edge at Execute .
TRUE	The profile parameters are accepted continuously, i.e. during the execution, the motion profile may change.
Distance LREAL	Distance to be traversed in [unit] With reference to the set position at the starting time of the command.
Velocity LREAL	Maximum velocity in [unit/s] for approaching the target position Depending on the profile parameters Position , Acceleration, Deceleration and Jerk , the drive may not reach the maximum velocity. Special case : Velocity = 0: The default value defined in subindex 40 is used for the velocity.
Acceleration LREAL	Maximum acceleration in [unit/s ² ] Special case : Acceleration = 0: The default value defined in subindex 41 is used for the acceleration.
Deceleration LREAL	Maximum deceleration in [unit/s ² ] Special case : Deceleration = 0: The default value defined in subindex 41 is used for the acceleration.
Jerk LREAL	Maximum jerk in [unit/s ³ ] Special case : Jerk = 0: The default value defined in subindex 43 is used for the jerk.
BufferMode MC_BUFFER_MODE	Mode for processing successive motion commands BufferMode

Name

Data type

Information/possible settings

Axis

AXIS_REF

Transfer of the axis data structure

Motion axes (AXIS_REF)

Execute

BOOL

FALSE ä TRUE

Start positioning.

ContinuousUpdate

BOOL

Continuous acceptance of the profile parameters

Control input ContinuousUpdate

FALSE

The profile parameters ( Distance , Velocity , Acceleration , ...) are accepted with a rising edge at Execute .

TRUE

The profile parameters are accepted continuously, i.e. during the execution, the motion profile may change.

Distance

LREAL

Distance to be traversed in [unit]

With reference to the set position at the starting time of the command.

Velocity

LREAL

Maximum velocity in [unit/s] for approaching the target position

Depending on the profile parameters Position , Acceleration, Deceleration and Jerk , the drive may not reach the maximum velocity.

Special case :

Velocity = 0: The default value defined in subindex 40 is used for the velocity.

Acceleration

LREAL

Maximum acceleration in [unit/s ² ]

Special case :

Acceleration = 0: The default value defined in subindex 41 is used for the acceleration.

Deceleration

LREAL

Maximum deceleration in [unit/s ² ]

Special case :

Deceleration = 0: The default value defined in subindex 41 is used for the acceleration.

Jerk

LREAL

Maximum jerk in [unit/s ³ ]

Special case :

Jerk = 0: The default value defined in subindex 43 is used for the jerk.

BufferMode

MC_BUFFER_MODE

Mode for processing successive motion commands

BufferMode

Outputs

Name Data type	Value/meaning
Done BOOL	TRUE	Positioning completed successfully.
Busy BOOL	TRUE	Processing is running.
Active BOOL	TRUE	The command of the FB is currently executed. The Active output matters if a motion control is carried out by several FBs (BufferMode).
CommandAborted BOOL	TRUE	The command was aborted by another FB.
Error BOOL	TRUE	An error has occurred. For details see ErrorID .
ErrorID L_IE1P_Error	If Error = TRUE: Error number for the error that has occurred.

In the following example, two FB instances of MC_MoveRelative are connected in series as a cascade.

Case

: FB2 will only be started after FB1 has reached its commanded distance "6000" (with a velocity = "0").

The Done output of FB1 starts the execution of FB2.

FB2 traverses the axis by the commanded distance "4000".

Case

: FB2 is started (by means of a test signal) before FB1 has reached its commanded distance.

The execution of FB1 is aborted ( CommandAborted = TRUE).

FB2 adds the distance "400" to the current position "3250" and traverses the axis to the resulting position "7250".

Example: Linking two MC_MoveRelative commands