Siemens SIMATIC S7-1200

Technology instructions
10.3 Motion control
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
745
10.3.7.7
MC_MoveRelative (Position axis relatively)
Table 10- 66 MC_MoveRelative instruction
LAD / FBD
SCL
Description
"MC_MoveRelative_DB"(
Axis:=_multi_fb_in_,
Execute:=_bool_in_,
Distance:=_real_in_,
Velocity:=_real_in_,
Done=>_bool_out_,
Busy=>_bool_out_,
CommandAborted=>_bool_out_,
Error=>_bool_out_,
ErrorID=>_word_out_,
ErrorInfo=>_word_out_);
Use the MC_MoveRelative instruc-
tion to start a positioning motion
relative to the start position.
In order to use the
MC_MoveRelative instruction, the
axis must first be enabled.
1
STEP 7 automatically creates the DB when you insert the instruction.
2
In the SCL example, "MC_MoveRelative_DB " is the name of the instance DB.
Table 10- 67 Parameters for the MC_MoveRelative instruction
Parameter and type
Data type
Description
Axis
IN
TO_Axis_1
Axis technology object
Execute
IN
Bool
Start of the task with a positive edge (Default value: False)
Distance IN Real Travel distance for the positioning operation (Default value: 0.0)
Limit values: -1.0e
12
≤ Distance ≤ 1.0e
12
Velocity IN Real Velocity of axis (Default value: 10.0)
This velocity is not always reached on account of the configured
acceleration and deceleration and the distance to be traveled.
Limit values: Start/stop velocity ≤ Velocity ≤ maximum velocity
Done OUT Bool TRUE = Target position reached
Busy
OUT
Bool
TRUE = The task is being executed.
CommandAborted
OUT
Bool
TRUE = During execution the task was aborted by another task.
Error OUT Bool TRUE = An error has occurred during execution of the task. The
cause of the error can be found in parameters "ErrorID" and "Error-
Info".
ErrorID
OUT
Word
Error ID for parameter "Error" (Default value: 0000)
ErrorInfo
OUT
Word
Error info ID for parameter "ErrorID" (Default value: 0000)