Siemens SIMATIC S7-1200

Technology instructions
10.3 Motion control
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
747
10.3.7.8
MC_MoveVelocity (Move axis at predefined velocity)
Table 10- 68 MC_MoveVelocity instruction
LAD / FBD
SCL
Description
"MC_MoveVelocity_DB"(
Axis:=_multi_fb_in_,
Execute:=_bool_in_,
Velocity:=_real_in_,
Direction:=_int_in_,
Current:=_bool_in_,
PositionControlled:=_bool_in_,
InVelocity=>_bool_out_,
Busy=>_bool_out_,
CommandAborted=>_bool_out_,
Error=>_bool_out_,
ErrorID=>_word_out_,
ErrorInfo=>_word_out_);
Use the MC_MoveVelocity instruc-
tion to move the axis constantly at
the specified velocity.
In order to use the
MC_MoveVelocity 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_MoveVelocity_DB " is the name of the instance DB.
Table 10- 69 Parameters for the MC_MoveVelocity instruction
Parameter and type
Data type
Description
Axis
IN
TO_SpeedAxis
Axis technology object
Execute
IN
Bool
Start of the task with a positive edge (Default value: False)
Velocity IN Real Velocity specification for axis motion (Default value: 100.0)
Limit values: Start/stop velocity ≤ |Velocity| ≤ maximum velocity
(Velocity = 0.0 is allowed)
Direction IN Int Direction specification:
• 0: Direction of rotation corresponds to the sign of the value in
parameter "Velocity" (Default value)
• 1: Positive direction of rotation (The sign of the value in param-
eter "Velocity" is ignored.)
• 2: Negative direction of rotation (The sign of the value in pa-
rameter "Velocity" is ignored.)
Current IN Bool Maintain current velocity:
• FALSE: "Maintain current velocity" is deactivated. The values
of parameters "Velocity" and "Direction" are used. (Default val-
ue)
• TRUE: "Maintain current velocity" is activated. The values in
parameters "Velocity" and "Direction" are not taken into ac-
count.
When the axis resumes motion at the current velocity, the "In-
Velocity" parameter returns the value TRUE .