MC_Halt

PLCopen motion icon

Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. - Decelerates an axis to zero velocity For a group of axes this means: In ACS the velocities of the different axes. In MCS and PCS it provides the velocity of the TCP.

Inputs

Input	Data Type	Range	Unit	Default	Description
Execute	BOOL	0, 1	N/A	No default	On the rising edge The transition of a digital signal from low to high. AKA: positive edge., request to queue the move.
Axis	AXIS_REF	1, 256	N/A	No default	Name of a declared instance of the AXIS_REF library function A function calculates a result according to the current value of its inputs. A function has no internal data and is not linked to declared instances.. See Axis Name and Number. See AXIS_REF Structure.
Deceleration	LREAL	No range	User unit/sec²	No default	Trapezoidal: Deceleration rate. S-curve: Unused. See S-curve and Trapezoidal Acceleration / Deceleration.
Jerk In physics, jerk is the rate of change of acceleration. More precisely, the derivative of acceleration with respect to time.	LREAL	No range	User unit/sec³	No default	Trapezoidal: 0 (zero). S-curve: Constant jerk. See S-curve and Trapezoidal Acceleration / Deceleration.
BufferMode	SINT	0, 5	N/A	No default	0 = Abort. 1 = Buffer. 2 = Blend A way that consecutive function blocks cooperate in the transition from the first to the next. to active. 3 = Blend to next. 4 = Blend to low velocity. 5 = Blend to high velocity. See Buffer Modes.

Outputs

Output	Data Type	Range	Unit	Description
Done	BOOL	No range	N/A	Indicates the move completed successfully. The Command Position Position means a point in space which is described by different coordinates. Depending on the used system and transformation it can consist of a maximum of six dimensions (coordinates).This means three Cartesian coordinates in space and coordinates for the orientation. In ACS there can be even more than six coordinates. If the same position is described in different coordinate systems the values of the coordinates are different. has reached the endpoint.
Busy	BOOL	No range	N/A	High from the moment the Execute input goes high until the time the move is ended.
Active	BOOL	No range	N/A	Indicates this move is the Active move.
CommandAborted	BOOL	No range	N/A	Indicates the move was aborted.
Error	BOOL	No range	N/A	Indicates either: An invalid input was specified. The move was terminated due to an error.
ErrorID	INT	No range	N/A	Indicates the error if the Error output is set to TRUE. See PLCopen Function Block ErrorIDs.

Remarks

This function block starts a motion-related action and stores data for calculations and error checking.
See Call Function Blocks Multiple Times in the Same Cycle if using a dual-core controller.

See Function Blocks - General Rules about how inputs and outputs work.
It is a queued single-axis move.
- The move is complete when the axis reaches zero velocity.
It is typically used with Abort at the BufferMode input to terminate a move.
See MC_Stop to execute a stop that cannot be aborted.
See Main about how this function is used in the Hole punch project.

Figure 1: MC_Halt

Time Diagram

This example shows the behavior in combination with a MC_MoveVelocity.

A rotating axis is ramped The gradual acceleration and deceleration of a stepping motor. This is essential if performance beyond the start/stop range is required. The slope of the ramp is a function of screw pitch, load, drive voltage and design, and motor. down with FB2 MC_Halt.
Another motion command overrides the MC_Halt command.
- MC_Halt allows this, in contrast to MC_Stop.
The axis can accelerate again without reaching standstill.

Figure 2: Time Diagrams: First and Second FBs

Figure 3: Time Diagram

FBD Language Example

Not available.

FFLD Language Example

IL Language Example

Not available.

ST Language Example

(* MC_Halt ST example *)
Inst_MC_Halt( HaltReq, Axis1,100.0, 100.0, 0 );
//Inst_MC_Halt is an instance of MC_halt function block
HaltComplete := Inst_MC_Halt.Done;              //store Done output into user defined variable