MC_Stop_BkPlcMc (from V3.0)
The function block cancels a current axis motion and monitors the stop operation.
 | The stop operation initiated by this function block cannot be interrupted by other function blocks. A function block MC_Halt_BkPlcMc should be used to enable an axis restart during a stop operation. |
Inputs
VAR_INPUT
Execute: BOOL;
Deceleration: LREAL; (ab/from V3.0.5)
Jerk: LREAL; (ab/from V3.0.5)
RampTime: LREAL; (ab/from V3.0.5)
BufferMode: MC_BufferMode_BkPlcMc:=Aborting_BkPlcMc; (ab/from V3.0.8)
END_VAR
Name | Type | Description |
|---|---|---|
Execute | BOOL | A rising edge at this input ends a movement being carried out by the axis. |
Deceleration | LREAL | [mm/s2] The deceleration to be applied. |
Jerk | LREAL | [mm/s3] The jerk to be applied. |
RampTime | LREAL | [s] The required stopping time. |
BufferMode | MC_BufferMode_BkPlcMc | reserved. This input is provided in preparation for a future build. It should currently either not be assigned or assigned the constant Aborting_BkPlcMc. (from V3.0.8) |
Inputs/outputs
VAR_INOUT
Axis: Axis_Ref_BkPlcMc;
END_VAR
Name | Type | Description |
|---|---|---|
Axis | Axis_Ref_BkPlcMc | Here, the address of a variable of type Axis_Ref_BkPlcMc should be transferred. |
Outputs
VAR_OUTPUT
Busy: BOOL;
Done: BOOL;
Error: BOOL;
ErrorID: UDINT;
Active: BOOL;
CommandAborted: BOOL;
END_VAR
Name | Type | Description |
|---|---|---|
Busy | BOOL | Indicates that a command is being processed. |
Done | BOOL | This indicates successful processing of the operation. |
Error | BOOL | The occurrence of an error is indicated here. |
ErrorID | UDINT | An encoded indication of the cause of the error is provided here. |
Active | BOOL | Indicates that a command is being processed. |
CommandAborted | BOOL | Indicates that processing of this command was aborted by another command. |
Behavior of the function block
On a rising edge at Execute the function block checks the transferred axis interface. A number of problems can be detected and reported during this process:
- The stop can only be executed if the axis is actively carrying out a movement. If it is stationary, the function block immediately asserts the Done signal.
- If the axis is already in an error state, or if it is in the process of carrying out a stop operation, it responds with Error and ErrorID:=dwTcHydErrCdNotReady.
- If the axis is in a state, in which it is controlled by a coupling with another axis or a comparable mechanism, it responds with Error and ErrorID:=dwTcHydErrCdNotReady.
The Stop operation begins if these checks can be carried out without problems. Deceleration is used, if this parameter is recognizably greater than 0. Otherwise RampTime is used to calculate a deceleration, taking into account the reference velocity. If a jerk-limiting control value generator is selected, Jerk is used if this parameter is recognizably greater than 0. If none of the mentioned parameters is recognizably greater than 0, the axis parameter MaxDec and MaxJerk are used.
The next reachable position is determined and used as new target position, taken into account the current set velocity and the currently valid parameters. Once this position has been reached, the axis assumes its regular behavior in idle state.
| The RampTime specifies the time during which the axis is to be decelerated from its reference speed to standstill. If the axis moves with a different velocity, the braking time reduces accordingly. If control value generators with creep mode are used, the corresponding time is added to the braking time. |
If the motion algorithm reports an error code while the movement is being executed, the system responds with Error and ErrorID:=the motion algorithm's error code. If the complete processing is prevented by the activity of another function block, the system responds with CommandAborted. Successful completion of the operation is reported with Done.
A falling edge at Execute clears all the pending output signals. If Execute is set to FALSE while the operation is still active, the initiated stop continues unaffected. The signals provided at the end of the movement (Error, ErrorID, Done) are made available for one cycle.
| The output Active is currently identical to the output Busy. |