Dear,

 We are using Mc_moveabsolute block for position control but facing some problem regarding setpoint velocity. we are set setpoint velocity 100 mm/s after block execution new setpoint velocity 50 mm/s not effected. So please suggest me how to implement new setpoint velocity after Mc_moveabsolute block execute for position control.

You have to send a new motion control command to the axis, with the same target position and the new speed. To do this, a new rising edge at the EXECUTE is required.

You may "reuse" the "old" FB/instance or use a "new" one.

The "old" MC_MoveAbsolute will show "CommandAborded" to indicate it was "replaced" before the movement (started with this motion control command) was finished.

AutoGen_333109

Dear,

 We are using Mc_moveabsolute block for position control but facing some problem regarding setpoint velocity. we are set setpoint velocity 100 mm/s after block execution new setpoint velocity 50 mm/s not effected. So please suggest me how to implement new setpoint velocity after Mc_moveabsolute block execute for position control.

You can use Override.Velocity parameter to change the actual speed of the motion command being executed. 

My Mc_MoveAbsolute block has not contain ‘Override’ input, but I resolved a problem: Set impulse on ‘Exucute’ with Velocity1 and some ‘TargetPosition’, check when CurrentPosition  becomes greater (or lesser) than Position_to_slow_down, sent to block Velocity2 and after sent TRUE to ‘Execute’ input.

AutoGen_6254902

My Mc_MoveAbsolute block has not contain ‘Override’ input, but I resolved a problem: Set impulse on ‘Exucute’ with Velocity1 and some ‘TargetPosition’, check when CurrentPosition  becomes greater (or lesser) than Position_to_slow_down, sent to block Velocity2 and after sent TRUE to ‘Execute’ input.

Or you can use the following idea to retrigger the motion:

region absolute-move      
     if (#statAbsolute.isBusy = FALSE)
     then // No retrigger required
        ;
     elsif (#instMoveAbsolute.Position <> #statAbsolute.position)
        or (#instMoveAbsolute.Velocity <> #statAbsolute.speed)
     then // Retrigger needed: setpoint has changed
        #instMoveAbsolute(Axis := #Axis,
                          Execute := false);
     end_if;
     
     #instMoveAbsolute(Axis := #Axis,
                       Execute := #statAbsolute.execute,
                       Position := #statAbsolute.position,
                       Velocity := #statAbsolute.speed,
                       Done => #statAbsolute.isDone,
                       Busy => #statAbsolute.isBusy,
                       CommandAborted => #statAbsolute.isAbort,
                       Error => #statAbsolute.isError);
  end_region absolute-move

I think you misunderstood the override parameter.
This is not a parameter at the instruction, but it is a paramter in the technological object's data block. You can just use this for exactly the purpose you are looking for. Just trigger the move command, and if you want another velocity, then use the override parameter in the DB of the TO and adjust its value, that's all.

Regards,
daviso

daviso

I think you misunderstood the override parameter.
</snip>

Unfortunately @AutoGen did not mention which controller is used. The version of the motion control blocks is also unknown. There may simply not be an override option.

My answer does work for the S7-1200 (FW:V4.2) within Step7 V15. 

@qwazee: You're right, I was thinking of S7-1500 motion control. People should mention the equipement they're working with when asking questions…